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psrcBOiaciCAi. xeview fubucations
Psychological Monographs
EDITED BY
JAMES R. ANGELL, UNivERsrry or Chicago
HOWARD C. WARREN, PuncetSn Univmsity [Indexi
JOHN B. WATSON, Johns Hopkins Univebsity (Xerinr) A^^>
ARTHUR H. PIERCE. Shtth College (BfOtUn)
Volume XII
1909-11
FUBUSHED BV
THE REVIEW PUBLISHING COMPANY
41 NORTH QUEEN ST.. LANCASTER, PA.
AM> BALTIMORE, MD.
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155734
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CONTENTS
Three Studies from the Psychological Laboratory of the
University of Chicago:
1. A Study of Sensory Control in the Rat. Florence Rich-
ardson. Pp. 124.
2. On the Influence of Complexity and Dissimilarity on
Memory. Harvey A. Peterson. Pp. 68.
3. Studies in Melody. W. Van Dyke Bingham. Pp. vi+88.
4. Report of the Committee of the American Psychological
Association on the Teaching of Psychology . Pp. 93.
5. Mental Life of the Rhesus Monkey. William T. Shep-
herd. Pp. 62.
The Monographs in this volume are Nos. 48-52.
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Psychological Monographs
Val. Xn October, 1*M
Na. I Wbolc Ne. 4S
Psychological Review
BDITSD BY
J. MARE BALDWIN
HOWARD C. WARREN JOHN B. WATSON
PlIHCKTDN UmVUtlTT JoHHI HoTKlNI DMITUItlTT
JAMES R. ANGELL, UmriRUTi or Cbkaoo (£Jmr */ ikt PijckJtpcal MmtT'fl'')
A Study of Sensory Control in the Rat
Florence Richardson, Ph.D.
Associate Professor of Psychology, Drake University
Studies from the Psychological Laboratory of the
University of Chicago
THE REVIEW PUBLISHING COMPANY
41 NORTH QUEEN ST., LANCASTER, PA.
AND BALTIMORE, MD.
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I desire to express here my obligation to Professor James
R. Angell for constant assistance and encouragement. I am
particularly indebted to Professor John B. Watson, under
whose immediate direction the experimental work here pre-
sented was undertaken and carried out. My thanks are due
also to Professor Harvey Carr for su^estions and criticisms
of the manuscript, and to Miss Ethel Chamberlain, who assisted
me during a portion of the experimentation.
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Introduction.
«. Probleni and Scope of Preaent Study i
h. General Method 3
PART FIRST.
I. EXPUDIENTAL RbSULT*.
^. TeMf on Problem Box t 7
1. DcKiiption of Appantui and of the I^eirning Procew 7
2. Statement of ReatUti: 10
a. On Normal White Ran 10
t. Or Noimal Black-and-White Rati I j
c On Blind Ran 15
J. On Anoamic Rati 17
3. Summarr 21
B. Temon PtoUem Box II 26
I. OeKription of Apparatu* and of the Learning Process 26
1. Statement of Resuht: 29
a. On Normal White Rats 29
i. On Normal Black-and-White Ratt 32
t. On Blind Ratt 34
J. On Anoimic Rati 34
3. Effect on Rat* of Changing Poiition of Plane 90° to Ri^l 38
4. Summary 41
C. Te«tf on Problem Box III 46
1. Defcripdon of Apparatus and of the Learning ProceM 46
2. Statement of Results: 47
*. On Normal White Rat* +7
h. On Normal Black-and-White Rat* 49
t. On Blind Rat* 50
J. On Anosroic Rat* 52
3. Effect on Rat* of Changing Position of Box and Cage 52
4. Summary jS
D. DiKuttion of Curve* ihowing Average Time-records of Normal and of
Defective Rat* in Learning the Maze 60
£. General Conclusion* Based upon Results of aboveTests 61
F. Problem IV 69
1. Description of Apparatus and of Method of Teaching Rats to
Jump 69
2. Jumping in Constant Direction, i.e.. Apparatus in East-West Posi-
tion 76
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i» CONTENTS
i. Statement of Results 76
a. On Normal White Rats 76
b. On Normal Black-and-White Rats 76
e. On Blind Rats 79
i. On Anofmic Rat 83
II. Summary 85
3. Effect of Chan^ng Direction in which Jump Must be Made 85
I. Statement of Refultt 88
a. On Normal White Rats 88
h. On Normal Blaclc-and-White Rats 90
e. On Anosmtc Rat 92
iV. Summary 92
4. Effect of Altering Distances between Platfoims 93
a. Effect of Altering Horizontal Distance 93
f . Statement of Results 94
«. On Normal White and on Normal Blaclcand-Whitc
Rats 94
h. Effect of Altering both Horizontal and Vertical Distancet. . 95
(. Statement of Results 96
«. On Nomal White and on Normal Black-and-White
Rats 96
II. Summary 97
5. Conclusion 98
PART SECOND.
A. Effect of Training upon the Rats 103
I. Experimental Results 103
I. Comparison of Records of Trained and of Untrained Rats 103
a. Normal White Rats on Problem 1 103
b. Blind Anosmic Rat on Problem 1 106
c. Normal White Rats on Problem III 107
d. Normal Black-and-White Rats on Problem III 108
e. Blind Rats on Problem III 112
1. Summary of Facts 114
II. Conclusions 114
B. Individual and Sex Differences as Shown by Behavior 117
1. Sex Differences I17
2. Individual Differences 119
PART THIRD
General Conclusions 123
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INTRODUCTION.
a. Problem and Scope of Present Study.
The work presented here grew out of a series of tests
upon the rat, begun in April, 1906. Watson,* in an investiga-
tion which he was carrying on at the time, had found that the
only necessary sensory avenues employed by the rat, in learning
the maze, were the kinaesthetic and oi^anic, and that visual,
olfactory, auditory and tactual impressions could in all prob-
ability be dispensed with.
The present problem parallels that of the above investigation
and may be briefly stated as an attempt to determine the func-
tion of the different sense organs in the reactions of the rat
K> situations requiring various types of movement. In prob-
lems like that of the maze, the general activity of running is
the one most utilized. The sensori-motor arcs need only to be
integrated : Whereas the coordinations which are employed in
the learning of such problems' as Nos. I, II, and III of the
present series (such as digging, bending the back and climb-
ing upward through holes; stepping on a plane and advancing
upon it until a trap door falls; raising the head and lifting a
latch with the snout, etc.) are not so habitual to the an[mal.
The sensori-motor arcs involved in the learning of these prob-
lems must be established more or less de novo, and at the same
time be combined into a series which can function more orless
auK)matically.
It may be assumed that since running, which is the chief
form of activity involved in the maze, is so reflex-like in char-
acter, it might well be carried out by the use of kinesthetic
sensory impressions alone. The coordination involved m prob-
lems of the manipulation type, not being so reflex in character,
would, if the factors involved in the formation of human habits
' Watton, J. B., Psych. Rev., Mor. Supp., vol. viii, 110. 2, 1907.
'These problem bones are described in detail further on.
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FLORENCE RICHARDSON.
may by analogy be assumed to hold in the case of the rat,
require the cooperation, at first (i. f., at least during the learn-
ing process), of visual and olfactory impulses, provided such
were at hand. Later on such coordinations might in their
turn be controlled by kinesthetic means.
I The general type of coordination in the maze, is, as has
been stated, that of running. The animal, in addition, must
learn what turns to make, and where to make them. Carr
and Watson's ' later report of work witii a maze in which the
length of the alleys may be changed, goes to show that the
knowledge of the direction of the turns and the point at which
they occur, is governed by the kinaesthedc and organic char-
acter of the cues for the turns. This fact explains the success
of blind and anosmic rats in learning the pathway in a maze.
In Problem I of the present series, the pathway which the
animal must follow is more complex than that of a maze in
that it involves climbing down from the top of a box, finding
a hidden entrance to the food box, digging away an obstruc-
tion, crawling under a board and up through an opening.
The solution, however, is more simple than that of any of the
others in that it demands Httle manipulation, and on the whole
approaches the labyrinth type of problem. How much the
guidance from vision and olfaction may assist the functionings
of kinesthetic and organic processes in the learning of this
type of problem is one of the chief questions to be answered
by the present research.
Problem II is diought to be still more difficult for the rat.
The animal must learn here to press down an inclined plane
at a distance from the box, and establish the association of
the falling of the plane with the opening of the door of the food
box. It is possible that olfaction might render the food stimu-
lus more intense, and thereby quicken the reactions of the
animal; but the question we are more concerned with is
whether the olfactory values of the different parts of the envi-
ronment, such as the smell of the plane, of the door of the
food box, etc., aid the animal in adjusting to such situations.
' Jour. Comp. Neur, and Psych., vol. xviii, no. I, 1908, p. lyW.
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A STUOr OF SENSORr CONTROL IN THE RAT. 3
Vision might also be the means by which he attains his orien-
tation in such an open space as surrounds the apparatus.
In Problem III, the rat must raise a latch holding a door
in place in order to reach the food. The area in which the
successful movement must be performed is vety circumscribed,
being only the immediate locaU^ of the free end of the latch.
Vision may be necessary ta locate the door and the latch.
Olfaction may possibly play a considerable role here likewise.
Problem IV necessitates the rat's jumping from one plat-
form tt) another in order to obtain food. It is hardly con-
ceivable that this coordination could be successfully executed
for any considerable distance without the aid of vision.
If different ^pes of sensory control are used by the animal
in meeting such different situations, the fact should become
evident in a comparison of the behavior of normal rats with
that of rats deprived of die use of the important sense organs.
In carrying out this investigation groups of normal white
rats, normal black-and-white rats, blind rats and anosmic
rats' were used.
During the course of the above research the experimenter
collected data bearing upon the questions of sex and individual
differences, and on the possible influence of previous training.
While these topics were subsidiary to the main problem, the
results seem of sufficient value to justify their presentation.
b. General Method.
The experiments which are here reported were as carefully
controlled as possible : the tests were made every day and at the
same hour of the day. Unless otherwise specified, the rats
were about 120 days old when the experimentation began.
This standard of age was adhered to because the rats at this
time have much of the energy of youth together with fully
developed neural and physiological mechanisms. Fidelity to
this requirement, as m: ' '
' The anosmic rats, with 1
lion which afflicted die tat 1:
its woric. On this account, 1
oTdefective rats is not as con
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4 FLORENCE RICHARDSON.
much difficulty. A need for a group often arose when none
in the laboratory satisfied the demands. This frequently
meant a considerable delay until a litter of the proper age could
be found. As a rule, the rats had been bred in the laboratory
and were known to be of good stock. Males and females
used in the work were kept in separate cages and, for the most
part, were tested on separate apparatus. This was done as
a check K> any possible tendency toward tracking, and to
minimize the emotional disturbance of fear caused by an
unusual odor. The problem boxes were carefully washed and
left for a time in the open air before being assigned u> a new
group. On account of the fact that the rats were required
to get into the problem box for food, rather than K> release
themselves from confinement, it was necessary to inclose the
area in which they were to work. A larger cage of wire netting
was placed over the problem box, which is spoken of in later
descriptions as the control cage. When an animal is confined
within his problem box, no such outer cage is necessary. But
unless a rat were — in a measure — confined, his insatiable curi-
osity would preclude a solution of his problem within reason-
able time limits.
The boxes were kept covered by these cages when not in
use so that no predatory wild rats could leave an odor on them.
On one occasion the laboratory boy carelessly removed the
control cage, and left a problem box exposed. Wild rats had
evidently been about, for the next day each rat introduced into
the cage became exceedingly timid with fright, and the emo-
tional reaction was so strong and so persistent that it necessi-
tated the abandonment of the series. Upon another occasion,
when the rats which had just finished their work for the day
were eating in the problem box, the experimenter killed several
wild rats which had been caught in a trap. Every effort was
made to remove any trace of odor from the experimenter's
hands; but when the white rats were carried back to their
living cages one of them seemed much frightened. The next
day he objected to being handled and when put into the test
cage he crouched. When he moved about at all, he slunk
along close to the floor, cringing, and became quite motionless
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A STVDT or SENSORr CONTROL IN THE RAT. $
at any loud or sharp sound. For several days his behavior
su^ested fear, and only after the fifth day had passed did he
revert to his normal behavior. Possibly it is not necessary to
go so into detail in these matters. But those who have worked
with animals realize how difficult it is to maintain constant
conditions. If the experimenter takes the precaution to sute
explicitly the methods of control in the work reported, it inspires
more confidence in the minds of those who wish to utilize the
results.
Milk-soaked bread, except where otherwise stated, was the
food stimulus used. Hunger was relied upon as being the
most constant and most natural incentive to activity. The
rats were allowed to eat but sparingly of the food after the
first successful efforts, but after the last trial for the day had
been given they were permitted to satisfy their hunger. On
the whole the method of reward was adopted as the most
efficient means of controlhng the reactions of these animals.
The rats were never allowed to become ravenously hungry.
Such a condition puts a premium upon useless and frantic
movements.
The food in the problem box was always placed in the same
location. The position of the food box in relation to the con-
trol cage, and of both to the points of the compass, was con-
stant. The rat was always put into the cage at the same point
and with approximately the same bodily orientation. As the
entrance was at the east in the first three problems, the rat
entered the control cage facing west. Particular precaution
was taken in this matter, since all experiments with the rat
have shown him to be very susceptible to slight changes in his
environment. He has a tendency to establish a pathway from
the entrance to the food box, and to follow it carefully. Unless
he attains orientation quickly and pursues this pathway he
becomes confused. This confusion is evidenced by the display
of the same random activity present in his first trial.
Since the time records must furnish the greater part of the
basis of comparison in these problems especial care was taken
to maintain constant conditions. Comparisons were to be made
between entire groups, and between individuals of thesame or
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6 FLORENCE RICHARDSON.
different groups. This fact, likewise, necessitated the employ-
ment of great vigilance in experimentation.
The animals were always tame when beginning the work
and were accustomed to being handled. Every group was
given the different tests in the same serial order. On account
of the possible influence of education, groups were not set upon
die second problem without the experience of the first, '^ilc
at the time the difi^erence between the work of trained and of
untrained rats was only hypothetical, die results reported here
(p. 103) seem to justify die precaution.
Care in maintaining these conditions — such as die age of
die rat; amount of previous training; continuous daily experi-
mentation; and an equal number of daily trials — made the
work difficult. It is admitted that even with the care takeni
the conditions were not ideal. In many cases a comparison
is made of tables and curves formulated from the records of
groups composed of unequal numbers of individuals, and of
unequal sex representation. However, the writer, at least, feels
that the records obtained represent very fairly the abilities of
the animals experimented upon. While much in the way of
accidental variadon is doubdess present, the records on the
whole are reliable.
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PART I
I. Experimental Results.
A. TESTS ON PROBLEM BOX I.
/. Description of Apparatus and General Statement of Learn-
ing Process.
TTw first problem box used was a modified form of the one
used by Small' and by Watson.'
In tjiis box the rat has to dig through sawdust in order to
reach the entrance of the food box. The box is 30 cm. long,
22-5 cm. wide and 17.5 cm. high, the top and the bottom being
of inch boards. The box is raised by supports at the comers
so that the bottom is 5 cm. above the table upon which the
box rests. The sides and ends of the box are covered with
wire netting. The netting on the sides extends down to the
table* while that on the ends goes only to the bottom of die
box, leaxing an open alley under the box between the two
extended side walls. In the center of the raised Boor is a
rectangular opening through which the rat climbs from below
into the box to obtain food. This opening is 8 cm. by 10 cm.
A larger opening in the top of the box, 10 cm. by 12.5 cm.,
allows the experimenter both to admit the food and to remove
the animal from the box (see fig. I). This opening has a thin
board cover which is pivoted on a screw near one of its ends.
During experimentation the sides and ends of the box were
covered with sawdust to the height of the floor of the box.
This height was chosen arbitrarily to insure a practically con-
stant amount of sawdust for the animal to remove. A wire
netting control cage, 52.5 cm. long, 37.5 cm. high and 37.5 cm,
wide, with a door on one side, was placed over the box.
> Am. Jour. Piych., vol. xi., no. 2, p. 135.
* Anim^ EJueatioa, p. 14.
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8 FLORSNCE RICHAKDSON.
The problem with which the rat is confronted is the necessity
for removing the sawdust either at the north end or at the
south end of the box. Since the east and west sides are entirely-
covered with wire netting, movements at these points are use-
less. The rat must dig away a quantity of sawdust, crouch
and then crawl under the floor of the food box proper, and
later climb up through the hole in the floor. At the b^inning
of the test the animal was always placed on the top of the box
facing west. It must learn to descend to the floor of the cage,
orient itself as regards the north or south end of the box,
and dig underneath the floor of the food box as described
above. As has been stated, the pathway which the animal
Fig. ..
must establish is relatively simple, and, with the exception of
the digging, crouching and cHmbing movements, the problem
approaches in its simplicity that of the labyrinth type.
The above task was presented first to normal, then to defec-
tive rats in the hope of obtaining evidence for the type of sen-
sory control utilized by the rat in forming such an association.
The normal rats furnished the standard time and error record
with which the records of the defective animals were compared.
The rats at work upon this problem were fed once a day
for three days in the box, a handful of sawdust having pre-
viously been sprinkled over the floor to accustom them to its
presence.
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A STVDT OF SENSORT CONTROL IN THE KAT. 9
The time consumed during the test was taken by means of
an ordinary stop-watch, which was started just after the door
of the cage was closed after admitting the animal, and was
stopped when the rat had all four feet in the food box.
The general description of the learning processes involved
in this problem may be easily set forth by a reference to the
following notes of an individual taken at random from the
records of the normal rats.
Notti on tbt Behavior of Normai Ftmale Rat If ia learning Prohltm I.
TOIAL.
4/M/06
Examined moit carefully both outer cage and food box.
Seemed loget odor of food and dug two-thirds length
of east side. Scratched li^tly at west: active but
unfortunate. Began scratching at south, but gave
up immediately and began at east. Dug under at
west end of north side. Did not enter food box at
once. Time 17.65 min.
2
Entered at weffi of north, with few useless movements.
Time .25 min.
3
Entered at west of north. Time. 15 min.
4/11/06
4
Scratched on east side, left, returned again to east and
dug frantically, then entered from south- Time 1 .02
5
Scratched at east, entered at south. Time .15 min.
6
Hesitated for an instant at east, but did nat scratch.
Time .08 min.
4/11/06
7
Time .18 min.
8
Entered at nonh; dug spasmodically. Time .42 min.
South. Time .17 min.
4/13/06
10
South. Time .12 min.
Went to south, hesitated, seemed confused, dashed to
north and in. Time ,20 min.
North. Time .03 min.
The above notes show many characteristic features of the
learning process. The quick drop from high to low time record,
which may be seen from the form of the curve, (Plate I ) is typical
of the first and second trials. The sudden elimination of
useless movements is not always so pronounced as in the case
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10 FLORENCE RICHARDSON.
noted above. Often errors persist through half of the
series. The manner of the elimination of errors is well illus-
trated in the above notes. There is at first a persevering effort
to dig through at the east or west side, followed by less and
less persistent endeavor at these places; later there is present
only a hesitancy in passing such points, and finally, as the habit
progresses, no notice of them at all.
This procedure quitt parallels that of the rat iA eliminating
his errors in the maze. He at first explores the cul-de-sac
with care, then runs into it for shorter and shorter distances,
hesitates at its opening, and finally disregards it utterly. Such
behavior is indicative of the early random and accidental
nature of the movements, and illustrates one phase of the kin-
xsthedc character of control.
2. Statement of Results.
o. On Normal White Rats.
In order to obtain normal records with which to compare
the records of defective animals, a group of eight white rats
was used. These rats were I22 days old, all of one litter
and were healthy, active individuals. Being bred in the labo-
ratory their previous ancestral history was known to be of
the best. Four of them were males and four were females.
None had been used previously in experimentation. Table I
shows die average records of this group. On Plate I the
graphic representation of this average is given.
The table shows also the maximum and the minimum time
records for each trial, the number of rats whose records coin-
cide with the average for the group at that trial, and the number
whose records are greater, and the number whose records are
less than the average. Since average alone is not always an
adequate representation of the accomplishments of a group,
these few supplementary facts are added to make the average
of greater value.
When the recordswere tabulated, the rat making the maximal
and the animal making the minimal record at each trial was
noted. The number of maximal and of minimal records made
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A sTVDr or sENsosr control in the rat. 1 1
Table I.
Sbmmng ibe aotragt, ibt mtmimum, and the maximmm timt-rttorJt of tight
normal v/bitt rait mf«» PrMtm I. Tbt last ibnt niumnt tbaw tbt HUttwtr
of animals vtboie timt rtcords are (/) tifual (o tbt avtragt, (ji) Mow and (j)
atave the aoeragr.
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FLORENCE SICBAKDSON.
Table I. — Conanued.
TTtlAL, *"
lACE. MIN
miu. UAXn
iUH.
■•
2.
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39
09
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I
4
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V
46
06
03
5
47
06
03
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6
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oi
03
4
49
03
10
4
S"
■3
08 1
26
7
'
by each individual was then given its percentage value. These
percentages are shown below.
Minimal RecorJt.
Maximal Recordt.
Male 1 41.6 Male I
Male II 10.6 Male II 8
Male III 22 .0 Male III 7
MalelV 10.6 Male IV i+
Female 1 1 Female I...
Female II 6 Female II...
Female III 3 Female III . . .
Female IV 5 Female IV. .
29
These supplementary tables with others similar In character
will be discussed in a later section (p. 117). They are inserted
here to show, in a measure, how dependent the average may
be upon the variations among individuals. Male IV and
Female I are responsible for more than one-half of the longest
r. cords. Male I, on the other hand, though he has not the
least percentage of maximal records, has made more than two-
fifths of the total number of minimal records. In other words,
Digilizcd by Google
2. 3-
3 '
3 •
2 1
2 2
3 '
3 '
3
five were
als were
'on.
of the
itation
tight
Digilizcd by Google
14 FLORENCE RICHARDSON.
Table II.
SbouiiHg the average, tbt minimum, and the maximum time-records af four black-
and-white females upon Problem I. The last three coiumnt ihoio the number
of animali whose lime-recordt are (j) (juo/ to the average, (2} below, and
(j) oiov/ ibr average.
MO or
™«i. -"•
2ACE. wur
■HUM. UAXI
HUM.
'■
3
;..
«. m,
I
82
V '
53
a
23
'7
37
3
«
67
S»
+
12
07
■7
5
7»
05
6
■7
06
47
7
08
07
08
OS
■9
9
>3
OS
22
08
06
10
11
07
05
10
u
06
OS
06
'3
07
OS
10
14
18
OS
53
'S
06
OS
09
16
07
OS
10
■7
10
07
■4
18
II
07
26
■9
05
OS
06
20
09
04
■7
21
OS
03
07
21
OS
04
07
'3
04
03
OS
2+
OS
03
08
»S
OS
03
06
26
06
03
12
'7
II
03
3S
28
04
03
04
29
04
03
04
30
03
03
04
31
OS
03
10
3'
04
04
04
33
04
03
04
34
04
03
06
35
04
04
OS
36
05
03
07
37
06
03
12
38
07
04
09
DiBiiizcdb, Google
A STVOr OF SENSORY CONTROL IN THE RAT.
Table II. — Continued.
HACB. MIN
MUM. MAXI
MUM.
*■
1.
3-
39
04
03
0?
40
04
11
4'
03
02
04
41
04
ID
43
08
03
>7
44
61
*s
06
OS
07
♦6
04
03
OS
+7
04
03
OS
48
04
04
04
49
04
03
OS
SO
03
03
04
c. On Blind Rats.
Nine blind rats of which four were males, and five were
females, were trained on the problem.' The animals were
about four months old and all were in excellent condition.
Table III gives the records made by eight animals of the
group. A curve on Plate I shows the graphic representation
of the averages given in this Table.'
Table III.
Sbavnng the average, the rRinimsm anJ the maximum Ume-rtnrdl 0/ eight
tliaJ rait upau Problem I. The last three eolumns sham the numker of
animdt whott records art (/) equa! to the average, (2) belovi, and (j)
above the mierage.
TRIAL.
AVERAGE.
MINIMUM.
MAXIMUM.
'■
X
3
1
mill.
a73
m,j
6.4";
3
1
■5>
■as
1.00
3
3
■9'
■n
"■97
4
4
■73
.'7
1-45
2
S
i.S»
1.20
8.06
I
I
•S'
.10
1.42
3
' Cf. WatKHi, iV,d, pp. +7 ff.
'The time-records of one male are not included in the average. They a
unusually slow and are discussed in the paragraphs on individual differences.
Digilizcd by Google
FLORENCE UCBARDSON.
Table III- — Continued.
NO. or
TOIAt *"
RACE. KIN
MUM. MAX
MUM.
'•
2.
3-
7
'3
12
42
1 ' ,
S
49
07 1
93
9
70
04 I
92
1 S
lo
SO
■7 ■
'3
1 4
II
84
07 3
60
u
35
06
63
'3
28
07
67
I*
49
■3 '
'3
'S
18
05
S3
i6
■9
OS
48
5
•7
17
04
42
i8 I
06
OS 6
13
■9
30
OS
83
20
21
OS
52
II
45
05 I
aa
24
05
«3
■3
42
04 I
OS
14
"3
OS
33
25
12
05
23
26
37
07 1
=7
18
09
32
4
28
15
OS
3a
29
57
07 3
'3
30
3<
07
45
3"
'5
08
52
32
18
OS
42
33
■S
08
'5
34
'7
07
75
35
•3
04
30
36
16
OS
47
37
13
07
78
38
20
06
42
39
26
37
»7
40
26
05
70
41
16
05
38
42
26
04 I
6
43
34
OS I
33
6
44
11
od
45
5
45
25
07
9*
S
4<i
22
47
53
6
47
18
06
49
6
48
2t
07
42
5
49
'!
04
83
5
50
13
04
45
6
DiBiiizcdb, Google
A STUDY OF SBNSOSr CONTROL Iff THE RAT. 17
The averages in the above table are low, but lack uniformity.
There was wide variation among the individuals of the group,
which was noticeable not only in their time records, but in
their general behavior.
The following table shows the number of minimal and of
maximal time-records made by each blind rat.
Minimi. Maximal.
Male II 23 Male II +
Male III 21 Male III 6
Male IV 6 Male IV 3
Female I i Female 1 46
Female II 22 Female II 8
Female III 22 Female III 4
Female IV 2 Female IV 25
Female V 3 Female V 4
Female IV made one-fourth, and Female I nearly one-half
of the total number of maximal records. Males II and III
and Females II and III, leather made 88 per cent of the
minimal records.
J. On Anosmic Rats.
Since in these problems the animals at all times are in rela-
tively close proximity to the food so that odor stimuli might
affect their reactions, five anosmic males were tested upon
the problem. Each had had the olfactory bulbs removed as
described in detail by Watson.' The animals were in good
condition when experimentation was begun — forty days after
the loss of the bulbs — and remained so throughout the test.
Table IV gives the time-records. The graphical representa-
tion made from the average is shown in Plate I.
It seems unnecessary to comment at length on the results
given in the table and curve. The effect of individual varia-
' IbiJ. p. 49 W.
Digilizcd by Google
l8 FLORENCE RICHARDSON.
Table IV.
Shouiing the avrragf, tbt minimum and iht maximum limt-rtcords of jive anoi-
mtc mtdtf upon Problem I. The last three ctJumnt sboui the number of
animalj whose records are (/) ei^uid to the average, (z) below, and (5) d&MW
the overage.
NO. OF
TRIAL. *''E»'
sat. MiN
MUM. MAXI
ilUM.
'■
2.
3-
" '3
27 I
62 +6
30
2
63
25 I
98
3
22
13
40
4
3»
14
52
S
28
07
6z
6
43
07 2
92
7
26
07
50
2
8
57
9
32
07
73
10
14
07
n
07
43
12
3"
07
98
"3
30
07
90
14
20
06
37
"S
31
06
67
2
16
36
!l
63
i
•7
22
06
40
18
28
16
50
19
20
07
43
20
24
08
47
21
r6
03
25
Zl
32
05
78
23
35
07 1
OS
24
Zl
OS
42
15
■♦ i
08
22
16
^3
06
42
27
20 1
07
37
28
30
07
67
19
27
06
62
30
16
13
24
3'
07
42
3»
27
OS
♦8
33
29
OS
82
34
17
06
33
35
28
07
70
36
57
04 1
60
.^7
39 !
OS ■
18
38
17 .
04
32
*
DiBiiizcdb, Google
A STUOr OF SENSOSr CONTROL IN THE RAT.
Table IV- — Conrinued.
NO or
TT.IAL *"'^
%GE. WIN
UUU. HAXn
HUlt.
•■
^■
3-
39
3»
08
6,
3
40
28
08
SI
4'
17
07
18
♦2
29
ss
♦3
»3
4a
I
+t
40
28
b7
45
08
1«
46
3S
08
7S
+2
as
OS
68
2
48
29
05
Ql
I
49
24
09
41
2
W
4'
07 I
'3
•
tions on the curve is roughly shown in the table below, which
gives the percentage of minimal and of maximal records made
by each rat.
Minimal.
ptTcint.
Male I' o
Male II 6
Malelll 38
Male.IV 56
Male V o
Maximal.
Male 1' 55
Male II 10
Male!!! 6
Male IV 2
Male V 27
Male I, as is indicated, made more thanone-half of the longest
time-records: the time-records of Male V were also long.
Were it not for the eccentricities of these two rats, the curve
' The emotional attitude of Male I, together with a tendency to gnaw at all
that came in his way was responsible for his apparent slowness. He was a v«y
active and hardy rat, but his effbiti were entirely roisdirected. He spent much
of his time endeavoring to clamber from the top of the box, and once down, was
morethanlikdytoclimb back up immediately and b^n all over again hii frantic
attempts to get off. When he did spend any length of time on the floor of the
cage, he vented his energy in 'gnawing at the outer cage, or at the wire netting
of the food box. On later problems his propensity to gnaw became the despair
ofthe experimenter, as it necessitated perpetual repairingof the apparatus. Rat
V likewise spent much time in the endeavor to get off the box. He finally
acquired the habit of getting off at a point nearest the door. Later, if he did
not at once reach this position, he seemed utterly at a loss what to do.
Digilizcd by Google
FLUBENCE SlCBdSDSON.
DigilizcdbyGOO^Ie
A STVDY OF SENSOSr CONTROL IN TBE RAT. 21
for this group would have been considerably lower than it is.
The records of Male IV were exceptionally short.
J. Summary.
a. Average Time-records for the Total Series of Fifty Trials.
In attempting to summarize the results of tests with different
groups of rats upon this problem, only a comparison of the
records made by the normal and the defective animals will be
given here. The discussion of the records and a theoretical
interpretation of them together with the facts brought out in
lattr summaries will be given in the final conclusions at the
end of Part I (p. 6i).
Tlie sum of the separate time-records for the entire series
of fifty trials given each rat was obtained, and it was then
divided by the total number of trials given that animal. This
gave an average time-record for each animal on the problem
and aiforded one basis for the comparison of records of indi-
viduals. From the individual averages obtained as above
described a group average was made which serves as an addi-
tional means of comparing the records of groups of normal
rats with those of the groups of defective animals.
TABLE IHOWINO GROUP AVBRAGB OF THE TOTAL TIME (50 TEIAU) CON8UHBD
BY MORMAl AND BY DErECTIVB RATS IN LEARNING PROBLEU.
Average Records of Groupi.
Bhck-and-Whiw 09 Blind . . . .
White 3+ Anosmie .
Averager of Ricorit of Individuah in the Grouft.
BLACK-AMD-WBtTS.
w,m.
BUND.
ANOSMIC.
Fonak I
.10
Male I
7
Female I
II
Male I
-n,«.
Female II
,o«
Male II
■W
Female 11
42
Male 11
2S
Female III
■°9
Male III
■ iR
Female III
24
Male III
.oq
Female IV
(iH
Male IV
Female IV
Male IV
Female V
■?1
Male V
.60
Female I
Male I
Female II
,20
Male II
Female III
■ 17
Male III
Female IV
-46
Male IV
17
DB.zcdb, Google
22 FLORENCE RICHARDSON.
As may be noted in the above table the average of the group
of black-and-white rats is phenomenally low as compared with
that of the other groups. The individual averages of this
group are very uniform. The highest individual average,
which is .10 min., is just one-half of the lowest average made
by any one normal white rat, viz., .20 min. The group aver-
age of the blind rats is high, but the high variations
among individuals are in part responsible for the high group
average. Five individual averages among the blind are lower
than the group average of the normal white rats, and the lowest
average of a blind rat, .24 min., is but little above that of
the lowest individual of the normal white rats, .20 min. The
average of the anosmic group is very slightly lower than that of
the blind group, though here, too, the individual variation is high.
The average made by Male II of this group is the lowest made
by any normal or defective white rat upon the problem.
h. Average Time Records by Groups of Ten Trials.
The time-records of each individual were averaged by tens.
The interesting fact was brought out, that of the total of twenty-
six normal and defective animals, seventeen made lower
averages on the second, third or fourth ten than upon the fifth.
In other words: almost two-thirds of the total number of rats
reached their period of highest speed early in the series of
fifty trials, and later lengthened their time-records.
The average time-records by tens of the individual animals
are given below. The starred averages show those instances
in which the average time-record of a series of tens is shortest
before the last ten of the entire series.
TABLE SHOWING AVERAGES OF TtUE-RECORDS BY GROUPS OF TEN.
Blark-and-vibitt-ROi.
Individuals.
FEMALE 1 FEMALE H
FEMALE III
FEMALE IV
GROUP
■IS
1 ™/..
.16'
.11
.21
■ II-ZO
13
1 .06
.07
.07
.08
ll-JO
.06
1 -04*
.07
04
.05
31-40
OS*
■OS
.03*
■OS*
.04*
41-50
.11
1 .06
-04
.04
.06
DiBiiizcdb, Google
A STUDT OF SEKSORr CONTROL JN THE RAT.
Normal While Rait.
MALE I
MALE II
MALE in
MALE.V
AV. MALES
GROUP
I-IO
mi It.
"■45
r.36
1.08
.70
I. IS
1. 16
ii-ao
»3
.16
.11*
■IS
-14
a 1-30
■09
.12
■14
.19
-'3'
31-40
■09
.37
.12"'
■17
.'5
+1-50
.21
.21
•3
■IS
"4
FEMALE I
FEMALE 11
FEMALE III
FEMALE IV
AV. FEMALES
l-IO
1.08 '
.66'
.'5"'
2.02
1. 18
11-20
-14*
15
.07
.11
21-30
.19
.07
.16
.04
,11
31-40
.29
.06
-06
.11
13
41-so
■3S
■OS
.04
.12
MALE I
MALE III
MALE IV
AV. MALES
GROUP
l-IO
■S"
13
min.
.65
m,«.
min.
.89
■94
11-20
33*
■ 17
•H*
4'
21-30
.80
.28
.21
.21
■37
35
31-40
I.2S
.09'
.24
.41
■43
41-50
98
.10
.16
-15
■35
3'
FEMALE I
FEMALE II
FEMALE iV
FEMALE V
AV. FEMALE
-.0
I 53
150
■45
.66
•73
■97
11-20
1-38
I 17
.20
.68
.26
•S4
21-30
.81
.19
.24
■30*
.16'
34*
31-40
1.21
14
.21
38
.21
43
41-so
■09
.09
33
.24
.27
M»L. 1
MAUm
MALE IV
MAI.V
CROUP
"""■
't
3»
Soo
4'
I 43
■"'7'
11-20
.39*
.22
14
'5
.46
"7
2.-30
.42
.29
.10
.o8«
.28'
■'f
31-40
.fo
.20'
,olS-
.09
so
-^9
+1-50
2S
14
.11
•3'
DiBiiizcdb, Google
34 FIORMNCE RICHARDSON.
The occurrence of the minimum rime-records early in the
series may have been due to some accidental condirion, such
as a variation in the state of hunger. However, the beha-
vior of the animals as welt as their rime-records often indi-
cated a falling apart of the stages of the associadon, suggesting
rather a processofdissociadon, or dissolution of the association.
This might be the effect of a possible decrease in the intensity
of the Stimulus as the reaction became automatic. The matter
is commented upon here as seeming to be a situation in which
an habitual coordination tends to break down through a rela-
tively long conrinuance. In order to ascertain whether the rats
again would lower their records for later periods of ten trials,
or whether the coordination really disintegrated, the series
should have been conrinued indefinitely, and possibly should
have been controlled by changing the kind of food used as a
stimulus. Lack of rime prevented the continuation of this
problem.
c. Discussion of Errors in this Problem.
The computation of errors which were made by the animals
has been computed not upon the basis of the total number
of useless movements, but upon that of parricular kinds of
random movements, namely, those by means of which a rat
attempts to enter the food box from the east or west, whereas,
he can only enter from the north or south. In tabularing
the results, then, the attempts to dig away the sawdust at the
east or west is counted an error.
The number of errors is not alone an accurate standard in
the learning process of this problem. Often an error crops
out in a trial late in the series after the rat has made many
perfect trials. As an instance of this may be cited particularly
the case of one rat, black-and-white Female IV, which made
four errors, one each at her fourth trial, twelfth, thirty-fifth
and thirty-eighth trial. At the thirty-fifth trial her time was
somewhat longer, though at the thirty-eighth, with an error
at another position, it was at her reaction rime: .05 min. The
scratching in these last two trials might have been a move-
ment which was a reversion to her two early errors, or to an
Digi-izcclbyGoOgll
A srVDT OF SENSOSr CONTROL IN THE RAT. 2$
accidental movement set ofF by contact with the sawdust at
that point.
Rat IV of the anosmic group made but one error and that
at the first trial. Two black-and-white females made each one
error, at the sixth and ninth trials respectively.
The average number of errors for the different groups is here
given.
Average Total Number of Enort.
Normal Whice 8.2 Blind lo.
Black-and-white 3.7 Anounic 5.2
Average Number of Triali CbaraeterheJ by Errors.
Nonnal White 7.1 Blind 9.7
Black- and- white 1.5 Anotmic. . . . 4.. 4
d. Comparison of the Curves of the Different Groups.
Plate I shows the curves plotted from the average time-
records of the different groups. The curve representing the
group of black-and-white rats is the lowest curve of the four.
Even at the first trial, it does not rise above the coordinate
representing one minute, and for most of the time it runs below
that representing .i min. The curve is not only low, but is
remarkably uniform. Whether or not the lowness and uni-
formity is due to the fact that these rats possess pigmented
eyes will be discussed in the conclusions (p. 6i).
The curve representing the averages of the normal white
rats approximates more nearly than any other the character
of the curve representing the black-and-white rats. At the
first trial this curve is much higher, and, until the fourteenth
trial, does not reach so low a point as the curveof the black-and-
white animals. Again at the twentieth, the twen^-seventh
and the for^-fourth trials the curve goes below: otherwise, it
is higher and more variable.
The curves representing the averages of the blind and the
anosmic rats, respectively, are much alike and are slightly
higher than those of the normal rats. Both curves are irregular,
and both follow, in general, about the same level. The curve
of the anosmic group is considerably lower at the third, fourth
and fifth trials, than that of any other group of albino rats.
Digilizcd by Google
FLORENCE RICHARDSON.
From the sixth trial these curves cross and re-cross each other
continually.
B. TESTS UPON PROBLEM BOX II.
/. Description of Apparatus and of the Learning Process.
The apparatus used in the second test of the series consists
of a box, 20 cm. by zo cm. at the base and 15 cm. high, of
wire netting of a centimeter mesh. A door, 7 cm. high by
10 cm. long, is hinged at the lower corner of one side of the
box (see figure 2). A latch, on the inside is controlled by
a cord passing from the latch upward through a mesh above,
back over a small wooden pulley to the inclined board plane,
Fig. 2.
22 cm. long by 10 cm. wide, the foot of which rests at a dis-
tance of II cm. from the side of the box opposite the door.
The angle which the plane made with the floor of the experi-
mental cage was approximately 15°. This angle was decreased
slightly when smaller animals were used.
When the rat steps upon the plane, the plane falls, and the
latch is thereby pulled up allowing the door to fall inwards of
its own weight. In this test there is required a series of adjust-
ments on the part of the rat which is quite dtfl^erent from that
demanded oi him in Problem I. The question to answer is,
as was the case in the learning of the problem just discussed :
Does the animal use olfactory and visual impulses in the forma-
tion of these new and unusual coordinations, and if so to
what extent ?
Digilizcd by Google
A STUDY OF SENSQRT CONTROL IN THE RAT. 27
The method of procedure in this test followed closely that
just reported. ' The box was enclosed in a large wire control
cage 72 cm. by 76 cm. and 37 cm. high, which could be raised
when desired so as to admit the rat. The position of the box
remained constant, being determined by means of several
tacks in the table, which prevented the box from slipping.
The plane was also kept in position by tacks at the margin
nearest the box.
The animals which were used in Problem I were used in
the present test. All the animals thus had had previous experi-
ence in experimentation, and this previous experience was of
the same amount and kind. The results of other tests (see
p. 103) show this point to be one of importance in the control
of experimentation with rats. Three trials per day for ten
days, and live trials per day for four days were given, making
as before fifty trials in the series.
The solution of this problem is unique in that it necessitates
the reaction of the rat at a distance from the food box. On
this account, the learning curve from the second to about
the tenth trial is much more irregular than that of Problem I.
(See Plate II.) There is likely to be a second pronounced rise
in the curve after the first trials. This is explained by the
fact that after the Brst two or three accidental successes, the
rat comes to associate the position of the door with the food, but
not the position of the plane with the food. Consequent^', the
animal goes directly to the door, and Bnding it closed, begins
to scratch and gnaw at it vigorously. This is an almost
invariable procedure. The time so spent is the cause of the
rise in the curve.'
' The experimenter found it necessaiy to secure the latch Rrmly during the
rime the rat spent tugging at the door, for when the pressure of the door was
rdeated from thelatch, the weight of the plane raised the latch and allowed the
rat to reach its food without performing the desired reaction. At 6rst a hemp
cord was run through a hole in the table under the box and attached to the latch.
In this way the latch could be held 6rmly by the experimenter when necessary,
and loosened at once. Later when needed a long wire slipped between the
meshes of the cage and box and manipulated by the experimenter performed the
same duty more surely and more easily.
Digilizcd by Google
FLORENCE HICHSKDSON.
An account of the procedure of one individual is given here
as indicative of the learning process.
Dior
, ««W
/ Btack-anJ-Wbiu Ftmah I on Prvhiem Box If.
TRIAL.
6/5/07
6/6/07
6/7/07
6/8/07
6/11/07
I
3
4
1
7
8
9
10
18
Went at once to door of box, lan around box rapidly
noppingonlytoiniffatfood; struck ihe plane once,
ran about cage. Door fdl at 2.33 min. without
attracting her attention; «he found opening at 3.07
min. and entered. Time: 3.07.
Worked ai door fiercely and penistently, occaiionaliy
dashed around box. Door fell at IXM min.. in at
To door first, then round and round box several times.
Plane fell at 1.50 min., in at 1.55 min.
Very aaive, but confined activity too near to box. In
at once after door fell. Time: i.^Smin.
Stayed too close to box. Time: 1,78 min.
Had bad luck; was almost too active; jumped over plane
or went around it. Door fell at 8-53 min. The rat
got up on food box and spent much time in sniffing
the air. Entned at 11.80 min.
Door fdl at .67 min., in at .72 min.
Door fell at .80 min., in at .88 min.
See sixth trial. Time: I.38 min.. in at 1.50 min.
Door fdl at .07 min., in at .10 min.
E>oor fdl at .03 min., in at .06 min.
Rat went directly to door, then to plane, then back to
door at once. Door fdl at .13 min., in at .17 min.
Went as usual directly to plane and over it, but too
went to door, came back to plane at once, over and
to the then open door. The association seems
firmly fixed. Time: 18 min.
The record of this black-and-white rat was chosen because
as a whole it was more typical than that of any other individual
of the manner in which the association was formed, though
the time records are lower than the records of an average
normal rat. This rat, too, learned the problem in fewer trials
than the average normal rat: indications of the soh.tion were
observed in the 12th trial, in which there seemed to appear
Digilizcd by Google
A STVDT OF SENSORr CONTROL IN TBB RAT. 2^
die association between the door and the plane. In this trial
there were no useless movements. There was little doubt that
in the eighteenth trial the association had become fixed.
The above records of the individual rat serve to call attention
to the nature of the learning process involved in this test. We
have (i) random movements; (2) the accidental successes from
which the animal at first profits little; (3) the elimination of
useless movements; and (4) the completely established habit.
The elimination of useless movements in this test is accom-
plished in much the same general fashion as in tests of the
labyrinth type. In the former, however, the rat runs about in
an open space, whereas in the latter his pathway is restricted
by the side waits of the galleries. Therefore the random
movements in the present case survive for a longer time than
in the labyrinth, because there is greater opportunity for, and
a greater variety of, them. As was stated, the rat usually goes
first to the door, then about the cage and to the plane and back
again to the door. Ordinarily this routine continues until
about the thirtieth trial, after which the movements are in a
great measure automatic.
The animals, as was stated earlier, tend in their habitual
reactions to go to the plane, thence to the door by a definite
route, which varies with the individual. An unusual turn in
leaving the plane to go to the door may so utterly confuse
them, that to run back to the plane and to start over is the only
apparent manner of taking up the trail. This is a very fre-
quent occurrence, and among the last trials is almost the sole
reason for a high time record.
2. Statement of Results.
a. On Normal White Rats.
The group of normal white rats was first tested upon the
problem.* The averages of the group, four males and three
' The proUem box at the banning of this test wsa not of the tame fottn ai
described here. The plane wai set immediatdy at the north end of the bcHC,
Duicad of 1 1 cm. distant, and the control cage was the Email one used over Box
I, innead of the larger one latei used. The original conditions made the prab-
lem mudi earicr of solution than the experimenter desired. Radical moditica-
Digilizcd by Google
JO FLORENCE RICHARDSON.
females,' are given in Table V, following the form of the pre-
vious tables. The graphical representation of the averages
given in Table V is shown on Plate II.
The column showing the minimal time-records at each trial
indicate how quickly the problem can be solved. For the
last ten trials the minimal time runs but little over .03 minutes.
The curve constructed from the group averages at the succes-
sive trials shows the second rise at the third and fourth trials,
which is due to the length of time spent by the rats in going
directly to the door of the box and trying to push it open.
Table V.
Sbtnviiig tbt anrragt, the mimimum and the maximum limr-rteorJt of stven
normal white rati Hfom Problem II. Tbt tart tbrtt tolumm shtmi the number
of oHtmali wboif records art {/) tquid to the average, {z) beloti/, and (3)
above tbe average.
NO. OF
IVIAL.
AVBRACB. HIN
HUH.
HAXmUH
I.
a.
3-
,
" 88
25
,".'56
4
3
2
1
42
04
49
4
3
3
2
35
04
22
S
2
4
1
54
15
74
S
2
5
80
03
6
I
6
7»
09
08
5
2
7
95
06
40
6
I
8
27
08
42
5
2
9
20
03
47
5
2
10
20
07
37
4
3
"
49
63
'
20
4
3
tioni were made accordingly: the plane was moved out eo a distance of 11 cm-
and a Urge control cage nas put over the problem box. The rats, however, had
had two dayi experience with the original box. The above records are all taken
from tests with the modified box. It is impossible to estimate what was carried
over from the old situation to the new, therefore the records may not be quite
fairly companble to those of the rats which folbwed; yet this faa does not
detract from the utility of the curve as a whole.
' Female I learned (o open the door, not by stepping on the plane, but by
tu^ng at the cord which attached the plane to the latch. From about the
thirtieth trial the not only tugged at the cord until the door fell, but continued
to tug; so that her time-records were too variable to be included in the average.
Digilizcd by Google
A STUDr OF SENSORr CONTROL IN THE RAT.
Table V.— Continued.
NO OF
1
TRIAL. ^"^
tACE. HINIHUH. iMAXa
uu.
I. [ 2.
3-
" 1
l<i 1
67
47
6
■3 I
3° ;
67
62
U
12
57
25
'5
21
67
5»
i6
26
08 I
03
^
17
13
05
20
|8
07
05
10
19
14
04
67
20
08
05
33
21
14
OS
SO
6
«
09
04
17
4
'3
12
04
40
24
08
03
18
»S
05
03
10
>6
22
04
62
27
■3
03
SO
28
10
04
27
»»
14
03
33
3»
12
03
25
31
18
03
38
3^
>S
06 1
33 i
33
14
02
52
3*
08
05
■ 8
3!
11
07
17 1 I
!«
12
03
25 I
37
08
04
II
2
38
07
03 1
10
39
07
04
12
I
40
09
04
23
1
41
OS
02
08
1
42
19
04 1
88
43
12
03 1
«7
44
06
03
4S
10
03
20
I
46
as
03
16
3
47
07
04
22
48
M !
°3 ,
12
49
oS :
03 t
II
2
SO
08 ;
06 1
>3 j I
4
The following table shows the percentage of minimal and
of maximal dme-records made by each of the rats in this group.
Digilizcd by Google
Jl FLORENCE RICHARDSON.
TABLE SHOWING PERCENTAGE OF MINIMAL AND OF MAXIMAL TIHE-RECORDS
MADE BV INDIVIDUALS.
Minimal. Maxim tJ.
per cent. per ctnl .
Male 1 12 Male I iz
Male II +0 Male II 8
Male III 9 Male III lo
Male IV 8 MalelV 12
Female II 11 Female II 8
Fonale III 16 Female 111 31
Fmiale IV 4 Female IV 19
b. On Normal Black-and-White Rats.
Table VI and the curve on Plate II show the records of the
group of four Black-and-white females. These rats were so
incessantly active that it was often quite difficult to hold them
in the hand. Because of this superabundance ofenergy their
early time-records were short. They gave evidence also, as
remarked above, of having acquired the association earlier
in the series than the normal white rats, whose records were
unfortunately rendered ambiguous for the comparison.
After the thirty-fifth trial, the rats received a fright, probably
due to the odor of wild rats about the cage. They were so
disturbed upon being introduced into the problem box that
the final abandonment of the series was necessitated. Their
reactions had been practically constant in their last fifteen
trials, so that little was lost to the experiment.
The following tabulation shows the percentage of minimal
and of maximal records of each animal.
TABLE SHOWING PERCENTAGE OF MINIMAL AND OF MAXIMAL RECORDS OF EACH
INDIVIDUAL.
Minimal. Maximal.
Female 1 36 Female 1 26
Female II 17 Female II 21
Female III 31 Female III 25
Female IV 16 Female IV 28
The percentage of maximal records, as indicated above, is
very evenly divided among the four animals. Females I and
Digilizcd by Google
A STUOr OF SBNSORr CONTROL IN THE RAT.
Table VI.
Shoaling the averagi, the minimunt and the maximum timt-recorii of four
Uatk-and-vibite females upon Problem II. The latt tbrtr toiumai show
the mamter of aaimalx wboft recordt are (/) equal to the average, (l)
Mout, amd (5} ^mie the average.
NO. OF
imiAL. *"
RAGE. HIN
WUH. MAX
■HUH.
'•
*■
3-
W."».
nin
„,„
1 I
53
78' 3
07
3
2 I
70
63 1
53
2
3
73
22 I
56
+ '
02
70 1
S7
5 1
63
47 2
78
6 4
'7
27 II
80
7 '
10
72 1
57
8
87
18 1
70
9
90
23 1
50
I
10
78
10 1
62
11
37
06
92
12
48
■7
96
'3
28
58
'4
35
25
S8
'S
39
05
67
16
22
II
37
17
30
08
66
18
18
'3
'5
'9
*1
"4
35
10
■6
'3
21
21
IS
»7
3"
22
12
»7
25
»3
07
H
II
o«
23
15
07
06
08
26
'3
07
18
I
27
14
06
37
28
'4
07
28
29
'4
07
30
y>
16
09
24
31
II
"5
■7
3»
14
»5
3"
33
09
05
14
I
34
•3
10
16
35
H
08
18
DiBiiizcdb, Google
34 FLOBZNCB RICHARDSON.
Ill together made two-thirds of the entire total number of
minimal records.
c. On Blind Rats.
Table VII and the corresponding curve on Plate II show
similarly the average records of six' blind rats on Problem 11.
The behavior of the blind rats was characterized by a lack
of eagerness, although when first introduced into the control
cage they were most anxious to get into the food box; if they
were not successful soon their activity abated, and random
movements characterized their efforts. They were slow in
forming a pathway, and in several instances no definite padi
was chosen.
The percenuge of minimal and of maximal time-records of
forty-four trials^ for each of the blind rats is given below.
TABLE SHOWING PERCENTAGE OF MINIMAL AND OF MAXIMAL TIME-RECORDS
MADE BY EACH INDIVIDUAL.
Minimal. Maximal.
percent. per cent.
Female 1 9 Female 1 38
Female II 14 Female II 26
Female III 19 Female III 7
Female IV 29 Female IV 9
Female V 21 Female V 2
Male IV 2 Male IV 18
d. On Anosmic Rats.
As before stated all but one of the anosmic rats died before
the experimentation had been completed.* The one that
remained was set to work on this problem,* He learned the
association perfectly, but invariably pressed down the plane
> Males I and III had died of an mfection.
' Female II became ill, and did not work arter the forty-rourth trial, con-
sequently the percentage after this trial is not considered. Male II manifened
a decided repugnance to approaching the plane, as the falling of it had apparently
frightened him; therefore he did not learn the problem.
' The infection becann apparent just after the animals had completed their
worlt upon Problem I, and they died almost immediately after.
' He was the tat which gnawed at the wire in the sawdust box.
Digilizcd by Google
A STVDT OF SENSORY CONTROL IN THE KJT. 35
Table VII.
Sboimmg tbe average, the minimum and the maximum lime-rtcordt of six Uind
rats upon Problem II. Tbe latt three columns ibow tbe number of animals
vibose records art {j) t^uid totbe aaerage, {z) belaio, and (j) above tbe average.
NO. OF
TXIAL.
AVERAGE.
MINIMUM.
MAXIMUM.
'■
2.
3-
,
mill.
1.3a
■52
2'. 08
3
2
» 47
■23
2-75
2
4.09
5»
".37
2
8.37
.12
4580
I
a-37
43
7.57
2
2.12
.30
4.03
a
3 47
47
8-59
2
.68
.12
4 17
2
« 93
07
.62
2
1.70
1.22
.10
.la
5.19
4 33
8.52
2
2!o8
■25
8-45
2
3-34
■55
12.03
a. 85
.22
12.67
I
I 04
■15
2-39
2
1. 71
.12
4 13
■83
■38
1. 52
2
i.aa
.28
Z.62
3
• 55
.38
a-33
3
1. 18
.10
4-05
2
1.0+
■47
1.97
a
I 3S
.26
350
2
'■77
.a8
+■67
3
.96
.a8
1.87
3
a6
I. II
.08
2.42
3
27
.68
■as
'-'3
2
2
aS
.48
'3
• -93
2
29
1.0+
■'5
1. 18
3
30
1.1+
,18
1.58
3
31
a,o6
-40
2.92
3
J»
2.80
■ 17
15.12
33
.70
13
1.72
2
34
1.41
■'7
3 57
3
35
.08
-a?
I -85
3 ■
36
1. 10
32
a. 67
37
1. 18
■45
367
I
38
1.48
-57
1.80
4
2
DiBiiizcdb, Google
FLORENCE RICHARDSON.
Table VII.— Continued.
Ma OF
TOUt. "»
lAGE. MIN
[MUU.
MAXIMUM.
'■
^■
3-
39 "
45
iS
3«7
3
♦0
97
■5
2.88
2
+'
83
:8
1.03
4
+2
59
1. 12
3
43
84
1. 10
44
73
253
4S ■
II
2.S0
46
21
317
47
75
1 75
48
40
.85
49
'3
22
S"
70
18
1.52
while gnawii^ the string which connected the plane with the
box. When he braced himself to gnaw, the pressure of his
forefeet upon the plane was instrumental in pulling up the
latch. He continued to gnaw until he had completely severed
the string from the plane. After the thirty-third trial he in-
variably ran at once to the door when he had Bnished bidng
at the string or plane. If he did not find the door open, he
went back to the place and his gnawing, and after another
effort scurried to the door again. Wire was substituted for
cord, whereupon his task was seemingly endless, and he varied
his procedure by dragging the plane about the cage. Table
VIII shows the records of this rat. The time-records of the
later trials are shown as they were taken, giving the length
of time consumed by the rat in different parts of the cage.
In learning the problem, this rat did not spend the greater
part of the time in the early trials — as did the rats possessed of
the sense of smell — in sniffing at the food through the meshes
of the wire covering of the problem box. The rat did lose
much time, however, in trying to get into the box by tugging
at the door.
For the first six trials the time-records of this anosmic rat —
with the exception of the second — are below one minute:
four of them are below .50 min. His long time-records in
Digilizcd by Google
a studr of sbksorr control in the rjt. 37
Table VIII.
Stowing lb* limt r*tordi of the anotmie rat an Problem II.
SGIKa
1. DOO. FALLS. 3- ™
B FROU
GNA
nriNO.
PLANE
no DOOR.
I
.».
■2J
T
♦3
1
75
35 I
10
3
10
ao
40
4
37
07
44
5
41
05
46
6
33
63
96
7
I
4a
63
OS
8
3
33 '
03 4
3«
9
25
3«
63
10
2
25 I
oa 3
a?
II
28
ao
48
la
10
66 t
33 la
00
■3
08
o«
16
14
I
00
la I
la
15
13
35
58
16
48
5«
06
■7
I
65
73 a
38
18
1
05
45 I
SO
19
1
92
5» 3
4a
ao
66
88
ai
a
as
3= a
55
aa
83
as ■
08
a3
33
08
41
u
20
'7
37
'5
I
25
■3 1
38
16
I
33
31 I
6S
a?
I
25
38 I
S3
a8
■3
35
a*
3>
48
80
3=
I
2^
as 1
a8
31
I
80
3a a
la
3a
92
a5 1
"7
33
2
53 a
67
34
83
■5
98
35
22
5»
7a
3'
50
ao
70
37
06
1
63
03 I
66
38
20
85
OS
90
39
08
I
42
05 ■
45
40
OS
50
03
S3
41
03
I
08
"3 I
II
4a
18
I
40
08 I
4«
43
07
67
°3
70
44
2Q
83
03
8S
4?
03
63 I
02
65
b, Google
3? FLORENCE RICHARDSON.
the later trials were due to his gnawing propensities. The
time which he spent in going from the entrance to the plane,
or from the plane to the food box was not longer than that of
the average normal rat. In the last nine trials the average
time from entrance to plane is .10 min., and from plane to
door .04 min. Disregarding the time spent in gnawing, his
average time would be .14 min., for these trials; which may
by a glance at the curves be seen to be but little longer than
the average time-records of the normal rat, and shorter than
the maximal time'tecords of that group.
3. Effect on Rats of Changing Position of Plane go° to Right.
After the group of normal white rats had completed ihis
series, the position of the plane was changed, being placed
east of the box, instead of north as before. The reactions of
the animals had become practically habitual before the change
was made. It was thought that the change in conditions
might bring out two facts regarding the behavior of the
animal: (i) The nature of the sensory control in the habitual
act; (2) the nature of the sensory data by means of which the
modified reaction which is necessary under the changed con-
ditions is built up.
Since the rats in this series were put always into the cage
from the east, their established pathway carried them within
two or three inches of the longer side of the plane. Each of
the four males was tried in turn, and each went directly to the
old position of the plane, then ran to the door. One of them.
Rat III, seemed confused at not finding the plane in the
usual position. The other three went to the food box as though
not missing the link in the series. Their confusion began at
the door. Each rat, after running about in a seemingly aim-
less manner for a few seconds, struck the plane and the door
fell. Rat I could not seem to find the way to the door, even
though something connected with the falling of the plane made
him frantically eager to get back to the box. He finally
went over the box. On the third trial he proceeded slowly
and kept his nose to the floor {discovering the plane by touch ?).
From the fourth to the ninth trial he passed over the plane
Digilizcd by Google
A STL'Dr OF SENSORT CONTROL IN THE RAT. 39
direcdy on his way to the door. On both the ninth and tenth
trials, he reverted to his old habit of going at once to the orig-
inal position of the plane on the north. Rat II reverted to
the old habit similarly in the ninth trial. Rat III went to
the door first, except on the seventh and ninth trials when his
route accidentally took him far enough south to touch the
pbne. The slight contact seemed to give him immediate
orientation, for he ran across the plane and to the door at once.
Rat IV was the least confused. He ran to the old position
but did not go to the door. Instead, he began wandering
about and strayed across the plane in a seemingly haphazard
fashion, but the instant it fell the old habit reasserted itself
and he dashed off to the door. At the second trial he went
directly across the plane to the door. All his other trials were
almost precisely like his second. His records were quite phe-
nomenally quick after the first trial, not going above .03 min.'
This test furnished some evidence upon the two facts sought
for, i. e., the sensory avenues of control in the habitual act, and
the sensory avenues of control in the process of readjustment.
The habitual act seems to be carried out by means of the guid-
ance of kinaesthetic impressions. The rats traversed the old
pathway even when such movements did not lead to the suc-
cessful solution of the problem. The old coordination broke
down apparently in the case of these animals when they found
the door closed; the fourth (Rat III) seemed to become con-
fused in not getting the 'cue' at the plane itself The question
of the probable nature of the cue is discussed later in the sec-
tion (p. 40).
' The case of Rat IV seems anomalous. The records bear evidence to
the fact thai the pathway of this rat in solving the original problem was
Tariablc- In seven out of the ten trials just preceding the change in the appara-
tus, the animal went fim to the door, then to the plane. In the first trial after
the change, he departed from his former custom of going first to the door, and
instead went direct to the plane. His confusion at that point was no greater
than he had often previously displayed in picking up the trails. On the second
trial and on all thereafter, he resumed his old habit of going at once to the door;
the result of which was that he threw the plane en-route as it was directly in his
pathfrom the entranceofthecagcto the door of the food box. This explanation
accotinis for the ieeming variation. It was simply a case in which the failure
of the rat to acquire a stereotyped mode of response to the old situation made
tbe adjuftmeni to the new situation less difficult.
Digilizcd by Google
40 FLORENCE RICBARDSON.
The new coordination necessary in the readjustment to the
changed situation is built up on the sensory data by means
of which the plane becomes the stimulus to the further coor-
dination involved in running from the plane after it has fallen
directly to the door of the food box. In these cases [i'. e.,
the inclined plane] the basis seems to be that afforded by
touch. Q>ntact with the plane was doubtless the evidence of
its presence. Had some distance sense factor such as vision
given the cue, it would seem that the animal would have had
less difficulty in finding the plane in the new position which
was at such a short distance from the old position. It was
only when they came in contact with the plane that some sen-
sory impulse connected with its fall set off the old association
and they would dash to the door of the box. 7*he new path-
way was easily learned, though, as remarked above, not closely
adhered to as three of the rats on later trials made errors in
favor of the old pathway.
It had been a part of the plan of the work to further modify
this test, but it was found later that the conditions of the
learning process had not been sufficiently well controlled. In
a test of this kind the rats should have learned the association
in an environment every part of which was equally illuminated,
so that a change in the apparatus would involve no change in
brightness values in different portions of the field. The con-
trol cage should have been lined with canvas or other opaque
material so as to preclude the possibility of orientation by means
of distance sense factors. On this account a test involving
such modifications as have been here made are not conclusive.
The results are suggestive; and if the test were properly con-
trolled it would be of value in isolating the different sense
factors which function in forming the association.
A problem of especial interest which arose in carrying out
the above work is that of the sensory avenue by means of which
the rat obtains the cue for the run to the door after the plane
has fallen. In the early trials of the test it seemed quite suffi-
cient for the rat merely to run past a certain point on the
fioor of the cage. Indeed, many rats never appear to get
beyond this method of reacting. But occasionally a rat hesi-
Digilizcd by Google
A STVDT OF SENSORT CONTROL IN THE RAT. 41
tates at the plane apparently until he gets a cue that the
door has fallen inward. In such instances the cue may be:
(l) The sound of the falling door; (2) the molecular vibrations
(tactual impressions) set up in the wood by the door as it falls
upon the floor of the cage; (3) the jar (kinaeslhedc and pos-
sibly static) of the falling plane.
Male III was an animal which did not seem to require such
a cue. Several times in the last ten trials this animal would
run to a position about one inch west of the plane, rear up
slightly, and assume the crouching attitude which he had been
accustomed to assume on the plane itself and would then dash
back to the door. He had thus gone through all the move-
ments of throwing the plane, except that he had not performed
them on the plane. He was completely confused when he found
the door closed. This rat at least, evidently oriented himself
according to the relative position of the plane. The tactual
element in the experience seemed of no value while the kin-
aesthetic experience of raising the forepart of the body and
lowering it was apparently the esssential feature. This kJn-
xsthedc series was sufficient to set off the sequent coordinations.
The failure of the animal to react to the plane itself when
almost touching it and when to all appearances attempting to
react to it, is'typical of the earlier trials of practically all of the
rats. There is no evidence whatever that the rat perceived
tlie plane or that the plane comes to be an isolable portion of
the problem box situation. A rat, when attempting to get
into the food box, runs around the box in varying circles.
In one of these circles he runs over the plane and when he hurries
back to the door, as he does after every peregrination, he finds
it open. Many such trials are necessary before he establishes
a pathway which includes in its course the crossing of the
plane. This seems to indicate that the reaction of the animal
to the plane is determined by kinesthetic data and that the
kinesthetic experience at this point is the stimulus for the
further movement, namely, that of ^turning to take up the
pathway to the door.
On the other hand the behavior of Male II of the same group
indicates a different kind of series of stimulations at the plane.
Digilizcd by Google
FLORENCE RICHARDSON.
His path led him out upon the plane, rather than across it.
On his forty-fourth, forty-eighth, forty-ninth and fiftieth trials
he crouched near the margin of the plane nearest the cage,
but as he was not far enough away from the inner margin, his
weight was not sufficient to press down the plane, and conse-
quently he could get no report. He then took another step
further out and waited. Usually the door fell after his
second step. It happened once on the forty-ninth trial that
a third step was necessary to press down the plane, ^^'he^
this step had been taken, and the door had fallen, he hurried
off to the food box.
It is not easy to postulate just what happened in the case of
this rat. It is evident that some form of sensory data, probably
auditory, combined possibly with tactual, kinaesthetic and
organic, gave the cue to the succeeding coordinations.
^. Summary,
a. Average Time-records for the Total Series.
The average of the total time consumed both by the indi-
viduals and the groups is given below. The group averages
are given only for the first thirty-five trials, by reason of the
fact that the group of black-and-white rats were unable to
finish the series of fifty trials.
TABLE SHOWING THE GROUP AVERAGE OF THE TOTAL TIME (THIRTY -FIVE TRIALS)
CONSUMED BY NORMAL AND BY DEFECTIVE RATS IN LEARNING FROBLBH II.
Average by Grou^i
Normal White 48 Blind i .48
Nomial Black-and-Whiie 49
TABLE SHOWING INDIVIDUAL AVERAGES OF THE TOTAL TtMB(55 TBIALS) CON-
SUMED BY NORMAL AND BY OEFBCnVB RATS IN LEARNING PROBLEM II.
Normid Block-anJ- Wbiu
Blind.
Male 111..
Male IV..
Female ]
Female I]
Female 1'
Female 1 77
Female 11 44
Female III 51
Female IV S'
Female I
Female II
Female ill
Female IV ... .
Female V
Male IV
Digilizcd by Google
A STUOr OF SENSORr CONTROL IN THE RJT.
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FLOKENCE RICHARDSON.
There is practically no difference in the averages of the
group of the white and of the black-and-white animals. The
average of the group of blind rats is much greater than that
of the normal rats.
The variation among the averages of the individuals is con-
siderable. The high records of the normal white Males II
and IV, were due to high time-records in the first ten trials.
The averages of the normal white females are all lower than
the lowest of those of the black-and-white group. Blind Females
IV and V and blind Male V, made averages lower than the
maximum individual records of either the normal white or
the black-and-white groups. There is greater variation among
individuals of this blind group than among those of any other
group.
b. Average Time-Records by Groups of Ten Trials.
The following tables show the averages of the records of
the series by groups often trials each. The averages are given
for the individuals, and for the groups. The starred records
show those instances in which the minimal record for a series
of ten was reached before the last series of ten.
Normal fFhitt Rats.
INDIVIDUALS.
TRIALS.
MALE 1.
MALE II.
MALE III.
MALE IV,
t-IO-
■64
Tbj
.62"
2.27
ii-ao
■ M
'7
.08*
.08
21-30
.IC-*
.05'
■>3*
.os»
31-40
.11
■05
09
.10.
41-50
■07
'3
.09
FEHALE t.
FEMALE 11.
FEMALE III.
FEMALE IV.
r-io
I,l6
■79
.96
1-44
11-10
.10
43
■14
.19
21-30
.12
■V
■17
'3
31-40
.09-
,09
.11
41-50
■«7
■'7
,08
.10
DiBiiizcdb, Google
A sTVor or sensort control in the rat.
BJack-and-fFbiti RaU.
FEUALEI.
FEMALE 11.
FEMALE III.
FEMALE IV.
l-I
2.28
1.03
1.19
1.19
1,42
■H
•s
-47
32
29
JI-30
'3
.08-
.18
'3
3'-3S
■3
■»9
.09
.12
FEMALE
MALE
IV.
V.
IV.
OROUF.
1-10
2.96
■5>*
1.23
8.34
1.12
'■'J
= ■85
11-20
4.50
.74
1.23
.6,
1.77
21-30
■ 43
2.00
1 13'
.29'
1.00
..07'
31-^0
2.81
1.99
1-28
.46
-«4*
■■35
41-50
l.Il
1.28
-40
7.80
2.23
Here, as in Problem I, many rats — in this case ten out of
a Mtal of seventeen animals — made their lowest averages before
the last ten trials of the series. This peculiarity is especially
noticeable in the above records of Blind Female 11 whose first
group of ten averaged considerably less than any later ten.
The blind group is the only group whose total average shows
the minimal average by ten near the middle of the series.
c. Comparison of the Different Groups.
The curve showing the average time-records of the group of
normal white rats is lowest at the first trial, from the fifth to
the eleventh trials, and from the seventeenth to the twenty-
fifth inclusive.
The curve of the black-and-white rats has a very pronounced
rise at the sixth trial; otherwise it is more r^ular in contour
than that of the group of the normal white rats.
The curve representing the blind rats is exceedingly high and
irregular though at the first trial it is lower than any other, and
at the second trial is below that of the black-and-white rats
and but little above that of the normal white rats. From the
eighth trial this curve does not descend to the level of the
curve of the normal animal.
Digilizcd by Google
46 eLORZNCB RICHARDSON.
C. TESTS ON PROBLEM BOX III.
/. Description of Apparatus, and of the Learning Process.
The third problem box submitted to these same groups of
rats was the familiar one necessitating the raising of a latch.
As in the two previous problems, the animal enters the box
for food. The box consists of a wooden frame, 14.25 cm. in
height, ao cm. in length and 20 cm. in breadth. The frame
is covered with wire netting of one centimeter mesh. The
spring door, 6.25 cm. high and 10 cm. wide, is so fastened to
the bwer left hand comer of one side of the box, that when the
latch which holds the door in place is raised, the door opens
outward. (See figure 3.)
F'g- 3-
The control cage which was placed over the box is the same
size as was used over Box I. A morsel of cream cheese —
always of one commercial brand to insure constancy of taste
and of odor — was rubbed on the back of the latch at the begin-
ning of the series of trials. The combined taste and odor
served ta attract the interest of the rat, the effect of which was
to lower the absolute time records of the first trials. The use
of this device does not alter the general form of the learning
curve, nor influence the later time records.
The unusual coordinations involved in this test are those
connected with finding the door and raising the head to lift
the latch. The animal may Hft the latch either with its teeth,
snout or claws. The rapidity of the solution depends in the
Digilizcd by Google
A STUOr OF SENSORr CONTROL IN TBE RAT.
47
first few trials largely upon the particular type of movement
adopted by the rat in opening the latch. The animal which
lifts the latch with its snout is likely to make the shortest time-
record, in view of the fact that this movement requires fewest
muscular coordinations.
The diary notes are given as the most concise and satis-
factory description of the learning process.
ATm^/ on ih
t Bfbaoior of Normal Male Rat III in Uarning Problem III-
TRIAL.
6/2/06
6/3/06
a
3
*
5
6
The sprin| interens him; nandt on hii hind legs and pulls
inner end of latch. Crawled in over top of door.
Time: i.io min.
Same procedure ai above, but animal more active.
Time: .13 min.
Repeated above: Time: 1.25 min.
Leaves spring to gnaw at latch; pushes down inner end
of latch as before. Time: .13 min.
Raises latch with teeth. Time: .15 min.
As above. Goes in oi«r door each time. Time:. 12 min.
This particular rat crawled either over or under the door
in entering the food hox until the end of the series. Most
of the rats discovered the easier method of entrance, and a
number of them learned to raise the latch from the left, and
saved themselves the annoyance of a blow from the opening
door. In a number of instances the rats became wary about
entering the box on account of having been struck By the door.
Many long time-records near the beginning of the series are
to be explained in this manner. Individual variations in the
animals' methods of solving this problem are more noticeable
here than in any of the other problems.
2. Statement of Results,
a. On Normal White Rats.
Table IX and the curve on Plate III show the averages of
the time-records of the group of normal white rats upon this
problem.
Digilizcd by Google
4B FLORENCE KJCHJRDSON.
The group at this time consisted of four males and two
females.*
Tablb IX.
Showing iht average, the minimum and the maximum lime-recorJi of tix normal
white roll an Problem III. The lajt three columai ibout tie numher of
animoii whose rreorJt art (/) t^ual to the average, {2) beiow, and (5) above
the average.
»<,.„,
AVERAGE.
MAXIMUM.
2-
3-
TRIAL.
min.
min
min.
5.72
1.87
9.48
3
I
32
.08
55
3
3
■33
.02
I.2S
I
+
■'7
4
S
■■")
.08
-87
1
6
.11
■ 37
2
7
09
.04.
."4
3
8
-09
05
>S
I
9
.06
03
.08
3
10
.06
■03
.08
2
11
.07
.OS
.11
I
2
12
■OS
■03
.0;
2
I
'3
■OS
.02
.07
3
H
OS
0*
.06
2
I
■S
■05
■03
.08
'
These rats did not discover the door in the lirst trial; but
at the second they went almost immediately to it and bit and
clawed at the latch and spring with great energy. By the
end of the series, each rat had learned to lift the latch with
its snout, and most of them raised the latch from the outer
margin and were thus out of the way of the door when it flew
open. The individual records are very uniform. At the
fifteenth trial the coordinations were perfect and had become
habitual. The experiments were therefore discontinued.
'This group has been reduced in numben. Female III died, and Female I
who was slow in Problem I, slower in II, and very slow in ihe present problem)
made such uniformly poor records that they were omitted in theaver^gc.atthq'
represented a very marked variation. She made the maximum time-record in
every trial. Her time-records are given and discussed in the section on individ-
ual variations.
Digi-izoclbyGOOgle
A STUOr OF SENSORr CONTROL IN THE RAT. +9
The following table shows the percentage of maximal and
of minimal time-records made by each animal.
Min
Male I
Male II
Malell! lo
MalelV 34
Female II o
FonalcIII o
46
Maximal.
per an
Male I O
Male II o
Malelll 13
MaielV 27
Female II ^
Female III 20
Neither of the two females made a minimal record during
the series, and neither Male I nor Male II made a maximal
record during the series.
b. On Normal Black-and-White Rats.
This group had also been reduced in number. Females I
and II died at the end of tests upon Problem Box II. Table
X and the curve on Plate III show the records of the two remain-
ing animals.
Table X.
Sbvmimglbi AverageTime-recordl of Two Black-and-fFbile Rati on Problem III .
NO. OP TKIAL.
NO. OF TRIAL.
Digilizcd by Google
FLORENCE RICHARDSON.
The records of these two rats are very low, and very uniform.
The first successes were achieved in remarkably short time,
all of the averages being below one minute. In the later trials,
each rat, in its eagerness to get to the door, sometimes dashed
past it, and went on around the box, thus lengthening the
time-record.
The percentage of minimal and of maximal time-records
made by each rat in the group is shown below.
PERCENTAQE OF MINIMAL AND OF MAXIMAL TIHE-RBCORDS
Minima}. Maximal.
ptrcent. per cent. ,
Female III 30 Female III ;o
Female IV 70 Female IV 30
c. On Bhnd Rats.
The behavior of the blind rats was strikingly at variance
with that of the normal rat in this problem. Their time-
records were long and inconstant. Practically all of the rats
suffered an emotional shock from the quick opening of the door
. when the latch was raised. The blind animals were not alone
in receiving a fright at the blow of the door. One norma)
rat became so cautious in his attempts to raise the latch that
his efforts in going up to the latch, springing back, stepping
up cautiously again, and again rebounding, came to be ludic-
rous in the extreme. On one occasion the unsuccessful efforts
of a blind rat to raise the latch were counted. Thirty-three
times she approached the latch and thirty-two times she re-
coiled like a tight spring! Only at the thirty-third attempt
did she exert enough pressure to lift the latch, and when the
door flew open she seemed paralyzed with fright for several
seconds, and did not attempt to enter the box. When she
finally entered she caught up a mouthful of food and ran out-
side to devour it. T^is state of high emotional tension is
one cause of their poor time-records, particularly in the early
trials.
The following table, Table XI, and the curve on Plate III
show the time-records of the group.
Digi-iz^cll^vGOdgle
A STUDT OF SENSORr CONTROL IN THE RAT.
Table XI.
Showing the average, ibt minimum and the maximum time-records of three blind
rats on PrMem III, 7belait three columni jhau/ the number of animtJi
whore retards are (l) equal to the tiwrage, {2) belotv, and (5) above the
-"" »..
lAGE. MIN
MUM. MAX
IMUM.
3.
nuAL.
™.
in. IT
...
' 7
32 3
95 9
23
■ 3
93
.8 9
37
3
57
28
75
4 2
59
45 6
07
S 3
79
92 7
28
6 I
90
22 4
95
7 ■
78
•5 4
'5
8
95
35 I
70
9 1
3"
48 2
35
10
92
53
12 1
38
42
77
12
53
'7
80
'3
60
20
78
'
14
30
■ 2
34
>S
10
12
28
16
3"
25
3S
I
'7
19
10
30
18
17
II
23
•9
51
20 I
'3
20
'9
07
30
12
28
30
22
37
45
23
21
20
35
24
23
10
30
2S
25
12
J5
26
18
'3
25
27
27
23
33
28
■4
08
25
29
18
10
28
3»
28
17
38
I
3'
34
22
45
32
26
12
35
33
19
08
35
34
3«
10
83
35
30
'7
43
1
3*
29
■5
47
37
44
72
2
38
33
08
55
2
39
27
05
40
I , 2
40
23
18
26
1 1 2
DiBiiizcdb, Google
52 FLOSBNCB BICHABBSON.
The blind rats were slow in attaining their first successes,
and in establishing a pathway from the entrance of the cage to
the door of the food box. Several rats did not establish a
definite route even after forty trials. In these cases the behavior
of the animal throughout the test suggested the random activ-
ity of early trials.
The table given below shows the percentage of minimal
and of maximal time-records made by each rat.
Minimal, Maximal.
fertent. frr cent.
Male IV 51 Male IV 23
Female IV 34 Female IV 27
Female V 15 Female V 50
J. On Anosmic Rat.
The one remaining anosmic rat was put to work upon the
problem. He learned to open the door at once, but rather
than enter the food box gratified himself by gnawing away
the wooden latch. He had apparently established the asso-
ciation by the fifth trial. His time-records are almost value-
less, however, being a measure, not primarily of the length
of time it took him to open the door of the food box and enter
but of the rime he gave himself for the demolition of the latch.
3. EflPect on Rats of Changing Position of Box and Cage.
After three black-and-white males had learned this problem,
the experimenter changed the posirion of both the control
cage and the problem box. In the original experiment the
entrance to the cage was on the east, and the door of the prob-
lem box upon the south. After the change, the door of the
cage was to the north, and the door of the problem box was
to the east. The relative positions of the entrance of the cage
to the door of the problem box thus remained the same; only
the absolute directions had been changed. The cage and the
Digilizcd by Google
A STVOr OF SEffSORr CONTROL IN THE RAT. 53
enclosed problem box had been rotated through an angle of
90°. The floor of the cage was of galvanized iron sheeting,
and was turned with the endre apparatus.
Fig. 4.
NoTB The dotted line shows the direct pathway from the entrance of the
cage to the door of the problon box. Rats which have established a regular
pathway use the one indicated in A. The dotted line in B.showsthelen^ened
pathway the rats followed after the problem box and cage had been turned.
TTiree normal black-and-white males had learned the prob-
lem. Their time-records had been reduced to .03 min., i. e.,
practically to the reaction time of the animal.
The appended diary notes describe the behavior of the
animals very clearly.
DigilizcdbyGOOgle
DiBiiizcdb, Google
A STUDY OF SENSORT CONTROL IN THE RAT. $$
The notes call attention to three characteristics of the ani-
mals' behavior under the new conditions: (i) The immediate
excursion to the south side of the box; (2) confusion at failing
to find the door; (3) nosing about to discover the door, and (4)
the discovery of it made apparently in these cases at least, on
the data atforded by either the contact of the vibrissx, or of
the snout with the latch or with the door. The door was not
held firmly in place by the latch, but wavered slightly when
an animal exerted pressure upon it with its snout or with its
claws. This yielding of the door apparently often stimulates
a general motor overflow which results in movements of vig-
orously biting and clawing at the door even before the animal
associates the door with the process of procuring food. It
is quite probable that as the rat searches for the entrance to
the box, the yielding of the door or the mobility of the latch
is the stimulus which releases the movements that raise the
latch.
There was no indication that any of the rats located the
door by means of vision, for each rat passed the door while
'searching' for it without reacting to it. Yet when the door
was touched there followed the examination of the latch, and
the performance of the requisite movements to open the door.
The next day after these tests and the second day following,
these experiments were continued, with the same general
results. When the door of the control cage was turned to the
north, the rats went first to the south, then to the east, finally
locating the door as before, — probably with the snout. Bui
each rat went frst to the south, where the door had been two
days before. The old pathway involved a turn first to the left,
then to the right, then to the right again. In the new position
each rat lengthened his path and, after making the previous
series of turns as before, added another turn to the right, arriv-
ing at the absolute spot to which his shorter path had hitherto
brought him.
A blind black-and white rat was tested in the same manner,
with the cage and box in the two positions. He exhibited the
same characteristics as the normal rats, except that in his
confusion he went over the food box, a habit that he had ac-
Digilizcd by Google
56 FLORENCE MCHASDSON.
quired in learning the problem. The habit had almost dis-
appeared, but when his first attempts were unsuccessful, he
reverted to his early random movements. His time-records with
the box in the changed position suffered no greater increase
than those of the normal rats under the same conditions.
These tests, like those involving the changed position of
the plane, were not sufficiently well controlled to justify carry-
ing them further. The animals had learned the problem with
the source of light to the west. When the apparatus was
changed, the brightness values of different parts of the field
were also changed, whereas they should have remained con-
stant. In addition to this, the control cage was not large
enough to permit the rat to go to the entrance to the door of
the problem box without brushing the corner of the box. In
this way one rat accidently discovered the latch in passing. To
control the conditions properly in such an experiment, a larger
control cage covered with canvas, and lighted from within,
would be necessary.
The above test seems to indicate the value of touch in locat-
ing the latch. The normal rats, like the blind rat, seemed to
discover the latch by contact. The functioning of anything
like discriminative vision could not be detected in the behavior
of any animal submitted to these tests. If such data had been
made use of, the fact should have been apparent in the method
of discovering the door. A rat when 'searching' for the door '
often passed it, and seemed oblivious to its location although it
was not more than three inches distant.
The behavior of the animals in this experiment justifies the
discussion of the behavior of rats in tests in which the position
of the plane was changed (Problem II, p. 38). The contention
was there advanced that there was no evidence of the percep-
tion of the plane by the rat: That the plane was not isolated
from the rest of the environment. In the test with Problem
III, there is no evidence that the latch or the door was singled
out and reacted to as an object.
lyGodQlc
J STUOr OF SENSORT CONTROL IN THE RAT.
Digilizcd by Google
FLORENCE RICHARDSOX,
a. Average Time-records for the Total Series of Trials,
The following table shows the average of the total time
consumed for the different groups of rats for a series of 15
trials. It has been necessary to make a comparison on the
basis of this number of trials since the normal white rats,
which were first tested had reached a stage of proficiency in
the solution at which their reactions were constant and habitual.
The later records of the other groups are given in the following
section.
TABLE SHOWING GROUP AVBKAGB OF THE TOTAL TIME (15 TRIALs) CONSUMED
BY NORMAL AND BY DEFBCTIVE ANIMALS IN LEARNING PROBLEM III.
Nofmal While 50 Blind. .
Black-and-Whice 18
L TIME CONSUMBD IN FIFTEEN
Normal /fbitt. Blaek-and- IFhile. Blind.
Male 1 36 Femalelll 2+ MalelV 63
Male II 69 FeinalelV ra FemalelV 2.95
Malelll 33 Female V 1.85
Male IV
Female 11
Female III
The great difference in the group averages of the normal
white and the black-and-white rat is due to the very long time-
record of the white rats at the first trial. The average of the
blind animals is high although the average of Blind Male IV
is less than that of Normal Male II and that of Normal Female
III. Unfortunately the fact that there remained buttwo black-
and-white animals renders this group practically unavailable
for purposes of comparison.
Digilizcd by Google
A STUOr OF SENSORr CONTROL IN THE RAT.
b. Average Time-records by Groups of Five Trials.
Normal fFbitt.
Individuals.
"
FEMALE
MALE 1.
MALE H.
MALE III.
MALE IV
■I.
111.
GROUP.
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-97
I 95
-81
.60
1.64
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.08
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07
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OS
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Black- and- IFbite Rat,.
FEMALE HI.
FEMALE IV.
GROUP.
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.60
.22
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fr-IO
.08
.06
.07
11-15
.06
.08
.07
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-07
OS
.06
11-25
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.OS
OS
ntuis. HAL
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m
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I- 5 I
16
S-49
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64
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it,
.76
l.IO I
37
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26
.60
■42
43
16-20
40
.18
-24
27
ii-iS
22
.18
36
'5
26-30
21
.20
21
31-J6
26
.20
1.42
29
36-40
3>
'3
46
30
There is not much to be added in comment on these tables.
They point out the fact that there is little or no difference in
the time-records of the white and the black-and-white rats> and
a very considerable difference in those of the normal and the
blind rats. No blind rat made an average for ten trials in
later trials so low as the highest group average for the normal
rats in such trials.
Digilizcd by Google
6o FLORENCE RICHARDSON.
Probably only the blind rats were given a sufficient number
of trials in this problem to render apparent a tendency towards
the dissolution of the association that has been commented on
in similar records for animals on Problems I and II. T^ree
of four of the blind rats raise their averages near the end of
the series.
c. Comparison of the Curves of the Different Groups.
The curve representing the average of the normal white
rats is, in this problem, more uniform than in either of the
preceding problems. While the first trial is high, the curve
drops very rapidly, reaching and maintaining its low level
on and after the sixth trial.
The curve of the black-and-white group is much lower at'
the first trial, and does not make such a rapid descent, though
at the fifth, sixth, seventh, and eighth trials it is lower than
that of the normal white rat. At the twelfth, thirteenth, four-
teenth, and fifteenth trials they run no more than .01 min.
apart. The third curve, that of the bUnd animals, is of a
different contour, as it drops much more gradually. At no
point in the series of 5 trials, does it reach a level near that of
either of the groups of normal rats. The curve is also quite
irregular.'
D. DISCUSSION OF CURVES SHOWING AVERAGE TIME-RECORDS
OF NORMAL AND OF DEFECTIVE RATS IN LEARNING THE MAZE.
On account of the necessity of plotting the curves shown in
this paper, on a much larger scale than that employed in
Watson's monograph, the difference between the blind and
the normal rats seems much magnified. The time-records for
the later trials on the maze rarely run below .25 min., while
those on Problem I of this work go as low as .02 min. A
curve constructed from data given by Watson's records' of
the normal, blind, and anosmic animals on the maze, plotted
' Tht comparison of these curves should be suppletnented by an examination
of the curves obtained from the records of untrained animals on this problem.
These curves are given on Plates VI and VII.
'Watson, liiV., pp.19, $g and 6z.
DigilizcdbyGOO^jle
A STUOr OF SENSORr CONTROL W THE RAT. 6l
on the scale here employed, is shown in Plate IV. Had the
curves for the records of the rats on Problem I been plotted
on the scale employed by Watson, the differences in the curves
would have practically disappeared.
The curve showing the records of the normal rats is made
up from the averages of four normal white males of one litter
about one year old. That of the blind rats is made up of the
averages of four blind males thirty-four weeks old. At no point
do the time-records of the normal rats, trial by trial, go lower
than that of the blind. At only two points on the curve do
they go as low. The fact that they were younger and probably
more active may partly account for the lower records made by
the blind rats. But a comparison of the average of the blind
animals with that of the nineteen, whose records go to make
up the norm, shows the same low record for the blind.
Watson has formulated the conclusion that rats can learn
the maze without the use of vision. The present writer has
the temerity to suggest in the face of some later results that
vision not only adds nothing of advantage, but may quite
conceivably be detrimental to the rapidity of the learning of
the maze. It has been shown that the maze may be learned
almost absolutely in terms of kinaestheric and organic impulses.
Since these impulses alone are sufficient, visual impulses might
be conceived of as adding a distraction.
TTje curve from the records of the anosmic rats is shown
upon the same plate. The curve from this group runs slightly
below that of the normal but above that of the blind. Here,
as in the case of the blind rats, it is possible that olfactory
impressions may be a stimulus to movements which in this
problem are detrimental to the learning process.
E. GENERAL CONCLUSION BASED UPON RESULTS OF ABOVE TESTS.
The experiment, the results of which will be reported next,
is one that does not require the formation of an association
such as has been required in the three foregoing experiments.
Its results, therefore, will not be considered in connection with
those just presented. A summary of facts will be attempted
here together with a discussion of their theoretical import.
Digilizcd by Google
FLORENCE KICHJEDSON.
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A STUOr OF SBNSORr CONTROL IN THE RAT. 63
The aim of the investigation has been to determine upon
what sensory impulses the rat mainly depends in forming the
var ous associations required in these problems. The func-
tion of the different sense processes will be taken up in detail.
/ Vision .^
a. Differences in Functional Value of Vision in Rats Pos-
sessing Pigmented and those Possessing Albino Eyes.
The evidence of greater importance of vision in rats pos-
sessing pigmented eyes is, upon the whole, equivocal. In
Problem I (see p. 13) the black-and-white animals made phe-
nomenally low records; not only is the average absolute time
of the group much lower than that of any other group upon
this problem, but the highest individual record of the black-
and-white groups, is considerably lower than the lowest aver-
age record of any normal rat. The curve representing the
average of the black-and-white animals is more regular, and
the individual variability is less, in this group than in any other.
Thesefacts if taken alone, would seem to indicate that the black-
and-white rats were at an advantage in Problem I. In the
same problem, however, the two white rats, which had had
previous experience in other problems, made still lower records,
(p. 103).
In Problem II there was little difference in the average
' The temi viiion up to this point has been used in the most general way. At
thit juncture it seems necessary to qualify its si|Tiificance and to indicate the
dtfTerent ways in which impulses from the eye may be rendered serviceable.
1. Possibly the most primitive funnion of such impulses is that of heighten-
ing the genera] tonicity of the motor area. This hypothetical tonic effect of
light impulses is referral to more extensively later.
2. White light vision implies that an animal's reactions may be modified in
accordance with the brightness of visual stimuli.
3. The term color-vision implies that the animal can react in a sdective
way to tight stimuli of different wave lengths.
4. Form- and- size- vis ion would be said to be present if the animal were able
to discriminate the form and size of the visual stimulus to which he reacts.
5. A further possibility is depth discrimination, which in the rat may or may
not involve retinal factors. One would infer the presence of this form if the
animal were able to react accurately to stimuli placed at varying distance inter-
vals in the line of vision, provided that one were certain that no other form of
sensory impulse were operative.
Digilizcd by Google
64 FLORENCE RICHARDSON.
absolute dme-records of these two groups (see p. 42), although
five normal white individuals made average absolute time-
records lower than the lowest individual of the black-and-white
group. The time-records of the normal white group — as
shown in series of ten trials each (p. 44) — are uniformly
lower ten by ten — than the corresponding records of the black-
and-white group, while the lowest individual records in such
a series were made by those having albino eyes. The time-
record of the white rats was lower for the first ten trials, and
the difference between that of the first and second ten was in
their favor. The curve is lower for the white rats to the 25th
trial, and from that point there is no advantage accruing to
either group.
These facts indicate that in this problem the rats with albino
eyes made slightly better records than those with pigmented eyes.
In Problem III the black-and-white rats made a much
better average absolute time-record, and their individual records
were lower. (See p. 32.) The tables giving the average abso-
lute time-records in groups of 5, show a much lower average
for the black-and-white rats in the first and second series of
five trials each, but in the third series, the white rats made not
only a lower average record, but no black-and-white individual
made so low a record as that of certain individual white rats.
In the results of experimentation reported later (p. 103) a
comparison may be made between the time-records of four
untrained white rats, and four untrained black-and-white rats
on Problem III, The untrained black-and-white animals
made a lower record for the first series of five, a higher rate
for the second and third series, a lower for the fourth and fifth,
and a higher for the sixth.' As has been shown in Part II,
' UntraineJ Unlraintd
white rat!, hlack-ani-vibiu ratt.
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6-10 60 1. 16
ins " -Bi
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Digilizcd by Google
A STVOr OF SENSOHr CONTROL IN THE RAT. 6$
rats which have had experimental experience are much more
apt in learning a new problem, presumably, largely because of
less timidity during the experimentation. The black-and-
white rats which made low records in Problem I were unusually
tame at the beginning of the work, which probably accounts
for their more rapid success. They were noticeably superior
on Problems II and III.
It must be admitted after the consideration of the above
data, that the evidence regarding the comparative functional
value of vision tn rats possessing pigmented and those which
have albino eyes is not decisive.
b. Effect of Loss of Vision.
The following discussion must, in the nature of the case,
deal with the effect of the loss of vision rather than with its
explicit function when present in the normal animal. The
entire series, as remarked above, afforded no opportunity for
determining the exclusive function of vision. The change in
conditions in the tests on Problems II and III illustrate this
point: the animals did not seem to rely upon visual, but rather
upon toctual and kinesthetic stimuli, yet the blind rats were
at a disadvantage as compared with the normal animals.
The least apparent difference between the blind and the nor-
mal white rats is in Problem I. The records of the normal rats,
as a group, are better; the absolute average time for the white
group is lower (see p. 21), although the difference between
these averages of the two groups is less than the individual
variations among the normal rats. The average of the abso-
lute time for the poorest two normal males and two females
(Males II, III and Females I and V, averaging .41 min.)
compared with that of the best two blind males and two females
(Males III, IV and Females III and V, averaging .27 min.)
proves this statement conclusively. In fact, if the poorest two
records of the nine blind rats be rejected, the average for the
remaining seven animals is .33 min., which compares most
favorably with the group average, .34 min., of the normal rats.'
* The extrandy hi^ records of the two blind animals, Malel and Female 1,
are responsible for the higher group average of the blind rau.
Digilizcd by Google
66 FLORENCE SICB^RDSON.
As regards the rate of learning, the normal rats were superior
(see p. 2i). The first two successes of the blind rats were
accomplished more quickly (see Plate I) than those of the
normal, though from the fifth trial to the end of the series
the curves representing the normal rats is, for the greater
portion of its length, below that of the blind animals.
In Problem II it may be questioned whether the blind rats
formed the necessary association for the solution. But two
animals, Females IV and V (see p. 42), so reduced their time-
records that their individual curves approach the contour of a
learning curve. The records, averaged in groups of ten,
show that there is not a sufficient reduction in the time-records
to warrant — on the basis of time consumed — the assumption
that these rats were successful in this problem. The behavior
of several of the animals at the end of the series warranted the
statement that no definite path was chosen The greater varia-
bility of the group renders its average absolute time useless
as a basis of comparison.'
A comparison of the graphs showing the average time-records
of the various groups (see Plate II) suggests the doubtful
justification of considering the curve of the blind animals as
a learning curve at all. It must be recalled here, however,
that two blind rats did arrive at the solution, though somewhat
more slowly than any normal rat.
In Problem III, likewise, there is a very considerable differ-
ence in the records of the two groups. The blind rats learned
to solve the problem, though the absolute time is higher through-
out the series, and the rate of learning much slower (see p. 59).
The individual variations as to time-records is not nearly so
evident here as among these individuals on Problem II.
The differences in the results obtained in tests with blind
animals, and with those which possess vision, var}' with the
nature of the experiment to which the two groups are sub-
jected. Watson found that vision could be dispensed with in
the learning of the maze without perceptible loss to the process.
In Problem I of this series there was but little advantage
' Compare the average record of Blind Female II for the first ten trials with
that of any other normal or defective rat.
Digitized byGOO^Ic
A STVDT OF SBNSORr CONTROL /A' THE RAT. 67
accruing to the normal animals; in Problem III there was
considerable, and in Problem II the blind animals were at a
decided disadvantage. In the face of these facts it seems
possible that the loss of vision is disadvantageous to the solution
of these problems in proportion as the problems demand
movement which, to be effective, must be definitely controlled
as to the exact locality in which it is to be put forth. In the
maze, the activity of the animal is definitely confined by the
maze itself; namely, narrow alleys which the rat must traverse.
Problem I approximates the labyrinth type in that the animal,
during the solution of the problem, is somewhat restricted in
its movements by the nature of the apparatus. Problem III
demands movements performed within a definite area, move-
ments unrestricted save by the motor tendencies of the animal.
Problem II demands a similarly specialized movement with
the added complication that the area in which the movement
must be performed Is at a distance from the food stimulus.
Assuming that the above problems represent, in the order I,
III and II a series of increasing specializations of adaptive
reactions, it would seem that the loss of vision becomes more
disadvantageous throughout the series.
The above tests are not of such a character as to afford
unequivocal evidence concerning the possible function of
vision.
The eye as previously stated affords impulses to the motor
center which are presumably tonic In character. The motor
impulses which are to result in general bodily movement are
always conditioned by the sum of tendencies operative in the
motor area. If the tonic condition of this area is low, as might
be the case in blind animals, it might well happen that the
requisite association would be slow In forming. It is possible
in this way to account for the fact that although in their behavior
these animals gave no evidence as to the function of vision
the rats that through blindness may have had an Insufficient
energy surplus of the kind called for in these coordinations
were slow in learning or failed to learn In so far as the problems
demanded well concatenated activities.
Digilizcd by Google
68 FLORENCE SICBASDSON.
2. Olfaction.
The group of anosmic rats made a higher average absolute
time-record for Problem I (see p. 21), and the rate of learning
was comparatively poor for the group as a whole. Two indi-
viduals, Males III and IV made records that were lower — in
series of ten trials each — than the average of the normal
group.* The average time for the first ten trials is particularly
low for Males II and III.' The individual variation is high.
On Problem II the time-records of the one anosmic rat are
valueless as a basis of comparison. He learned the problem,
but did not solve it as the other animals had done (see p. 34).
Problem III was also learned in an eccentric fashion, which
vitiated the time-records, although the association was well-
formed and at the rate of the normal rat (see p. 52).
In the learning of the above problem it is not necessary for
the rat to establish and follow a pathway on the basis of
olfactory impressions. Such impressions may accelerate or re-
tard the learning process; accelerate when the odor is a part of
the stimulus connected with the problem box, e. g., when the
stimulus releases movements which may result in the successful
manipulation of the apparatus, such as clawing or hiring at a
latch ; otherwise disadvantageous, resulting in the dispersal of
'attention,' as when the rat spends time in smeUing the control
cage; or, as in Problem II, in sniffing at the food, when his move-
ments to be successful, must be performed elsewhere. This is
the probable explanation of the fact that the time-records of
the anosmic rats are frequently lower than the corresponding
records of normal animals.
5. Touch.
The impulses furnished by the sense of touch seem to play
an important part in the adapution of the animal to these sev-
I Eliminating the record of the first ten trials of Male II], which was high
because of a veiy long time consumed in his first success, the average of the
group for the trials from i-io, .84 min., is much lower than that of the noimal
rats.
' Compare these records with that of the blind anosmic rat, given on p. 106.
Digilizcd by Google
A STVOr OF SENSORr CONTROL IN THE RAT. 69
eral experimental situations. A very great difficult arises
when an attempt is made to separate the functions of the
tactual from that of the kinaesthedc and organic. The tactual
impulses alone, or in the complex, are the sdmuH to the digging
movements in Problem I, and in part to the movements of
pressing down the plane in Problem II. In Problem III,
certain familiar tactual impressions are evidently the srimuli
to the discovery of the latch after the rat has arrived at the
locali^ of the door. Contact seems also to be the cue to move-
ments which result in raising of the latch, during both the
learning process and the period in which the movements are
habitual.
^. Kinasthettc and Allied Impressions.
The role of kinaestbetic impulses in the early processes of
learning probably varies in inverse proportion to the degree in
which the movements must be adapted to a definite locality.
Later in the process, as the movement becomes more or less
auu>matic, the kinesthetic and allied impulses seem to assume
first importance as the means of control. In the maze such
sensory impressions are sufficient. In Problem I no others were
indispensable to a rapid establishment of the requisite associa-
tions. In Problem III, it was evident that vision could be
profitably dispensed with in proportion as the reactions became
automatic. In Problem II these impressions resulting from
muscular activity were not only essential in the following of
the pathway, but seemed also to be of service in giving the
cue for the excursion to the door of the food box after the
plane had been successfully lowered.
F. PROBLEM IV.
/. Description of Apparatus and of Method of Teaching Rats
to Jump.
The three foregoing problems have been solved — though
with varying degrees of success by the blind rats — by means
of an evident reliance mainly upon kinesthetic and tactual
stimuli. The necessity remained to devise a problem in which
Digilizcd by Google
70 FLORENCE hicbakdson.
at Brst sight it would seem that vision must be the only, or at
least the esssential, means of control.
Dr. Carr, when working with rats on the maze, used one
rat which jumped from his hand to the t^Ble, although the
next day the rat jumped in the direction of the maze but struck
the floor. Two black-and-white rats which worked upon Prob-
lem I, in their anxie^ to get food, acquired the habit of jump-
ing from the experimenter's hand into the open door of the
cage, a distance often of six or eight inches. These observa-
tions suggested the construction of a piece of apparatus which
would necessitate jumping as a means of obtaining food. It
would seem that in such an activity vision would be essential
for successful coordination.
It is conceivable, however, that the stimulus which leads
the animals to jump from one platform to the other may come
through one or more of three pathways: (i) visual, (2)
olfactory, (3) tactual and kinesthetic. Factors i and 2 alone
would be adequate to control the direction and distance of
the first jump. Factor 3 might cause jumping to occur, but
only after some experience of consequence would it serve to
control the distance and direction of the leap. Under the con-
ditions of the experiments here considered, it was possible to
eliminate contact as a means of sensory control by keeping
the tactual conditions constant throughout all the experiments.
The attempt to eliminate the kinxsthedc factor was made by
varying irregularly the distance between the two platforms.
Smell was eliminated by the use of anosmic animals, by keeping
the apparatus clean, and by control experiments upon the
normal animals in which no food was given until after the
jump had been taken. It was thought that the role of vision,
the remaining factor, could be determined by comparing the
behavior of the normal animals with that of the blind. In
view of the fact, however, that the normal animals were so
deficient in the ability to control their movements when the
distance between the platforms was altered, the experiments
are not decisive as regards determining the nature of the role
which vision plays.
The factors involved in this coordination are so delicate
DigilizcdbyGOOgle
A sTuor OF sENsoar control in the rat. 71
and so complex that the time allotted to it was not sufficient
to answer all the questions which arose. Indeed, theexperi-
menter feels that many of the questions which are here tenta-
tively answered must be supported by a much larger group
of facts before they should have anything like scientific assent.
FIGURE 5. SHOWING THE MODIFIED
THE AFFARATUS.
The first apparatus used in this experiment consisted of two
2 inch by 2 inch wooden uprights 20 inches high, each sur-
mounted by a 5 inch by 5 inch platform of i inch board. The
uprights were attached below to a 4 foot length of 2 inch by
2 inch timber, supported by wooden legs. One of the uprights
was fixed, the other movable. The distance between the plat-
Digilizcd by Google
72 FLORENCE uchaudson.
forms' might be varied from o to 40 inches. The entire
apparatus was painted white.
The first group of rats consisted of four normal white males.
Their exact ages were unknown, but were estimated about
180 days. They had been used previously for three weeks in
tests upon the maze, and were accustomed to being handled.
Since time-records were not sought here, but information
about the delicacy of functioning of such visual-motor adjust-
ments as would be required in jumping coordinations, the age
and the training of the rats were not matters of concern.
These animals had learned to jump from the experimenter's
hand to the open door of the cage, and had accomplished these
feats at varying distances up to 12 inches. When they were
put to work upon the apparatus, they had acquired the
coordinations for short distances. These coordinations are not
common to rats held in captivity. They do make short leaps
in springing to and from the wire sides of their cages, but any
such long jumps as they had to accomplish in these tests are
entirely foreign to their usual habits. In the majority of cases
the difficulty and slowness of the training was distressing to
the experimenter, though in several instances the ease with
which the jumping coordinations were acquired was surprising.
Most of the animals were emotionally disturbed by the con-
ditions of the experiments; in three cases a fall so frightened
the animals that they refused for a time to react in later tests.
The method of teaching the rats to jump was ordinarily
laborious. The apparatus was placed in the middle of the
floor in such a position that the rats were forced to jump
toward the east. The platforms were placed at a distance of
four inches apart. The rats were coaxed across with a morsel
of food. Platform II was within reach of the animal's nose
and the step across was usually taken without hesitation.
After each successful effort the animal was allowed to eat a
trifling amount of food. When the rats had become accus-
tomed to stepping across, the distance between the platforms
was gradually Increased one inch at a time. Up to a certain
' "Oie platfonn upon which the food was placed and to which the rat jumps
will be designated as Plaiform II: the one /rom which it jumps as Platfoim I.
Digilizcd by Google
A STVOr OF SENSORr CONTROL IN THE RAT. 73
distance the rat was able to step across with little difficulty,
and contact of the snout or vibrissae with Platform II seemed
to be the essential stimulus in the majority of cases.
The difficulties began when the distance was increased undl
Platform II was out of the reach of the rat's snout or vibrissae.
Here a double complication arose: (i) The old contact stim-
ulus was lacking; and (2) there was the necessity for making
a springing movement, in which at one instant, all four feet
are without support. Several rats had no difficulty at this
point; some had great difficulty; but eventually they learned
to make the muscular adjustment required for the leap.
Three defective rats — after many hours of coaxing — utterly
failed to make the coordination. The following notes show
in detail the typical behavior of a normal rat while learning
to jump.
Diary Nolet
of Normal Whiit Rat III (FemaU) in Uarmng t
Jump.
INCHES
IMALS
1 1/30/07
ted on platform. Small, frail, but active rat.
I2/./07
4
5
All good.
S
S
All good.
6
5
All good.
12/2/07
5
5
All good.
6
S
All good.
7
5
On first trial she scrambled sli^tly;' other trials
good.
First trial, struck slightly toward north side
8
5
ofplatfoim,secondtrial,on south side of plat-
form, other trials good.
9
5
All good.
10
5
Scrambled on first trial, others perfect.
II
5
Scrambled on first trial.
12/3/07
8
Went clear over platform.
9
5
Perfect.
5
First trial a slight scramble, others perfect.
"
5
Similar behavior.
' The phrase 'scrambled slightly' is descriptive of those trials in which the
rat landed with the hind feet off the upper surface and against the side of the
platform. The word 'scrambled' indicates that the rat landed with the forefeet,
but not the hind feet on the platform, and scrambled on. If the rat could not
climb on easily, the result was noted as 'short.'
Digilizcd by Google
FLORENCE RICHARDSON.
INCHES
TRIALS.
12/4/07
Perfect.
Perfect.
Perfect.
Perfect.
Pint and fourth trials scrambled, three perfect.
Scrambled on second trial, othett perfect.
12/5/07
Perfect.
First trial landed with heels on edge, but struck
squarely.
First and second trials, scrambled slightly.
First trial short, others perfea.
11/6/07
Went clear over.
Struck squarely but with great force.
Perfect.
Perfect.
Perfect.
Krst trial scrambled, others perfect.
20
As above.
22
6
Second trial, landed south of platfotm.
Third trial, struck north of platform. In these
long jumps she landed with such force that
she was almost breathless for several seconds
afterward.
12/7/07
16
'
Would have slid off east side platform if »peri-
menter had not caught her.
18
20
'
Same procedure as above.
Again the same.
Tliis rat was not tested at distances greater than 2z inches.
Rats I and II, which were lai^er animals, had learned to make
longer jumps. Their records for trials greater than this dis-
tance are given below.
Digilizcd by Google
A STUOr OF SENSORT CONTROL IN THE RAT.
R«t II.
tNCHBS
TRIALS
8/10/07
22
,0
First and sixth trials, a little short. On other
trials he slid across platrorm' and nearly went
off.
Pint, short; third, bunh and eighth scrambled.
8/JI/07
M
10
(His foot was sore.) Second trial overshot;
fourth, to nonh side.
8/11/07
24
10
Fim,ihort; second, overshot; third and fourth,
to north side of platform; eighth, struck
squarely, buihad too much momentum and
slid off.
26
S
First, scrambled; second, slightly long; fifth
short.
28
S
Third, shon; fifth, overshot. (Foot was sore,
discontinued tests for the present.}
8/23/07
21
10
Third and sixth trials, scrambled.
10
First, short; second, scrambled; third, low.
8/24/07
26
10
Second trial, struck north side of platform;
founh, subtly short and to south; ninth,
overshot.
2«
10
Second trial, slightly long; fourth, scrambled;
othen perfect.
30
Second, fourth and sixth trials. low;rai had
not aiming at platform.
The notes mention several characteristic features of the
learning process: Tlie 'scramble' on the first trials for length-
ened distances; the over-innervation for shortened distances;
and the frequent compensations for errors, as when the rat
landed on the south side of the platform on one trial, it
struck upon the north side on the next trial.' This character-
istic is referred to in the discussion of a later test.
' The experimenter attempted to devise some means whereby an ohjective
measurement of the rat's coordination could be taken. If the records could have
been obtained of the exact point at which the fore feet first came in contact with
the plaform, a curve could be plotted showing the accuncy of the adjustment.
A cloth, marked in black and white squares i cm. in size, was carefully tacked
over the top of Platform 11. The experimenter endeavored to note the lines
Digilizcd by Google
76 FLORENCE BICHAKDSON.
2. 'Jumping in Constant Direction, t. e., A pparattts in Easl-
West Position.
I. Statement of Results. ^
a. On Normal White Rats.
The results of the tests on the four normal white rats has
been sufficiently discussed in the description of the learning
process in the foregoing paragraphs. Each rat learned to
jump the distances up to and including 22 inches. One had
jumped 28 inches with considerable accuracy: one other had
made eight perfect coordinations out of a possible ten at this
distance, and seven out of a possible ten at 30 inches.
Three other rats learned to jump. One of them, a small
male, learned to jump a distance of 22 inches in eleven days,
but was slow for several days thereafter. A second, the best
of the entire group at the first trials, learned in two days to
jump 15 inches, then began to hesitate and finally refused to
take such long distances. A third rat easily attained a dis-
tance of 12 inches, after five days training, but the later learning
process was retarded by emotional factors, the results evidently
of a fall on the third day of the tests. Eventually after five
weeks of constant training, he jumped 22 inches, but with an
average of only 50 per cent of accurate adjustments.
h. On Normal Black-and- White Rats.
Three female black-and-white rats were employed in the
experimentation. Two of them were animals which had been
used in the series of previous problems. Each did exceptionally
well, both in learning to jump, and in the accommodarion to
changed conditions of the experiment. The third rat was the
mother of the above two, an extraordinarily energetic animal,
and one without fear. Her records on this problem — the only
one she attempted — are little short of phenomenal. She was
placed on Platform I at a distance of five inches from the food
upon which the cat ahghted, but the movements were so quick, and the rat ao
i>ftai itid along by reason of his momentum, that the attf^npt was a failure.
The use of smoke] paper was likewise out of the question, as the resulting
imprint was only a large erasure of the lampblack.
.yGoool^
J STVDr OF sENsonr control in the rat.
77
platform. She stepped across at once. The distance was in-
creased to 6 inches and she did not hesitate. She jumped
sixty times within an hour on her first day with but one error;
these trials included five at 14 inches. Her complete record
is given below.
Blaek-anJ-Whiit Rat Number III.
INCHES.
ntiALS.
"/I+/07
5
5
First day. Had never been placed upon plat-
form before. Stepped across immediately.
6
10
All trials perfect; jumped across at once.
7
Perfect. The most active nit we ever knew.
8
Perfect.
9
Struck platform squarely every trid and always
jumped immediately when she was returned
to Platform i.
10
All trials perfect.
All trials perfect.
11
AH trials perfect.
'3
All trials perfect.
"*
First trial, struck left side platform, all others
squarely. Sixty trials first dayl
II/I5/07
10
Went dear over.
12
Struck and slid off east.
10
First trial, overshot; second, scrambled, others
perfect.
Good; last trial, struck and slid off.
II
5
12
First two, a little shott, others perfect.
13
As above. (Not so active. Muscular soreness
from unusual exenion of yesterday f)
II/I6/07
12
Three perfect, two scrambled.
1+
First trial, short and fell.
•5
First and second trials, a little short.
I I/I 7/07
All good.
14
IS
First trial, a little short; second, scrambled.
Same as above.
11/18/07
'♦
Four perfect.
IS
First and second a little shon.
16
Good.
17
Perfect.
tS
First trial did not strike exactly in center.
19
First trial, short and fell.
20
A little short first trial, others perfea.
As above.
22
All perfect.
II/I9/07
18
All Rood.
30
Four trials perfect.
«
Perfect.
DiBiiizcdb, Google
FLORENCE RICHARDSON.
Blatk-aad-Wbiu Rat I.
INCHES
™als.
8/25/07
8
8
Jumped almost at once but scrambled; second
and third good; fourth, seventh and eighth,
■ctamblcd; all others good.
8/27/07
8
6
All good.
9
5
Second, scrambled; all others good.
10
10
12
10
I*
10
First and tenth, shoit and fell; third scrambled;
others good.
8/28/07
8
2
Jumped entirety over both trials.
12
10
Second and eighth scrambled ; others good.
■4
6
First and third, scrambled; others good.
10
Second and third, scrambled; others good.
18
9
Third, fifth and sixth, scrambled; ninth. short
andfcll; others good. Was breadiless and
seemed tired.
8/29/07
12
2
Both jumps too long, wem over platform.
16
5
First, struck on north of platform and scram-
bled; distance good but direaion faulty;
third, scrambled; others good.
18
10
First, too far north; second, third and sixth,
scrambled sUghtly; ninth, toward north.
20
10
Fifth, scrambled slightly; others good.
8/30/07
20
10
Sixth, scrambled slightly; ninth, short; tenth,
good.
First and third, short; seventh and ninth scram-
22
10
bled.
8/31/07
20
7
Second, scrambled; fifth and seventh, shon and
fell.
First and third, scrambled slightly.
9/ '/07
18
5
20
10
First, second, seventh and ninth, scrambled.
22
10
Firs, scrambled; third, fell on south.
Blatk-anJ-fFhiu Rat II.
Would not jump.
Stepped over easily.
Hopped across.
Hopped across.
First, a little short; third, scrambled.
First, scrambled.
On seventh trial, fell olf platform in f
to jump. All other trials good.
Short and fell. Tired.
■vGoogle
A STVOr OF SENSOSr CONTROL IN THE RAT.
INCHES
nUALS.
8/28/07
10
0
Would not attempt it.
6
5
Ftry slow lit stoning. All trials good.
8
5
All good.
10
S
All good.
12
5
All good.
1+
4
First, scrambled; others good.
8/29/07
12
0
Would not attempt it. Waited I5 min.
10
0
Would not attempt it. Waited 15 min.
8
0
Would not attempt it. Waited 15 min.
5
5
Seems much afraid and needs a great deal of
coaxing.
7
S
Better; all trials good.
>4
S
Ail good.
16
5
All good.
18
5
All good.
20
2
All good.
8/30/07
16
10
Very slow. Fim trial, scrambled; tenth, short
and rell.
8/31/07
16
0
Would not attempt to jump.
>+
5
Timid. Fim, too long and fell; others good.
16
First, scrambled; fifth, fell oiT the south side
ofPIatfonnll.
18
5
First, second, third and fifth trials, scrambled.
Work with this rat was here suspended during an alteration
of the apparatus. The remainder of the learning process was
like that of the other normal rats at these distances, and is
not quoted further.
c. On Blind Rats.
The experimenter attempted to train four blind rats. The
animals were active, and one of them had had experience under
experimental conditions. The method was the same as in the
tests with the normal rats, though the procedure was muck
slower.
The rats were fed for several days upon Platform II, which
was east of and 2 inches distant from Platform I. Tlie animals
were always placed on Platform I, facing the east, and after
they had stepped across they were carefully lifted back and
set down facing the east, upon Platform I. The normal
Digilizcd by Google
FLORENCE RICHARDSON.
rats acquired their own orientation relative to Platform II;
the blind animals always adjusted themselves for the jump
in the position in which they had been set down upon the plat-
form. With these blind rats it was necessary to make the
increase by shorter gradations, one-fourth or one-half pf an
inch. Two of the rats would not attempt to cross a space
wider than they could reach with their vibrissje. The notes
on the behavior of one of these is given below, beginning with
the distance of four inches.' The notes taken on less distances
contribute nothing. The number of trials is not always given,
as they had not been counted at such short distances.
Bl-rtd Bhck-and-miU Ral on ProbUn, IF.
TRIALS
,
IO/+/07
4
.0
Stepped across to food platform, always from
the southeast comer.
4l
Stepped across many times.
5
As above.
5i
10
Was obliged to spring a little; always from the
10/5/07
5
Would not try; failure. Was obliged to lessen
distance.
4i
4
Stepped across three times after much coaxing
by holding food in front of him.
10/6/07
'
After thirty minutes he stepped across on his
own initative from thesouth-east. Could not
be coaxed across. Time, forty-five minutes.
10/7/07
♦i
10
Stepped across from southeast comer.
s
Failure. Will only reach or spring as far as
vibrissas can touch.
TTie procedure as noted above was repeated for several days
with little variation and no satisfactory results.^
A blind rat which also had had previous experience was
' This rat had successfully solved the previous problems.
' This rat would not allow his fore feet to leave the platform unless his vibrissa
object. When the platform was beyond the reach of
er touched their tips with a pencil, whereupon he put
T. He never raised his hind feet unril his fore feet
he could always be induced to makean attempt
:. A deodorized glass rod was used instead of the
1 effect, showing that it was contact alone, and not
to make the effort.
reported
his vibrissa the experime
out his fore feet to step 0
had a tirm footing, bu
by stimulating his vibri)
pencil and it had the sa
olfaction that tempted hi
DigilizcdbyGOO^Ic
A STUOr OF SENSORr CONTROL IN THE RAT. 8 1
labored with for many days, with not so good results.* He
would not step across when the platform was within reach of
his nose. He was a slow rat at best and achieved no credit
for himself in the previous experiments.
Blind Rats III and IV (white untrained females) achieved
signal success in this test. Both learned eventually to jump
distances of eleven inches, and Rat III successfully cleared
fifteen inches. A portion of the notes on the behavior of this
rat is given here as they are of particular interest.
INCHES
TRIALS
II/I9/00
B^an the experimentation with the platfonns
two inches apan. Coaxed her across with a
morsel of food. She used vibrissa to locate
the platfonn. Distance gradually lengthened
to four inches. This was the daily program
for ten days.
11/29/07
+i
10
Stepped across. An aaive rat.
5
5
Hopped across. (Had never been able to get a
blind rat to 'hop' before.)
s»
5
Hopped across. Never turns around. (When
returning blind rats to Platfonn I ihey were
always placed with head toward food platform.
They rarely altered this position.)
6
5
11/30/07
*i
Would not hop across; obliged 10 reduce distance
to four inches and increased one-half inch at
a time. Would not cross after five inches.
I2/I/07
4i
Good.
5
5
Stepped across at five inches. Very slow.
5i
5
Hopped after stretching across.
6)
5
Sprang across.
71
5
Good.
Si
5
First trial, heels on an^e, others perfect.
9*
5
Same procedure as above.
10*
111
5
First trial, scrambled slightly.
Getting tired and slow. Scrambled in twu
trials and in fourth trial did not aim right;
struck wall at northeast; fell hard but ii did
not frighten her. Commenced eating at once
when placed on food platform.
' This rat was Male I whose records 1
n the average of the groups.
I Problems n and III were disr^arded
Digilizcd by Google
FLORENCE RICHARDSON.
INCHES
TRIALS.
12/3/07
5i
Would not hop across and could not step across.
5
Would not step across.
*
Stepped across.
5
As above.
5*
4
Coaxed across first trial. Hopped across in
other trials.
61
2
Went entirely over and strucL wall.
7i
4
Went over platform and fell first trial, second,
the same, third, went to east side, and just
saved herself from falling. Founh trial,
perfea.
81
5
All perfect.
(For four days succeeding above there was
the same procedure every day. At the
banning of each daily experiment, experi-
menter was obliged to reduce distance to four
inches; the animals seemed to carry over
nothing of advantage from one day's experi-
ence to the next. Each day learned anew to
12/7/07
7
^
Loitered about for a long time then jumped
nearly across platform.
9
2
First trial, perfea. Second, off at nonh.
Perfea.
13
+
Firsttrial, scrambled up overedge. Second,fell.
'S
4
Did not strike the platfotm squarely.
Scrambled each time on to the platform.
12/8/07
7
10
Jumped over platform to wall of canvass con-
trol cage. Does not jump to platform but
jumps aimlessly. Eighth and ninth trials,
struck wall at distance of twenty seven inches.
I a/9/07
Jumped across to wall six times; distance
twenty inches. Changed distance of plat-
form but would not jump toward it. After
dozens of trials the experimenter gave up in
despair.
Rat IV had learned to strike the ptatTorm squarely at a
distance of eleven inches. At this stage of her training she
discovered that she could crawl down the standard. Sharp ■
points were placed about the edge of the platform to prevent
her descent, whereupwn she jumped directly to the floor below.
Further experimentation was futile.
DigilizcdbyGOdgle
A STUDY OF SENSOSr CONTROL IN THE RAT. 8j
d. On Anosmic Rats.
To determine accurately that vision and not olfaction fur-
nished the sensory control of the adjustment, two anosmic rats
were tested upon the apparatus.*
The method of training of this animal was the same as that
with the blind rats — the distance being increased by half an
inch at a time. The following are extracts from the notts
taken on his behavior:
Anotmie Rat I on Protiem If.
INCHES
13/3/07
5
Steps across many rimes but awLward and afraid.
"
Has to be coaxed across; slow and evidently much
disturbed by fear.
-.i
An entire failure after thirty minutes of coaxing.
12/13/07
progress. Wasstiff with fright muchofthetimc when
urged to take a distance greater than he could step
across. For several days he has been gnawing fiercely
at the sides of Platfonn 1 and has rounded off the
edges and corners.
Ia/14/07
Failurel
A second anosmic rat was procured for the test. He was
hurried through the series with a fewer number of trials at
each distance because of the experimenter's apprehension con-
cerning the length of his tenure of life. He was in excellent
physical condition but had he died there would have been no
possibility of procuring another anosmic rat in time for the
experiment. On the first day he succeeded in convincing the
experimenter that the olfacK>Ty stimulus was not the essential
factor in the jumping reaction. The notes quoted below give
the detaib of his record.
*The fit^ animal was the one which had formed the associations involved
in Problems I, II and III, though his time records in the last two problems were
practically of no value becauseof the time he wasted in gnawing the apparatus.
Digilizcd by Google
FLORENCE RICHARDSON.
Anosmic kat 11 on PrtMm IV.
INCHES
™,.L.,
n/6/07
51
Fira time upon platfonn. Stepped across tm-
Jumped readily to Platfonn 11.
Perfect. No hesitation.
First trial, »crambledi othere perfect.
lU
Exact repetition of previous trial.
Same as above.
'3
Scrambled, tired. (All of the above trials within
"1/7/07
Jumped across.
Perfect.
II
First trial, scrambled; othen perfect.
13
Third trial, scrambled a little.
15
First- trial, scrambled; others perfect.
\%hi°i
Did not jump readily at first, finally coaxed
across. Struck squarely.
Perfect.
II
13
Perfect.
IS
Shoit, and fell twice; afraid, put him up.
u/u/07
6
Would not jump at first.
%
Same as above.
H
First and second trials, sctambled; other trials
perfect.
'S
As above. (!■ '^me in left hind 1^.)
ia/is/07
16
Slow. Firsttrial,struclconsouthside. Second,
same but nearer center.
18
First and third trials, scrambled sli^tly.
10
Second trial, Struck platform, but f^l off.
11
Fourth trial, scrambled ; sixth, little short and fell.
Tired.
The behavior of this rat in the above test was in every respect
like that of the normal animals. He had had previous experi-
ence on Problem I, and was apparently undisturbed emotion-
ally by the conditions of the experiment. He learned to jump
his maximum distance in a shorter time than did any other
white rat, though to what extent his facility was due to fear-
lessness and to the fact that the experimenter lost no time in
lengthening his distances cannot be estimated.
Digi-izcclbyGOO^l
A
A STUOr OF SENSORr CONTROL IN THE RJT. 85
it. Summary.
1. Five normal white rats, the three normal black-and-
white rats, and one anosmic animal were able to learn to
jump successfully a distance of at least 22 inches. Tliese
adjustments were acquired with comparative ease. One other
normal white rat learned to jump as long a distance as 22
inches with difficulty, and another did not learn to jump
more than 15 inches. No normal rat failed «> learn to jump.
Two of the blind rats (III and IV) achieved success in this test.
Both learned to jump a distance of 1 1 inches. One (Rat III)
learned to jump a disunce of 15 inches. Here the coordina-
tion broke down apparently on account of the fact that a large
percentageof her jumps were inaccurate; she had to scramble
onto the platform much of the time, and she often failed utterly
to strike it and consequently fell. Rat IV learned to jump
a distance of 11 inches, but the coordination broke down
upon her discovery diat she could crawl down the standard.
2. One anosmic and two bUnd rats were utter failures.
Two were willing tt> step across to the second platform, but
they were either unable, or else refused, to jump. The fail-
ure of the anosmic rat was probably due to the fright occa-
sioned by the unusualness of the conditions of the experi-
ment and not to any lack of proper sensory control. Under
any other circumstances he ran about naturally in search of
food. The blind animals did not seem to be emotionally
disturbed, and hence their failure was probably referable to a
bck of adequate stimulus.
3. Effect of Changing Direction in which Jump Must be
Taken.
In order to determine more accurately the sensory factors
involved in the coordinaton it was decided to change the
position of the apparatus and thereby the direction in which the
animal has to jump. It would seem that if the rats can accom-
modate at once to changes in the direction of Platform II, some
distance receptor must be operative. Such a test might also
show the possible presence of some 'directional' factor which
DigilizcdbyGOdgle
86 FLORENCE RICHARDSON.
is not visual in character. Three white rats had been trained
to jump distances gradually increasing from 6 to 30 inches.
These longer distances, as has been noted, were too great to
permit of accurate adjustment on the part of the rat, and they
demanded an unnecessary expenditure of energy. Accordingly,
a record of 80 per cent of perfect coordinations at 22 inches
was chosen as a standard of efficiency to be attained before
the animals should be tested with the apparatus turned in
another direcdon. Three white rats had reached this d^ree
of capability.
Tlie apparatus was then so adjusted that the rat must jump
22 inches to the south for food. To the surprise of the observ-
ers, two of the rats continued to jump toward the east for
twenty successive trials each. The third rat jumped twice
toward the south, though he did not jump far enough to land
on the platform; at the third trial he settled down comfortably
on the starting platform and refused to jump.
Acting on the possibility that the two rats were jumping
toward their cages — which were to the east — or reacting to
other features in the environment of a visual or olfactory
character, the conditions of the experiment were radically
changed.
A cabinet 4 feet by 4 feet, by 6 feet was built. The frame-
work was of 2 by 4 inch timber, the sides and top of white
canvas. The cabinet was illuminated by a 32 c.p. electric
light fastened to the center of the top of the cabinet. The
visual and olfactory conditions of the environment were thus
rendered subject to control. At this time the apparatus itself
was improved. The connecting rod was made of i inch pipe,
clamped in iron end supports. Tlie uprights supporting the
platforms were of ) inch steel, clamped at right angles to the
base. One of the uprights consisted of two "18 inch steel bars
clamped together so that the height of platform it bore
might be varied from 18 to 30 inches. The apparatus in this
form was much more easily adjusted to horizontal changes in
distance. It also possessed the added advantage of offering
any possible adjustment in height.
While working with the wooden platform the feet of the
Digilizcd by Google
A STVOr OF SENSORT CONTROL IN THE RAT. 87
animal became sore. In making such leaps as are necessary
in these tests — covering sometimes a distance of 24 inches —
the rat lands heavily upon the forefeet. This might have been
the cause of the soreness. The platforms were later covered
with cork matting, and this in turn with soft leather. The
whole was then painted light gray. Though the paint added
somewhat to the resistance of the surface the rats had little
difficulty thereafter with soreness of the feet.
After the cabinet had been constructed, the rats which had
learned to jump on the old apparatus were tested in the new
one. There had been an interval of three weeks since their
last trials and several days' training was necessary to bring
them up to their former standard of accomplishment. White
training the rats the experimenter remained within the cabinet
to catch them when they fell and to feed them immediately
after they reached the platform. After the habit had been
reestablished and it was desired to test the animal with the
apparatus in a new position, the rat was observed from without
through a slit in the canvas. The position of the observer
outside the cage was also changed in every test, in order that
the rat might not associate the sound of the experimenter's
movements with the direction in which the jump must be
taken.
The possibility of an olfactory stimulus was here minimized
by allowing no food in the cabinet. The rat was fed from the
experimenter's hand after the jump, and Platform II was
kept clean, and newly covered, top and sides, with black-and-
white checkered cloth — to add greater character to the visual
stimulus.
Each day before the apparatus was turned the rat was given
five or more tests in jumping toward the east which during
the previous training had been the constant direcrion. If
80 per cent of the trials were perfect, the cabinet and appa-
ratus were rotated. This change necessitated jumping to the
south, the north, or the west, as the, alteration might demand,
in order to reach Platform II. Care was taken to place the
rat on Platform I in different p>ositions during the various
trials, so that the initial position would be no cue to the essen-
tial orientation.
Digilizcd by Google
88 FLORENCE RICHARDSON,
i. Statement of Results,
a. On Normal White Rats.
The records of the normal white rats in this test are given
below.
WbiU Female I.
POSITION OF
PLATFORM 11.
12/9/07
Ean 22 in.
Ten trials, 80 per cent perfect.
South.
Perfect.
West.
Refused to jump.
Noith.
Refused to jump.
West.
Jumped south.
East.
Refused to jump.
12/10/07
East.
Eight trials, all good.
Nonh.
Went enrirdjF over platfonn to nordi, and struck
canvas.
West.
Refused to jump.
South.
Fell off platform in preparing to jump toward
south, and was frightened. No other tests
today.
I 2/1 1/07
East.
Five trials, perfea.
West.
Perfect.
South.
Jumped east.
Nonh.
Perf«t.
West.
Jumped south.
12/12/07
North.'
Jumped east.
We«.
Jumped south.
U/13/07
South.
Jumped east.
12/14/07
South.
Jumped east.
North.
Slow and confused. Will not jump.
ll/lS/07
12/16/07
West.
East.
Same as above.
' Platfonn 11 was not placed at the cast for the first trial, as the animal
exhibited a tendency to jump east habitually, and it was feared that this position
might unduly emphasize the tendency.
Digilizcd by Google
a STVor OF sensort control in the rat. 89
H'hiU Male II.
POSITION or
PLATTORM II-
12/6/07
Ea«24in.
Ten trials, 80 per cent perfect.
South, 22 in.
One trial, immediate and perfect accommoda-
W«, 24 in.
One trial, perfect, jumped at once.
Nonh, 24 m.
Direction perfect, but jumped too short.
Ean, 24 in.
One trial, perfect.
Apparatus turned but not cabinet.
Noith, 24 in.
One trial, perfect.
Nonh, 24 in.
One trial, perfect.
East, 24 in.
One trial, went sli^tly to rig^t of platform,
grazing the side.
West, 24 in.
One trial, perfect.
la/7/07
East, 24 in.
Tentrials, and but 30 per cent perfect. Jumped
down toward bottom of apparatus. EKd
not try to jump to platform.
Wbiu Male III.
Five trials,scnunbled slightly each time. Animal
is ill and weak.
Ofie trial, right direction but short.
One trial, same as above. Did not work again
and died soon after.
Two of the three rats jumped to the platform in the new
position at every test on the first trial. The third rat, Female
I, jumped to the platform which was toward the south on the
first trial, but on the second, third, and fifth trials she refused
to jump. On the fourth she jumped south again when she
should have jumped east. On the first trial for the second day
widi platform north she jumped to it at once, then refused to
jump the next time. On the first trial on the third day the
adjustments were perfect, though on two of the later trials
she jumped in the wrong direction. On the fourth, fifth and
sixth days she made no perfect coordinations, either jumping
n> the east, with one exception, or refusing to jump at all.
The tests had to be discontinued because of her disinclination
to leave Platform I. She would jump toward the east with
Digilizcd by Google
90 FLORENCE BlCHdRDSON.
the platform in that direction but not otherwise. In the case
of Rat II, also, there was a tendency for the coordination to
break down under the changed conditions, as this rat took to
jumping toward the base of the opposite standard, and could
not thereafter be induced to jump to the platform. This series
was necessarily abbreviated on that account.
b. On Normal Blact-and-White Rats.
Three black-and-white rats were given the same test. They
had attained the necessary standard of efficiency, i. e., 80
per cent of perfect coordinations at 22 inches. The following
are from the notes taken on this series.
Black-and-Wbilf Female I.
POSITION OF
rLATTOHM II.
10/19/07
East, 22 in.
Five trials; 100 per cent perfect.
South.
One trial, perfect.
W«t.
Jumped southeast five time* in succession
apparently at a shadow caused by the joining
of thecanvas strips.
10/30/07
Ea«.
Six trials, 80 per cent perfeCT. Shows tendency
to jump toward northeast.
South.
Two trials, first, slightly to east of south.
Second, perfea.
West.
Two trials, first; slightly to south of west ; second
perfect.
South.
One (rial, jumped to wall on south.
Ban.
Two trials, first, jumped to south; second to east.
Wett.
Two trials, first, southwest; second, perfea.
North.
Refused to jump.
I 1/1/07
Eatt.
One trial, perfect.
North.
Jumped northeast to canvas.
Same relative direction.
West.
Jumped southeast.
Jumped northeast to canvas.
North.
Il/s/07
South.
repeatedly hut not to platfonn. Testsdiscon-
DiBiiizcdb, Google
A STVDY OF SESSORr CONTROL tN THE RAT.
Blaek-anJ-lfbiU FtmaU II.
POSITION or
FLATToml II.
1 1/30/07
East.
Five trials, 60 per cent perfect, others good.
South.
One trial, perfea.
Nonh.
One trial, perfect.
South.
One trial, perfect.
>o/3>/o7
E»t.
One trial, perfect.
South.
One trial, perfect.
Wat.
One trial, perfect.
North.
One trial, perfect.
West.
One trial, perfect.
North.
One trial, perfect.
"1/1/07
East.
One trial, perfect.
West.
One trial, perfect.
South.
One trial, perfect.
North.
One trial, perfect.
TtniNBDAPPARA-niS BUT NOT CABINET.
I 1/2/07
South.
One trial, (Jireaion perfea but distance shon.
West.
One trial, rat confused. Put back.
' 1/3/07
East.
One trial, direction correct, distance short.
North.
One trial, perfect.
West.
One trial, perfect.
South.
One trial, perfect.
Blaek-ani-Wbiu Female III.
II/I9/07
East, 23 in.
Ten trials, 80 per cent perfect.
South.
One trial, good.
West.
One trial, good.
Nonh.
One trial, good.
East.
Eight trials, 75 per cent perfect.
North.
One trial, perfect.
South.
One trial, perfect.
West.
One trial, jumped to floor.
11/21/07
Very active rat; gets innervation before muscu-
dom leaps.
11/24/07
Will jump only to floor. Tried several de\ice8
to prevent this, but none successful. Series
discontinued.
The black-and-white rats, like the white ones, reached a
point in the tests where the accommodation to the distance and
the direction broke down completely, though it did not break
Digilizcd by Google
92 FLORENCE KICHJKDSON.
down SO soon. These rats had not been at work at the test
as long as the white animals which had been trained upon the
old apparatus and retrained upon the new.
c. On Anosmic Rat.
The anosmic rat had just reached the necessary maximum
of 22 inches before the test with apparatus rotated could be
made. He had been given two trials with the apparatus changed.
Through some mishap on the part of the laboratory attendant
the rat gained his liberty, and was not seen thereafter. His
records for the two trials follow:
R,
,GrJ „l Ammi,
Ra: P
milion of Apparatus Fariable.
POSITION OF
PLATFORM 11.
T,U.S
"A5/"7
South.
7
1
Founh trial, scrambled ; sixth, shon and
fell. Seems tired.
Slow, but accurate.
Good. Very slow.
1. Four of thejsix rats were able to direct their jumps
equally well, regardless of the direction in which the jump
must be taken. The other two animals were able to accom-
plish this in about 50 per cent of their trials.
2. These two other rats were by no means failures on the
problem. One of them. White Female I, jumped to Platform
n which was south at the first trial. She had always previ-
ously jumped to the east. After this trial she often refused
to make the effort. Of the twelve trials in which she made an
effort, she was five times successful in the direction of her
jump, and failed seven times. Of these seven failures, four
were jumps to the east and three to the south.
The remaining rat, Blaclc-and-White Female I, did not
attempt to jump toward Platform H when it was turned to
the south, but jumped five times in succession to a point in
Digilizcd by Google
A STVOr OF SENSORT CONTROL IN THE RAT. 93
the wall of the cabinet where one width of canvas overlapped
another, and wriggled through, emerging on the outside of
the cabinet. On the following day she jumped in the direction
of Platfoim II, five trials, though she did not always strilce it
squarely on the first trial, then missed by jumping south when
she should have jumped east. Soon after she failed to make
any attempt to jump to Platform II, but jumped to the walls
instead.
^ Effect of Altering Distances Between Platforms,
a. Effect of Altering Horizontal Distance.
During the training period it became evident that the rats
were unable to accommodate with any degree of ease to a
distance which was shorter than the one for which they had
established a habit. It will be remembered that the rats had
to start any given day's work with a jump which was slightly
shorter than the maximum jump which they had been able
to attain the day before. Under such conditions the animals
would often over-innervate for the first few trials and jump
entirely over Platform II.
A series of tests was undertaken to determine (i) the num-
ber of trials necessary for and (2) the sensory factors involved
in a readjustment to shortened distances. The experiments
are not so numerous as had been planned by reason of the
fact that the coordination had broken down in many of the
animals. The preceding section shows that changing the direc-
tion in which the jump must be taken tended to disintegrate
the coordination with all the animals but one. If this had
been predictable, the present experiments would have preceded
those of the last section.
The tests here reported upon were made in the cabinet
under conditions closely similar to those reported in the last
section. The food, however, consisting of sunflower seed, was
placed in a small receptacle which hung from the far edge of
Platform 11. It afforded no visual and probably little olfac-
tory stimulation.
Digilizcd by Google
94 FLORENCE RICHARDSON.
Before decreasing the distance between the platforms the
now thoroughly experienced animals were allowed to establish
a habit for the distance of twenty-two inches. The distance
was then shortened and the effort of the animal to accommodate
to it was recorded. The notes below show the changes made
and the essential features of the animal's behavior.
t. Statement of Results.
a. On Normal White and on Normal Black-and-White Rats.
The results on the white and on the black-and-white rats
are given together, since the numbers are too small to justify
a separation. Only three animals could be used for the pur-
poses of the test. The notes on the behavior of Female III
are given below.
^bite FtmoU III.
INCHES.
TRIAL..
11/31/07
11
First and second, to left of center of platform;
third, founh and fifth, good.
I/I/08
16
First, long, went over platform; second, struck
but slid off far edge; third and fourth, good;
fifth, perfect, struck squarely.
8
First, entirely over and struck opposite wall of
cabinet;i:econd,third and fourth, shoner but
entirely over; fifth, like first; siicth, seventh
and ughth, entirely over.
1/1/08
22
First short, about one-half of distance to plat-
fonn ; other four trials Rood.
8
First, second, third and fourth, long; fifth,
struck platform in passing but slid off.
1/3/08
11
First trial, short; second, landed on the right
side of the platform; fourth, scrambled ; fifth,
good.
16
First, struck platform in passing over; second,
struck S(]uardy;third and fourth, scrambled;
fifth, good.
8
Went entirety over at first trial and refused to
jump again.
■/4/08
"
°
Failure — refused to jump.
DiBiiizcdb, Google
A STVDT OF SBNSORr CONTROL IN THE RAT. 95
WhiU MaU I.
INCHES.
TRIALS
8/2+/07
11
4
All perfect.
11
10
Fim trial, second and third, entirely over;
founh, his hind feet and tail grazed plat-
form as he went over; fifth and sixth, over,
but shorter and struck platfonn with his tail;
seventh and eighth.grazed, platform widi all
fours as he went over; ninth, struck plat-
form on far sideand slipped off; tenth, landed
on further side of platform but stayed on.
8/15/07
11
°
Rat refused to jump; was evidently not well.
The animal had a sore foot and the tests were
discontinued. It died soon after.
BIack-and-^^'hite Female III was experimented with and
her records follow.
Black-ani-lfhiU FemaJe III.
INCHES.
THIAL8.
10/14/07
11
5
Fim trial, scrambled; other four trials per-
fect.
16
5
Jumped entirely over platform at every trial.
10/15/07
11
0
Refused to jump.
16
0
Refuged to jump.
8
11
Went over platform at every trial; seemed
to be jumping about 11 inches.
1 1/4/07
21
5
All good.
8
All much too long.
16
10
First trial, shorter than 11 inches but entirely
over platfonn; second, shorter than first;
third, feet grazed plane as she went over;
fourth, same; fifth, struck but slid off;
sixth, good; seventh and eighth, like fifth;
ninth and tenth, good.
b. Effect of Altering both Horizontal and Vertical Distances.
Up to this time the platforms had been at the same height,
so that the main direction of the necessary jump was horizontal.
The apparatus was now adjusted so that Platform II was 6
inches higher than, and at a distance of i6 inches from Plat-
form II. Several rats were tested under this condition, but
Digilizcd by Google
96 FLOREffCE RICHARDSON.
the upward spring seemed almost impossible of acquisition
and no rat was successful. The attempt to jump upward was
unmistakably made, with the result that the animal sometimes
struck with considerable force against the standard or the under
side of the platform, or else landed on the wall opposite or
upon the floor. No long continued effort was made to train
the few remaining jumpers lest the repeated errors should ren-
der them unfit for further experimentation.
The apparatus was then re-adjusted so that Platform II was
10 inches below the level of and 16 inches distant horizontally
from Platform I.
I. Statement of Results,
a. On Normal White, and on Normal Black-and-White Rats.
The notes on the behavior of the two remaining animals
follow.
»'hiu F*m<Ae III.
INCHES.
TRIALS.
1/6/08
Tl
•>
All good.
f 16 Horizontal
\ioVenicat
s
Was slow in preparing to jump; seemed
ready to spring several times before
she finally essayed it. Lool:ed down-
ward toward the platforni. First,
landed on left margin of platfonn;
second, third, fouith and fifth, good.
1/7/08
/16H.
\.oV.
5
Same slow and elaborate preparations
asyesterday. First and second, per-
fect; third, scrambled sli^tly; fourth
and fifth, perfect.
f 8H.
\ioV.
5
Slow in starting. Jumped downward
but considerably over the platform.
Did not seem at any trial to shorten
her jumps from those of yesterday.
All trials a failure.
i/«/o8
8H.
loV.
S
Behavior as before, only slower. No
1/9/08
8H.
2
After long intervals she jumped twice
\ioV.
discouraged she settled down for an
hour and refused to make any efforts.
1/10/08
f8H.
\ioV.
0
Would make no effort.
Di,ilizcdb,GOOglf
A STUOr OF SENSOXr CONTROL IN THE RAT. 97
Black-and-Wbilt Female II.
INCHES.
TRIALS.
■/5/07
11 H.
5
All trials perfect.
liiH.
l,oV.
5
Jumped down and struct plaifom
(quarefy.but angle was so great that
she slipped offjsecond.struck squarely
and slid but did not fall ofFj third.
founb and fifth, perfect and with less
Totce.
(16H.
lioV.
10
First, entirdy over; second, struck plat-
form with hind legs and tail as she
passed; third, shorter but still over;
fourth, fifth and sixth, landed but slid
off by reason of momentum; seventh.
eighth, ninth and tenth, struck squardy
on platform and did not slide.
1/6/07
) 16 H.
6
First, struck platform with hind feet only;
'; 10 V.
others good.
/ 8H.
\ioV.
10
First and second, over; third, over but
struck in passing; fourth, shorter;
other six trials entirely over.
■/7/"7
1 8H.
20
1/8/07
18 H.
l.oV.
8
As yesterday; all trials nere failures.
The platform was then moved out to the
point which would intersect her leap.
The distance proved to be 15 inches.
(.5H.
6
First, struck platform with tail; second,
1,0 V.
struck platform on right side and fell
ofi^; third, struck on right side but
stayed on; fouith, jump a little long
but stayed on platform; fifth, struck
it and fell off; sixth, good.
it. Summary.
I. No rat was able tx> make the adjustment when the dis-
tance was changed from 22 inches to 8 inches in a rea-
sonable number of trials. One rat failed after seventy
trials. All animals were able to adjust without great Ji^culty
CO the change from 22 to 16 inches apparently by means of a
trial and error method. An average of about one trial was
necessary in order to effect this readjustment. \\'hen the dis-
Digilizcd by Google
98 FLORENCE RICHJRDSO.\.
tance was shortened the animals always jumped too far on the
first trials.
2. In the few cases where the distance was suddenly
lengthened the jump was usually too short on the first trials.
It was impossible to compare the ease of the readjustment to
the lengthened distances, with that for the shortened distances,
by reason of the fact that the animals were taught to jump
long distances by gradually increasing the distance between
the platforms. The adjustment to an increased distance was
thus more habitual than that to a shortened distance.
3. The animals were able to adjust successfully at once for
the lowered position at 16 inches. They could adjust for a
lowered and shortened distance more easily than for merely
the shortened distance. They could not> however, adjust to
the lowered and shortened position at 8 inches. It was evident
that they were making the effort but they invariably jumped
out too far.
5. CONCLUSIONS.
The purpose of the foregoing tests was to estimate the
importance of vision in the coordination required in jumping.
Three aspects of the coordination as a whole were considered :
a Learning to jump a given distance when the direction of
the jump was constant; b the effect, after the jump under
constant conditions had become automatized, of changing the
distance of the jump, the direction remaining constant as
before; and c the effect of changing the distance and the direc-
tion of the jump in either the horizontal or vertical planes, or
in both. The data gathered from the various experiments
seem to justify the following general conclusions, stated in the
order of the problems as indicated above.
a. Learning to Jump — Direction Constant.
The results indicate that the loss of vision in some way
interferes with learning to jump long distances and greatly
decreases the ease and rapidity in the acquisition of the coor-
dination for short distances. In the case of the two blind
DigilizcdbyGOOgle
.* STUDr OF SENSORr CONTROL IN THE RAT. 99
individuals which failed, it seemed that some element was
lacking which was essential to the initiation of the act. The
fact that two blind rats learned to jump even the shorter dis-
tances, and that the normal animals had to accommodate by
a trial and error method to sudden increases and decreases in
the distance between platforms, indicates that up to a certain
point, other than visual factors are concerned in these adaptations
to a distant stimulus. The blind animals, unUke the normal
animals, did not move about when placed facing the east on
Platform I: they were given their orientation and retained it.
The normal animals moved about on the platform so continu-
ously that the experimenter made no effort to put them down
in a relatively constant position. The fact that their orientation
was given to the blind rats was probably the reason of their
success. An attempt was to have been made to test this factor
by changing the initial position, but the coordination disin-
tegrated before the test could be made. Certainly the experi-
ments on the process of learning to jump are not decisive in
indicating what role vision plays in this coordination.
It has been shown that the tactual, kiniesthetic and olfactory
senses are able to mediate accurate adjustments to short dis-
tances even in the absence of visual impulses. The separate
role played by each of these senses in the case of the blind
animals has not been determined. Judging from the tests
upon the anosmic animals it would appear that olfactory stimuli
can be dispensed with both during the acquisition of the habit
and at all later times. Touch, as a partially controlling factor,
does, however, enter into the early adjustments of the blind
animals, since they will more readily form the habit of jumping
if the snout or vibrissa are stimulated by the platform to which
the animal has to jump. This latter statement applies in some
degree at least even to the animals possessing vision. Once
the habit is formed, however, the initial tactual impulses can
be dispensed with.
In regard to the function of kinesthetic impulses in the case
of the blind animals, it seems safe to affirm that they soon
come to usurp whatever function tactual impulses from the
snout and vibnssx exert in the learning process. TTiey soon
Digilizcd by Google
lOO FLORENCE RICHAIIDSON.
become the only indispensable means of control in the blind
animal for such short jumps as they were able to accomplish.'
b. Effect of Lengthening or Shortening the Jump, Direction
Constant.
From the experiments on p. 93 it follows that the change
in visual impulses conditioned by lengthening or shortening
the distance between the platforms is not adequate to effect
the change in innervation necessary for a successful coordina-
tion. Lengthening or shortening the distance between the
platforms may bring about a change in accommodation and
in convergence (kinesthetic factors) and certainly occasions a
change in the intensity of the visual impulses and the size of
the area of the retinal elements which receive the stimulation
(change in visual impulse proper). In the case of these types
of animals, monkey, cat, etc., where adjustments under similar
conditions are accurate, the above noted changes in the sen-
sory complex in all probability are sufficient to bring about the
proper modification in the motor discharge. In the case of
the rat, however, these delicate changes in sensory stimulation
are inadequate to modify the habitual motorresponse. The rat
apparently, in order to accommodate to the changes in distance,
must make trial movements, that is, must establish a habit of
jumping a given distance. Any change in the distance calls
for learning factors similar to those already discussed on p.
72. It is evident that by means of these trial jumps the animal
is bringing into play the large muscles of the body (as contrasted
with the eye muscles and the ciliaiy muscle) and is thereby
gaining a control over the motor area which it is perhaps impos'
sihle to obtain by the visual changes and the changes involved
in accommodation and tn convergence. These facts in them-
selves are suggestive of the relatively secondary importance of
vision in the life of this animal.
It is thus seen that the attempt to eUminate the function of
kinjesthetic impulses by irregularly changing the distance has
'The tenn kinaesthetic as here employed necessarily includes whatever
impulses come rrom the skin of the feet. These impulses ate presumably
fused with those from the muscles.
DigilizcdbyGOOgle
A STUOr OF SENSOXr CONTROL IN THE RAT. 101
not been successful in isolating the role of vision, by reason of
the fact that when the distance is altered the habit breaks
down and readjustment must take place. Had the animals
been able to accommodate to the changed conditions without
trial movements, the conclusion that the visual complex (visual
impulse, accommodation and convergence) was the essential
sensory factor involved in this coordination would be justified.
But since trial movements are necessary, the problem remains
as to whether kinxsthedc impulses alone are responsible for it.
c. Effect of Changing Direction of Jump.
The experiments summarized on p. 92 and p. 98 were much
more successful in giving evidence of the function of a distance
receptor. Since the possibility of the use of olfaction as a
sensory control had been practically eliminated by previous
exfteriment by precautionary methods above described, and
since audition could not have furnished such guidance, it is
evident that vision or some other undetermined receptor, func-
tioned here in such a way as successfully to control the adjust-
ment to a distant stimulus. Assuming for argument that
vision is the effective source of control, it may be maintained
that the visual impulse seems to afford evidence concerning
the direction of the stimulus but is apparently not alone capable
of controlling the amount of innervation necessary to make
the requisite adjustments. In other words, visual impulses in
such a form as may be designated white light vision are opera-
tive' and afford a basis for controlling the direction of the
adjustments, but do not operate so as to furnish informadon
concerning the third dimension.
Four rats of the six were able to adjust accurately and imme-
diately to any direction of Platform II, (p. 92). A fifth
was successful in five out of twelve trials including the first.
The sixth rat, (when she was not jumping through a slit in
the canvas before the cabinet was lined with other material)
made the adjustment correctly in five trials out of six.
'Wataon (^Animal EJucetioa, p. 85) remarks "other diings being equal,
rao ihow a decided preference for welt-li^ied rather than dark places."
Digilizcd by Google
101 FLORENCE RICHARDSON.
In the experiment in which both the distance and direction
were changed, the two rats tested made the successful coordi-
nation. In this test, it will be recalled, the rat was obliged to
jump downward and outward to reach Platform II, a hori-
zontal distance of i6 inches from, and a vertical distance of
lo inches below Platform I. The downward jump had not
hitherto been required in the experiment, and the animals
accommodated themselves to the change immediately. Pos-
sibly this immediate accommodation was due to the fact that
Platform II, being lO inches below the level of Platform I,
afforded a visual stimulus area about four times larger than
when in the horizontal plane of Platform I. The stimulus was
thereby much more effective. This fact of instant adjustment
to >a directional change, and a trial and error method of adjust-
ment to a merely distance change, is the basis for the assumption
that vision (or some other unknown distance receptor) affords
information as to the direction but notastothedistance, of the
stimulus. The observation that while the animals could jump
downward to Platform II at i6 inches distant horizontally
from the support of Platform I and lo inches below it, but
not at 8 inches horizontal distance [and lo inches below] con-
firms an earlier statement that vision is in many instances
overruled by the habitual innervation tendency.
The possibility of a directional factor seems to receive some
confirmation in the results of the test. Of the eight cases of
miscoordination (not due to jumping toward the canvas)
four were jumps toward the east, the direction in which the
jump was learned, and four were toward the south, the direction
of the first jump after the change. What the nature of such a
factor may be the present test made no attempt to investigate.
Whether it was this factor which led to the breakdown of the
coordination in the case of every rat but one is a question which
only further experimentation can solve.
Digilizcd by Google
PART SECOND
A. EFFECT OF TRAINING UPON THE RATS.
/. Experimental Results.
I. Comparison of Records of Trained and of Untrained Rats.
a. Normal White Rats on Problem I.
While training two female white rats upon Problem I for
a purpose other than that of these tests, it was found that their
time-records were lower than normal. They had previously
learned the Hampton Court maze. Thinking that this lower
time record might be the result of tuition, the records of these
rats were preserved in order that they might be compared with
those of normal untrained animals upon the same problem.
In Table XII is given the averages of the trained and of the
untrained groups; and on Plate V is shown the averages of
both groups.
Table XII.
Sbtwittg (l) ibe average time-recorJ of 8 untrained normal vibile rati, (l) ibe
aoerage time^ecori of tmo trained normal wbiu ratt, and (3) ibe time-recordt
„f„,r.i.,JUi
J anojmic rat upon
PniUml.
NO. OF TRIALS.
I.
2.
3-
J
7. 04
Ts?
■S5
Z
1.69
-23
.18
3
.*«
09
■30
4
.80
«
.12
5
■35
.10
.07
6
■30
■05
.11
7
■25
■09
8
'3
.06
9
-27
OS
30
10
.18
.12
It
.16
■"S
■05
12
■■3
-"4
.08
DiBiiizcdbjGoogle
FLORENCE KICHARDSON.
Table XII. — Continueci.
KO. or THIALS. I
2
3-
'3
'S
05
17
'4
09
OS
OS
15
II
OS
22
14
14
•7
■8
08
12
tS
'3
04
07
19
19
06
22
10
09
04
OS
21
17
06
22
u
06
05
■ 23
II
07
10
24
33
37
II
25
14
07
05
26
10
27
08
'5
04
28
11
06
OS
29
'5
10
04
30
07
09
08
31
07
06
06
32
06
05
OS
33
12
07
06
34
'7
05
07
35
09
IS
07
36
'9
05
12
37
'4
04
07
38
09
05
10
39
09
05
10
40
09
03
07
41
2+
0+
08
41
IS
06
09
43
OS
06
44
II
21
14
45
10
04
05
46
06
04
05
47
06
OS
07
48
06
06
49
06
OS
05
SO
23
04
07
The comparison shows that the averages of these trained
normal animals are far below those of the untrained normal
white rats. The average of their records is — in themain —
below the minimal time-records of the normal untrained group.
DigilizcdbyGOOgle
A STVDT OF SENSORT CONTKOL IN THE RAT.
Digilizcd by Google
■o6
FLORENCE RICHARDSON.
The average of the lowest two records of the normal group is
considerably above that of the average of these two experienced
rats. No conclusions are justifiable upon the results of this
comparison, since the two animals might have been extreme
variations. The records are, therefore, tentatively put forth
in connection with those of other trained and untrained groups.
The records of these two trained females averaged by tens
in a series are given below. They may be compared with other
records of the same kind on p. 2i.
Th Averagf Time-RecoTdi of tbtlwo Ftmaltt {or Enliri Serin.
19
Averagi Time-Rei
Female II
.,, ,j T„
l-IO. .
11-20 .
21-30..
■ /. Ftm<iii 11.
! .71
Female I made a total of five errors, and Female II a total
of six errors in the series.
b. Blind Anosmic Rat on Problem I.
The time-records of the blind anosmic rat upon this problem
are given in Table XII. He had been trained in the maze
during a long series of tests. This rat was undoubtedly a very
robust animal. His records on Problem I are much below
those of the untrained normal rats, the blind rats, or the anos-
mic rats with vision. He became very active when put into
the control cage and attacked the problem at once.
The Aviragi Timt-Record for Entire Series (50 Trials).
Blind Anosmic Rat 10 mm-
Average Timr-Rrcordi by Groups of Ten.
\l-ixt .
21-30. .
DigilizcdbyGOOgle
A STVDT OF SENSORr CONTROL IN THE RAT. 107
This record may be compared with those of the other rats
which are given in the section on Problem 1 (p. 21).
Each of the two curves, representing the averages of rats
which had had previous training, are lower than any one of
those representing the averages of untrained white rats.'
c. Normal White Rats on Problem III.
Four untrained normal white rats were set to work upon
the problem. Three of the animals were males about 150
days of age, and one female 128 days of age. The method of
conducting the experiment was the same as in the earlier test.
The rats were tame and in good physical condition.
Their method of solving the problem was the same as that
of the trained animals, except that the untrained rats con-
sumed much more time in achieving their hrst successes. The
minimal time record for the first trial was more than 29 min-
utes. The rats were energetic and industrious, but they
spent a great deal of time examining the control cage, though,
like the trained animals they had been fed for three days in
the cage to accustom them to the environment. Their average
was not reduced to one minute until the fifth trial. The
averages of the trained rats on the other hand did not go above
one minute after the first trial. The averages of the untrained
rats were reduced to. 10 min. at the twenty-first trial though they
were higher thereafter; while the averages of the trained animals
dropped below .10 min. on the seventh trial and were later
no higher.
Table XlII and Plate VI show the averages of these trained
and untrained animals.
The curves show very plainly the great difference in time-
records of the early successes and also show the fact that
even from the thirty-fifth to the fortieth trial the records of
the untrained rats were not so low nor so uniform as those of
the trained rats from the tenth to the fifteenth trial.
' In view of a possible difference in the function of vision between white rati
and those having pigmented eyes, it is no more than fair to limit the comparison
here to record) of albino rats.
Digilizcd by Google
I08 FLORENCE RICHARDSON.
Table XIII.
Showing the average lime-recordi of traituJ and of untrained normal whiu rati
onProbtemlll. The first column of averagei represenlstbt group of leven
trained rats; the lecond, the third, and the fourth columns, the average, the
m, and the maximum time-records of the untrained rats.
NO. OF T1UAL.
AVERAGE. AVEI
lAGE. MINI
-UM. «AX„
™.
-i.n. mi
». m«
I
5-72 40
14 29
IS 54
38
2
■32 5
97 2
76 13
'7
3
■33
80 1
28 II
17
4
■7 7
77
61 13
«7
5
.29
92
45 1
17
6
.22
91
SS '
'5
7
.09
99
IS 2
55
8
.09
37
07
98
9
.06
43
11
75
10
.06
28
20
43
II
.07
24
12
37
■2
-05
«3
08
=S
'3
.05
22
07
35
1+
.05
23
14
30
•5
■OS
23
'3
35
i6
'S
10
=5
17
10
45
18
19
12
27
'9
08
43
20
II
05
18
09
03
21
22
08
03
18
13
08
03
'7
2+
10
03
18
2S
17
58
26
08
03
27
07
04
10
28
06
03
10
29
06
03
■5
30
04
03
»5
</. Normal Black-and- White Rats on Problem III.
Table XIV and Plate VII show the averages of the trained
and untrained groups of black-and-white rats on this problem.
The difference in the two curves is rather startling and calls
for some descriptive comment.
Digilizcd by Google
A aruor of sensort control in the r4t.
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1
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if
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mJ-S -:i.|-i.S
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:::3:: :
ir^
' ' ' I'll 1 1 1 1 4-I4-L4- -4-
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DiBiiizcdb, Google
FLORENCE RICHARDSON.
Table XIV.
Showing the aueragt timfrecorJt of traineJ and of untraintd normal ifaci-anJ-
vAiU rail on Problem HI. The firit column gives the avtraget of the trained
amimaii; the second, tbetbird, and tbe fourtb, give respectively the averaget,
t, and the maximum time-rrcorJi of tbe untrained animals.
HO. or ^^g^
TMAl.
.c. .v..
CE. HIMU
*"**■ MAxr
«,«.
I
99 7
09 I
61' n
%
3
49 4
97 3
41 6
42
3
12 I
23
T >
70
4
29 2
76
32 4
2S
S
09 9
15
40 25
78
6
II
76
43 1
33
7
07 2
4+
63
8
04
67
4>
87
9
08 I
35 ■
00 t
95
lo
06
57
18 I
28
II
14
21
II
28
12
04
23
18
28
'3
OS
80
07 I
42
14
07
■5
07
27
"S
04
18
■3
22
i6
07
ZI
'3
32
'2
04
11
08
17
i8
04
10
03
17
'9
06
•4
09
22
20
08
>4
05
28
21
09
08
"7
08
22
OS
07
04
18
23
04
lo
05
10
M
04
08
°5
07
25
04
05
04
09
26
04
"7
OS
08
27
03
09
07
28
05
10
»5
■5
29
08
07.
10
30
06
"5
07
31
04
03
07
3*
06
04
08
33
05
04
d6
34
04
03
08
35
07
04
36
05
04
06
37
»5
07
06
38
i>7
06
06
39
05
04
05
40
06
OS
07
DiBiiizcdb, Google
A STUOr OF SBNSORT CONTROL IN THE KAT.
Digilizcd by Google
112 FLORENCE RICHARDSON.
T^e untrained animals were tame but naturally not so tame
as the trained rats when they began on this problem.' Two
of them were frightened by the opening of the door: one rat
was particularly careful not to approach the door from the
front, but came up to it cautiously from the left so as not to
be too near wiien the door should fly back. The rats did not
locate the position of the door at once as the trained animals
had done. This is doubtless one cause of the very high aver-
ages up to the tenth trial, the other apparent cause being the
avoidance of the door.
e. Blind Rats on Problem III.
The experimenter desired K) complete the comparisons with
a discussion of differences as shown in the records of the be-
havior of experienced and inexperienced blind rats on Problem
III. When the records were assembled it was found that the
individual and accidental variations were so high among the
defective animals that the averages of so smalt a group would
be valueless in a comparison. Table XV shows the time records
for each individual.
At the time of the experiment, but three inexperienced blind
rats were available. Of these one made exceedingly poor
time records for the first ten trials of the series, and his generally
poor records throughout were a marked variadon. Another
animal made uniformly poor records as compared with the
experienced blind rats, while the third rat was by far the most
active of the twelve bHnd rats that were experimented upon.
His records represent a marked variation in the other extreme.
Consequently, an average of the records of these three animals
would be valueless as a basis for comparison with any other
group.
'The untrained animals were all of one liner, were no days old, and were
of the same parentage as the litter of trained rats. The mother of the rats was
the most active and energetic animal that had been tested in any of the ctpcii-
Digilizcd by Google
A STUOr OF SBNSORr CONTROL IN TBE RJT.
Table XV.
Sbaun»g tbt iMJiviJmal litae-rtcordt of tbrte
•i blind Tall OB Probltm Hi.
NO. OP TRIAL.
HALBI.
FEMALE I.
I
. 1
77
6
32 6
47
2 1
45
■5
72 >
30
3
28
35
65
4
28
I
87
28
5
18
4
■7 3
50
6
30
s
'3 >
03
7
12
6
37
S3
8
■5
S
S3
97
9 10
15
73
80
lo
18
18
55
65
II
12
«5
98
90
12
'3
12
42
41
'3
12
I
08 1
45
•«
'3
45 I
33
■S
12
20 3
50
■6
08
to
98
10
■7
I
87 I
95
il
27 ■
'7
■9
I
"5 2
28
ao
I
57 ■
92
21
25 '
S8
22
28
88
»3
I
60
78
H
I
02
05
'S
27 '
32
26
I
56
95
«7
'7 '
87
2l
20 I
28
»9
37
75
3»
I
38
68
3'
57 ■
II
3»
»7
S3
33
93
43
34
32
60
35
'7
75
36
22
37
37
38
08
39
45
40
.1% 1
DiBiiizcdb, Google
114 FLORENCE RICHARDSON.
2. Summary of Facts Brought Out tn Foregoing Experiments.
The comparison of the time-records and of the learning
curves of each group of untrained rats with a group corre-
sponding in age, variety (albino, or black-and-white), and
condition (normal or defective) show that in every instance —
with the possible exception of the case of the blind rats which
cannot be cited as either confirmatory or contradictory — the
trained animals made uniformly better records than the corre-
sponding groups of untrained rats.*
II. CONCLUSIONS.
In view of the differences exhibited between the curves of
the several groups of trained and untrained animals, it seems
advisable to analyze the experience acquired in the solution of
the previous problems. The first consideration is the effort
to formulate a statement of: (i) What experience the animal
acquires in the previous series of tests, and (2) what effects
may be carried ever from one situation to another. Such a
carrying over might result either in a transfer or an interfer-
ence of training. The curves apparently justify the statement
that, within the limits of such problems as were here employed,
those rats which had had previous experimental experience
were more apt in learning a new problem. Trained animals
not only acquire the requisite association in a less number of
trials but the early time-records are shorter. Expressed in terms
of the neurological and physiological organism, die shorter dme-
record might be the result of a modification of either the motor
or sensory system, or both. If the modification were one
affecting the motor centers of the cortex and the efferent path-
ways, the stimulus might (l), release a greater amount of
innervation, resulting in greater general activity, or (2), release
movements which had become habitual in the earlier experience,
and which would be advantageous in the attempts to solve
the new problem, i. e., fewer random movements, and an
earlier accidental success would result. If the modification
'Yerkes (Th Dancing Mouie, p. 163) found that the acquisilionof one
labyrinth habit facilitated the acquisition of others.
Digilizcd by Google
A STVDT OF SENSORT CONTROL IN THE RAT. 115
were one affecting the sensory pathways and centers, the
general result would be (i) an increased susceptibility to the
stimulus — rendering the stimulus more intense — ^and (2) a
decreased resistance in the connections between thesensory and
motor centers, so that the indirect effect of the stimulus upon
the musculature would be more immediate.
Observations of the behavior of the two groups of animals
lead the writer to accept both of these possibilities as facts;
that the stimulus is more intense and the activity more imme-
diate and better coordinated in the case of the trained as against
the untrained animal.
Previous to the work on Problem III,- each rat had each
day for thirty-four days been lifted from the door of its living
cage, put through the door of the control cage upon the table
and allowed to satisfy its hunger from food which had to be
reached by its own exertions. It is reasonable to suppose that
after such a long process of habituation to such experimental
situations, the experience of being Hfted from the living cage,
carried to a distance and placed into another cage, might
become for the rat a stimulus to activity when placed in the
control cage.
In Problem II, given just previous to III, the entrance of
the problem box occupied the same relative position, i. e.,
on the lower left-hand corner of the south side of the food box.
When the trained rats were put into the cage containing Box
III, they went to this position and began to 'nose' about.
The contact sensations apparently released motor impulses
which resulted in the scratching, biting, pulling and clawing
at the spring, the latch, or the edge of the door. The first
success soon followed. When the untrained rats were put into
the cage, the environment was a stimulus to only the most
general and uncontrolled activity. The rats examined the con-
trol cage as well as the box. They sniffed at the food and the
latch, and then went on to examine other parts of the box and
the cage. They often sat down to wash their faces and scratch
themselves spending far more time at this procedure than did
the trained animals. Motor energy in these animals, in the
absence of any more specific stimulus, seemed to drainoff into
Digilizcd by Google
Il6 FLORENCE KICBJRDSON.
these reflex channels. On the other hand all problem boxes
(on account of past experience) served as potent stimuli to
the trained rats; the animals had satisfied their curiosityas to
the surroundings during previous tests and did not lack an
incentive to effort in the present environment. Therefore in
the case of the trained animals the stimulus released movements
which were more advantageous in the solution of the problem
than it did with the untrained animals.
The effect of the emotional attitude of the rat has been
disregarded up to this point. The emotional element is a most
important and ever present factor in the reaction of the
animals. The rats, as stated before, were tame at the begin-
ning of the experiments. They were accustomed to being
handled and when the door of the cage was being opened, they
came eagerly. At the end of the series this lack of timidity
had advanced to a point that might be called familiarity.
Instances of this were noted on a number of occasions when
rats became ill or aged and refused food in their cages, they
ate quite freely from food in the hands of the experimenter.
Accompanying the change in the emotional attitude of the
rats toward the experimenter is the change in the emotional
attitude toward the control cage and to problem boxes in
general.* When this part of the environment which is com-
mon to all the tests has lost much of its novelty, there is nothing
to interfere with the normal discharge of the impulses which
will speedily result in adaptive movements. Because the situa-
tion as a whole is novel to the inexperienced rat, there is a sute
of high emotional tension in which motor impulses, foreign
to the problem in hand, are set up by the strange sensory
' The same behavior as is here commented on as characteristic of trained
animals was observed in the case of two brood rats which were bought from a
$mall boy. Theae rats had absolutely no fear and exhibited no signs of distur-
bance when placed in strange experimental situations. Thereactionsof oneof
than which learned to jump a distance of 14 in. in thefirst day's test are detcHbed
on page 76, The other rat solved Problem III in much less time than any other
untrained rat. Her records are not included in the tables or curves as she was an
old rat and did not conform to the age requirement for these tests.
Theseinstancesarecited in support of the contention that the emotional tone
is a great (if not the greatest) faaor in the ease with which the rat adapts itsdf
to a new si
DigilizcdbyGOO^Ic
A STVDT OF SBNSORr CONTJtOL IN THE RAT. 1 1 7
impressions. In the case of experienced rats no such outburst
of motor energy is incident upon their introduction to a new
problem; consequently they are in a better position to begin work
immediately upon the elements in the situation which are novel.
B. INDIVIDUAL AND SEX DIFFERENCES AS SHOWN BY BEHAVIor.
/. Sfx Differences.
All of the tables giving the percentages of minimum and of
maximum time-records made by each animal (such as are
shown on p. 12) have been assembled and the following table
compiled from the total number. The animals are ranked
I, 2, 3, etc., according to the percentage of maximum and of
minimum time-records. For instance, the rat which made the
greatest number of minimal trials is ranked i ; the rat with the
next greatest number is ranked a. The rat ranked as 1 in
the portion of the table showing the rank in maximum time
records, is consequently the animal making the greatest num-
ber of maximum, or poor time-records. The table is shown
on next page.
The tabulation is of interest, showing as it does the compara*
dve ranks of the animal in the different problems. It is
rather striking that the greatest number of minimal records
made in mixed groups are, with one exception, to the credit
of the males, while in such groups the greatest number ofmaxi-
mal records are made by the females.' The least number of
minimal records, with one exception, were made by females
and the least number of maximal records were made by males.
The records are not a sufficient basis for any general statement
as to sex differences.
It is often, but not always true, that an animal which makes
a good record on one problem makes good records on the
other two. The ranking of the group of black-and-white rats
on Problem I and II are striking.
' This is noi true in Watson's work on the maze, in which the shonest recocdi
were made by the females. Yerl[es(Z)Dnfin^AfoN/f, p. 276)alEO Tound that the
females were superior to the males in the labyrinth test, although the males were
superior in discrimination tests.
Digilizcd by Google
FLORENCE RICBJRDSON.
Table ibouiing ttx and eomforative Tank of each animal m number of minima/
anj of maximal lime-recorJt on PrcAItms I, II. and II.
MINIMUM. MAXIMUM.
PROBLEMS. I. II.
III. PROBLEMS. 1. II.
III.
Normd While Rats.
Normal White Rait.
Malel
,
,
3'
o
Malell
3*
3*
4
o
Malelll....
3*
5*
4
3
Male IV....
3*
1
2
Female I...
7
of
I
ot
of
Female II..
4
o
6
S
I
Female III.
6
0
5'
3
Female IV..
5
o1!
4
^
on
Normot Black-and-Wbile Rat,.
Normal Blatk-and- White
Ra,.
Female],..,
1
t
o1
4
J
on
Female II...
3
3
01
3
4
oil
Female III..
1
3
3
Female IV..
+
4
'
'
'
Blind Rat,.
Blind Rati.
Malel
ot
ot
el-
ot
ot
Malell
ot
s'
ot
of
Male III.,.,
3
oil
4
oil
01
Male IV,..,
6
6
3
Female I,..
7
5
oil
I
o1
Female II...
4
oil
3
oil
Female III,
2*
3
oil
5*
oil
Female IV..
6
2
3
Female v.. .
5
^
3
5'
■
* Two or more animals attained the same rank in thete cases.
f Records noij included in averages but given under individual variations.
X Would not leam problems.
i Died before completing tests.
DigilizcdbyGOO^Ic
A STUOr OF SENSORY CONTROL IN THE RAT. 1 19
2. Individual Differences.
The following records of individuals are those which, for
the reasons given, were not included in the averages of the
groups, but are appended here for the purpose of comparison
with the average records of the group,'
PROBLEM I.
Blind Male I made 72 per cent of the total number of maxi-
mal records, although he made 10 per cent of the minimal
records. After the twenty-ninth trial, this rat made every
maximal record. From the twelfth to the twenty-fourth trial,
his records were unusually long, but after the twenty-fourth
his behavior was such as to render his records incomparable
with those of the other blind rats. He was slow and made
errors repeatedly. The animal seemed timid in getting down
from the top of the box. He was generally disturbed by die
experimentation, and would crouch and quiver when the
experimenter handled him. He became more nervous and
irritable as the tests proceeded.
PROBLEM II.
Normal White Female I was the slowest of the group of
eight normal white rats which were tested upon Problem I.
She was also the slowest of the group on Problem II, and
here her time-records represented a much wider variation than
in Problem I. In the second problem she was slow in her
movements and did not associate the act of stepping out on
the plane with the falling of the door of the food box. Between
the twentieth and thirtieth trials she established the habit of
biting at the string which connected the plane with the latch
of the door. She did not always go at once to the string and
often she made several efforts, — at one time six — before she
exerted sufficient force to throw it. These two causes of her
long records, as may be seen, made the results too variable to
he included in the average. In Problem III. her records were
even more irregular.
Yerkes (iHJ., p. 164 ff.) found wide and important individual 11
among his mice.
Digilizcd by Google
120 FLORENCE RICBJRDSON.
Blind Male I, the records of which on Problem I have already
been shown separately and commented upon, would make
no effort to solve Problem II, and as he seemed to suffer
from great timidity, the test was abandoned after five days.
Blind Male II was an active, healthy animal, and solved the
problem well in his first efforts and seemed to have established
the association by the twentieth trial, when he became dis-
turbed by the falling plane, — evidently its noise — and there-
after he avoided it. When he stepped upon it at all, he did
not step heavily enough to open the door. He made many
trips to the plane, then to the door; then u> the plane again, and
finally, when his efforts were entirely too erratic to be useful,
the test was discontinued.
PROBLEM III.
Normal White Female II made the maximum time-record
for the group at every trial. She was slow in her movements
and in addition often opened the latch while leaning downward
over the door from the top of the box. She sometimes opened
the door from the floor of the cage, but never until after she
had spent some time on the box. Consequently, her records
are given separately. In this problem as in the one previous,
she did not learn to solve the problem in the manner which
was customary for the other animals.
Blind Male II, which was not entirely successful in Problem
II did not in this problem reduce his records to an approximate
constancy even after fifty trials. His early time-records were
both exceedingly long and variable. The cause of the poor
records, as before, was slowness of movement, probably the
effect of his timidity. The sudden opening of the door fright-
ened him at the first trial, and he crouched motionless for half
a minute before he seemed to regain courage to move about
the cage. He avoided the locality of the door quite consist-
ently for many trials, and when he finally went to the door,
his movements were so slow and cautious the dme-records
were incomparable with those of the other blind rats. At the
end of a series of 78 trials, his time-records were still long
and variable.
A STVor OP SENSORr CONTROL IN THE RAT.
Showing Individual Diffnenc
et on Ibe Va
iou! ProbUmi.
PROBLEM I.
PROBLEM II.
PROBLEM III.
no. OP TXIAL.
Noimal
Normal
Blind
Male 1.
Whitt
Ftmale I.
Blind
Male 1.
White
Female 1.
Blind
Male I.
. 6.M
•55
■45
16.05
5 33
63
73
'9
74
25
5
.37
1 ' I
57
63
I
58
45
16
82
*
11
'5
'3
35
,
92
^
%
6
I
17
3
52
58
I
45
«3
42
7
37
75
43
1
41
11
9a
8
o8
73
60
36
10
5"
9
98
9
08
70
25
5
'>3
lO
27
55
83
22
6S
II
I
I
53
48
30
7
28
la
78
I
77
12
I
73
4
88
'3
II 1 [0
62
30
29
6
S3
14
15
I
27
12
28
1
13
IS
17
88
62
33
4
32
i6
37
22
20
2
39
»7
12
45
2
"7
s
78
tS
10
33
IS
3
37
19
33
■7
03
I
47
20
■S
13
75
2
05
22
25
■5
50
17
'3
3
47
75
13
43
04
28
42
24
18
05
33
37
as
■S
97
10
1
95
z6
85
1
28
67
30
27
2
62
3'
55
53
28
1
♦5
67
87
87
29
'3
42
n
I
17
30
1
79
22
82
79
3»
58
I
S8
6
n
IS
32
50
3
75
71
«5
33
59
'5
3
08
34
1
90
1
28
79
ii
1
08
48
62
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FLORENCE RICHARDSON
Table XVI. — Continued.
PROBLBU I
PROBLEM [I
PROBLBU III
Blind
Normal
Blind
Noimal
Blind
Male I.
White
Male I.
White
Male I.
Female I.
Female I.
40
■ 47
1 05
■42
+1
68
'5
85
4»
74
9°
I
S"
*3
I
16
98
97
44
t
13
I
3S
71
4S
.1
fA
S'
7"
46
«5
38
I
38
47
67
'7
S8
48
61
73
I
85
49
78
1
3"
I
17
50
.37
1-73
85
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PART THIRD
GENERAL CONCLUSIONS.
The following paragraphs summarize briefly and schemat-
ically the different conclusions drawn from the results of the
experiments above described:
1. No positive evidence has been revealed as to the comp-
arative acuity of vision in animals with albino eyes and those
with pigmented eyes.
2. The tests with three problem-boxes requiring manipu-
lation for solution afforded no conclusive evidence of the func-
tion of the visual impulses in the successful acdvibes of the
rats. The lack of vision, however, was disadvantageous in
proportion as the problem demanded finely coordinated and
narrowly localized movements.
J. In the test which necessitated a jumping reaction on the
pan of the animal, the visual stimulus apparently afforded a
basis for the proper control as to the direction in which the
jump was to be taken, but failed signally to afford any adequate
basis for accommodating to changes in distance only. The
visual impressions were not a sufficient control when the length
of the jump was changed and after a seeming struggle between
visual and kinesthetic factors, the coordination broke down
completely. Blind animals learned to jump considerable dis-
tances, but they were first given their orientation.
4. Olfactory stimulations had evidently little importance
in the problems here utilized. Such impressions were quite
as likely to interfere with, as to guide the formation of, the
requisite habit.
5- Tactual impressions, noticeably from the vibrissae,
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11+ FLORENCE RICHARDSON
seemed in these instances, to furnish a sdmulus for many requi-
site movements, but evidently did not assist in the following
of a pathway. The impressions afforded by the vibrissa were
utilized in locating projecting surfaces mainly in the vertical
plane.
6. The kinxsthetic and tactual impulses have been shown
to be of value in the different problems here employed. These
impulses were involved as essential factors in control not only
in the learning processes, but also in the reactions after they
had become habitual. In the tests involving jumping, in which
the conditions were changed after the habit had become estab-
lished, the animals were unable su£Bciently n> modify the
amount of innervation required, and, as shown above, the reac-
tions were consequently unsuccessful.
7. There were noted wide variations in the capabilities of
the animals both as to amount of activity and the capacity of
forming definite associations. There were wider variations
among blind than among normal animals. Slight sex differ-
ences were remarked, though the range of sex variation is less
wide than that of individual variation.
8. The effect of tuition among the rats employed in the
series of problems is evident. The animals which had had
previous experience in experimental situations were more apt
in attacking and solving new problems. This was doubtless
due to two causes: (i) that the situations had much in common,
so that a transfer rather than an interference of training resulted
and (2) that the decrease in emotional tension due to the com-
parative lack of novelty in the experimental routine made the
problem sdmulus more intense, therefore more potent, and
the resulting activiiy less diffuse.
lyCc
Psychological Monographs
NoveHber, 1H9
Whole No. 49
Psychological Review
SDtTSD BY
J. MASK BALDWIN
HOWARD C. WARREN JOHN B. WATSON
PanrenoH Dnivui>tt Johhi HoTKiHt DNiVEiiirrT
JAMES R. ANGEIX, D>n*»»iT or Cbkaoo {Riim tf lit PijcMmptJ Ummtptfk,)
On the Influence of
Complexity and Dissimilarity
on Memory
Harvey Andrew Peterson
Illinois State Normal University, Normal, HI.
THE REVIEW PUBLISHING COMPANY
« NORTH QUEEN ST., LANCASTER, PA.
AND BALTIMORE, MD.
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PREFACE.
While the investigation contained in the following pages
belongs to the field of pure psychology, the motives which
prompted it were considerations rather of educational psychol-
<^, and it is believed that not the least of its significance will
be found in its bearing upon certain problems in this latter
field. The experiments were carried out at the University of
Chicago during the year 1908-9. The subjects were eleven
graduate students in the Department of Psychology, of whom
seven were men and four women. Messrs. E. B. McProud,
W. C. Vogt, H. Kimmel, F. A. C. Perrin, J. W. Hayes, E. H.
Sutherland, and J. W. Baumgardner, and Misses Emma
Felsenthal, Mary C. Mcintosh, Edith Turner, and Jeanette
Obenchain. Two of them, Mr. McProud and Miss Felsenthal,
were obliged by pressure of other work to withdraw after the
Gray and the Violet Sets and the Renaissance Set had been
completed. Their places were taken by Mr. Baumgardner
and Miss Obenchain. In the latter part of the year supple-
mental experiments, described in V-3, were carried out with
Messrs. Sutherland and Hayes and Miss Turner. They did
not participate in the earlier experiments.
For the splendid spirit in which all eleven carried out their
part of the investigation I wish «> express to them my deep
appreciation and heartfelt thanks. To Professor James R.
Angell, Director of the Laboratory, and to Professor Harvey
Carr and Dr. Karl T. Waugh 1 am glad of this opportunity ro
express my sincere thanks for assistance in the formulation
and execution of the work.
Harvey Andrew Peterson.
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CONTENTS
I. Hictorical Introduction and Pioblem
III. Experiments with Language Materials
rV. On Methods of Learning and Testing Nonsense Syllables
V. Experiments with Kane Areas
1. Adding Variations to a Material Containing in Itself L
Variation
2. Adding Variations to More Varied Materials
3. Methods Employed bythe Subjects in Learning the Series.
4. Analysis of Errors
5. Other Experiments with the Same Bases
6. Analysis of Errors
VI. Individual Differences in Speed of Memorizing and in Retentive
VII. Experiments to Determine the Value of Arranging
VIII. Conclusion
IX. Appendix
I. Plates
I. Description of Series
3. Analysis of Errors in V a
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ON THE INFLUENCE OF COMPLEXITY AND DIS-
SIMILARITY ON MEMORY
Harvey Andrew Peterson
i. historical introduction and problem
The question of the relative persistence in memory of differ-
ent kinds of materials has been worked out to a considerable
extent. It is known that words in the form of connected pas-
sages are vasdy better retained than an equal number of dis-
connected words or phrases; and that objects, actions and
pictures are better retained than their verbal equivalents. Num-
bers and abstract words belong to the third stage of difficulty,
while nonsense syllables are the most elusive and most quickly
forgotKn of all materials commonly used for experimentation.
Presentation of the materials to several senses is more effective
than presentation to one only. Up to a certain stage — ^where
die limit is we do not know — complex material is retained better
than that which is simpler; and recurrent similarity in the
presentadons of series odierwise different is disastrous. Why
all this should be true is not so easy to find out. There has
been little attempt to seek explanatory principles which would
unify these diverse facts. The relations of complexity and
simibrity are both intricate and close. It is believed that a
comprehension of their relations will afford a unifying principle
for some of the other facts we have enumerated. These rela-
tions are apparendy somewhat as follows, so far as they have
been worked out. We may first take complexity.
A thing is complex when it has many parts and the parts
have many interrelauons, that is, the whole has a high degree
of organization. A telephone exchange is complex when in
operation, while a corresponding quantity of wire, colored
glass and electricity is simple because unorganized. But the
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2 HAtLVEr ANDRfW PETERSON.
fewer the parts the simpler the whole because the possibilities
of interrelation are less.
Complexity affects the memory through interest and atten-
tion- The simple is easily mastered. The parts and their
relations are few and the content is soon exhausted. The
complex, provided it is not too far beyond us, whets our curios-
ity. It gets the attention and the thing is in so far better
remembered, because it stays in consciousness long enough to
make a deep impression. But the complex has a superiority
in recall as well as in presentation, because of the high degree
of organization. This makes it a unity. One part brings
others. A general idea of the whole is also a very effective
starting point for recall. We pass to the experimental litera-
ture.
Meakin demonstrated the superior persistence of the com-
plex over the simple in passive attendon.' He exposed a line
and an angle together for five seconds directing the subject
looking at them to divide the time equally between them. As
soon as the exposure was over the subject closed his eyes and
remained passive for sixty seconds reporting the entrance and
exit of the two images. The angles were in consciousness an
average of 38 seconds; the lines, 32 seconds. In the same way
he compared plain figures and identical figures with concentric
lines just inside the periphery, plain and identical colored
figures, and figures of less and of more complex outlines. His
resultswere, for the plain and the marked, 24 and 37 seconds;
for the plain and the colored, 31 and 38 seconds; for the simple
and the complex outlines, 27 and 35 seconds.
Binet and Henri compared the memory of school children
for disconnected words and for sentences, the material being
read to the children.* Although the comparison was not car-
ried further than lists of seven or eight words, it was found
that about twenty-five dmes as many words were recalled from
the sentences as from the fists containing equal numbers of
words. The reproducdon was immediate. Mere connecting
words in the sentences were disregarded.
' Ptycb. Rtv., 1903, Mon. Sup., no. 4, p. 135.
* Binet and Henri: U Annie Ptycb., 1894, I, 1-59.
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4 HJRFET JNDREfF PETERSON.
ures give the average number of repetitions required for learn-
ing and releaming.
Firii Stttad
¥\un ayllables shown in one place 7.05 4.06
Hain syllables shown in nine places 6.60 5.63
Plain syllables shown in one place 6.04 5.40
Colored syllables shown in one place 5.61 2.79
Colored syllables shown in nine places 5.27 5.36
Dr. Gordon su^ested that the advantage of increasing the
complexity in this way would soon reach a limit, where more
potential clues would be offered than the learner could use in
so short a dme of learning, and where distraction would begin
to operate. It is the main problem of the present investigation
to find these Hmits in a few typical cases.
If the mind loves complexity somewhat, it loves variety and
change at least as much, — common sense would unhesitatingly
say, more, — and here again it is through the superior hold
which variety has on our attention and interest that the memory
IS improved. Let us first distinguish the pair, variety and
sameness (or similarity), from complexity and simplicity; for
though they have much in common they are not identical. Two
things are varied when one is more or less di'fFerent from the other,
has something not contained in the other. It is true that variety
presupposes complexity, for without a plurality of parts and
relations some of which are now included and now left out,
variety is impossible. But the converse is not true, for the
same complex may recur without affording much variety. The
simple usually has sameness about it, though it may have that
low order of variety which comes from a mere change of parts,
as when one changes from a collection of colors to one of letters.
There is little complexity in either because of the relative
absence of organization. The distinction which will be signifi-
cant for the present investigation is the fact that one might in-
crease the complexity without necessarily increasing the variety.
It is the varied complexity which in our opinion seems fruitful
for memory and which the present investigation is concerned
with.
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INFLUENCE OF COMPLEXITT AND DISSIUILARITT ON MEMOSr. 5
The beneficial effect of considerable variety upon memory is
a commonplace. A speaker who uses only a few tones is at a
disadvantage compared with one who uses intonation properly.
School programs rotate their studies with an eye to variety, and
not only interest but memory directly profits by the change.
Much of the bad effect of prolonged sameness in work is trace-
able to fatigue, but not all, as we shall see. All memoiy is
associative. There is no such thing as memorizing things
without relating them. With prolonged sameness or similarity
the associations derived from a presented material, quite apart
from fatigue, become confused with one another, jumbling
begins, and the memory weakens, unable to straighten out the
tangle of similarities. On the contrary the dissimilar are much
more easily kept apart, and fatigue is less.
In the experimental investigations variety is quite commonly
spoken of as vividness. Miss Calkins' investigation is well
known.' Numbers were associated with colors in couplets,
twelve couplets constituting a series. To speak first only of
the vividness experiments proper, all the numbers in a series
except one were black two-place numbers, the one remaining
was a three-place number or had red figures, or was differen-
tiated qualitatively from the others by some other similar means.
One of the ordinary numbers was associated with the same
color as the vivid' number. Thus the series of twelve couplets
consisted often ordinary couplets, one critical couplet, and one
so-called normal couplet which competed with the critical in
recall. The ordinary and normal couplets were two different
standards of comparison for the critical pairs. Tn the test for
immediate recall the subject was shown the colors in altered
order and was asked to give the numbers which had been
shown with each. The repeated color was shown only once.
It might recall the vivid number alone, or both the vivid and
the normal number, or the normal alone. The vivid number
was recalled 52 per cent of the possible number of cases, the
normal 21 per cent, while the general average of recall for the
ordinary combinations of all the series was 26 per cent. Thus
■ Calkiiu. M. W.: Association, Piycb. Rev., 1896, Man. Sup., no. i.
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6 HASVET ANDSIW PETERSON.
we have a measure of the effectiveness ofthis kind of vividness.*
In other experiments the critical number was the same as the
rest of the series in all respects save that it was repeated three
times. This measured the effectiveness of repetition. In a
similar way other experiments tested the worth of the first and
last positions in the series (primacy and recency). All four
kinds of critical couplets were superior in recall to the ordinary
and the normal combinations by varying amounts.
The analysis of the relations of sameness and variety made
in the preceding pages leads us to an interpretation of this
experiment which is quite different from that of Miss Calkins.
Just because there was only one of the critical pairs while there
were eight or ten of the ordinary pairs in a series, all four ^pes
of experiments (vividness, frequency, recency and primacy) are
studies in the effect of variety. All four of the critical couplets
are a change from the sameness of the other couplets of the
series. The superiority of the frequent couplet for example
is due in some measure to the fact of its repetition. But its
superiority is due quite as much and perhaps more to the fact,
already mentioned, that the other couplets of the series are all
pretty much alike, while the frequent couplet affords a change,
amid sameness. It is extremely probable that if the relations
were reversed, the mass of the series being given the threefold
repetition and the critical couplet being given only once,
the critical couplet would still be better remembered, providing
that the subject knew which was the critical couplet when he
saw it.' In the experiments of Miss Calkins on frequency the
second repetition of the critical couplet furnished this clue.
The isolation of the frequency factor from the sameness-variety
factor could be secured only by repeating one-half of the series
a larger number of times Jian the other half.*
' The italics are ours.
' "It ji not the mere intensity of the stimulus which is effective in attracting
the attention so much as it is the change in intensity. ... A negative
change will have the same general effect." Pillsbury: Attention, pp. 18-19,
The same is true of memory to a less extent.
* The question has been worked out with nonsense syllables in the fonn of
che worth of the individual repetitions. Cf. Ebbinghaus: Cruni/>u;r.tf.i*i7rW..
I, p. 652. Zweite Auflage.
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INFLUENCE OF COMFLEXITT AND DISSIMILARITT ON MEMORT. J
Take next the results on primacy. Suppose that the length
of the series had been three couplets instead of twelve, and that
the color which had stood in the first place had been repeated
in the middle place with a different number: Would primacy
have been worth any more than normal (here the middle) ?
Probably not. Then primacy is purely another form of vivid-
ness. There is no other factor involved, as there was in the
frequency case. The experiments on recency involve two fac-
tors, recency and sameness-variety. The worth of the former
is attested by the fact that in memory work in general the
terms just preceding the last are better recalled than their im-
mediate predecessors. But the last term is so very much better
recalled than the term just preceding it (which is almost as
recent), that the sameness-variety factor is much the larger one.'
To summarize the foregoing criticism, frequency and recency
improve the memory apart from the question of sameness and
varie^. Vividness and primacy are simply species of variety.
But the fewness of all the critical combinations compared with
the large number of ordinary combinations gives the critical
ones the advantage which comes from a change from the rou-
tine, and in view of the greatness of the numerical dispari^,
the whole investigation is a study mainly of different forms of
vividness or, in our own terms, of variety.'
Aside from Miss Calkins' investigation, and the one by Dr.
Gordon already described (which may be viewed as an experi-
'Cf. Ebbinghaus: Op. cit., p. 653. Miiller and Pilzecker: Zlub. f. Piyeb.,
1900, ErgSntangstJ. 1, p. 264.
' It is significant that the percentages of recall for the nonnal numbers were
usually less than that of the ordinary combinations. The fact is another illus-
tration of the disastrous effects of similarity. The critical color and the normal
number together are similar to the same color and the unusual number taken
together. If ab be stands for these two couplets respectively, given b (the
common color), a has by no means as Titchener says {Expertrntalal Psychology,
vol. I, pt. II, p. 407) "a chance equal to that of the other terms of the series,"
for it is interfered nith by a competing association, be. For the same reason
the figures ^ven for vividness, frequency, etc., in to far underestimate the value
of the factors since interference is always mutual. Of course the factor of
dissimilatity contained in them much overbalances the interference.
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8 HARVET ANDSIW PBTEMSON.
mem either in variety or in complexity') the writer is not
aware of other experiments on the positive effects of variety.
There are however a number of important and extended
researches on the negative side, namely, the injurious effects of
increasing similarity of associations, in comparison with which
the material free from the similari^ is relatively varied.
Miiller and Schumann found that syllables which had been
used once in old series were more difficult to learn in new series
than syllables which had not been used before.' The old asso-
ciates either appeared in consciousness and hindered the forma-
tion of the new connections, or there was a purely physiological
interference manifested by the poorer recall. Here the old
series and the series in which they were used again constitute
together the less varied material, while the series not re-used
are the more varied material.
Miiller and Pilzecker made an exhaustive study of interfer-
enct using nonsense syllables.' These experimenters demon-
strated that in the case of two associations of the type ab be
the interference is mutual. Their method was in principle the
same as that of Miiller and Schumann, except that they em-
ployed the method of successes. Each day the subject learned
four antecedent series and an equal number of sequent series.
The antecedent series were normally constructed eight-syl-
lable series. They were read in trochaic rhythm, hence each
series fell into four feet, a foot containing an accented and an
unaccented syllable. The series were given a fixed number of
repetitions and in the recall (to come later) the subject was
given the accented syllables in altered order and asked to give
the unaccented ones which had accompanied each. After
' Becauce the increase was in the direction of diiiimilar cotnplenity. The
■patial positions and the colon which were added to the syllables were them-
selves varied.
' Miiller and Schumann : Exp. Beitnige zur Untersuchung des Gedachtnisses.
ZUch. f. Ptyib., 1894, 6:177 and 318. Also Miiller and Pilzecker, who on
p. 83 in the work referred to in the following note summarize Mullet and Schu-
mann's results.
* Miiller and Pilzecker: Exp. Beitrage zur Lehre vom Gedachtnisi. Zutb,
f. Ptyeb., 1900, Ergiinzung^bd. I.
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INFLUENCE OF COUPLEXITT AND DISSIUILABUTT ON UEUORT. 9
learning the four antecedent series the subject was given the
four sequent series. These were formed by combining two of
the accented syllables of the antecedent series with new unac-
cented syllables. This furnished two of the four feet, and the
other two were made of new syllables. The series may be
symbolized thus:
Antecedent series: nb cd ti g^.
Sequent teriea: ij ak Im m.
After learning the four antecedent and first sequent series the
subject was tested on the first antecedent and the first sequent
series. Then followed the learning of the second sequent series
and the second pair of tests, and so on till all eight series had
been learned and tested. The half of the couplets represented
by the letters cd, gh, ij, and Im may be called die normal coup-
lets; the other half, ab, ef, ak, and en, the interference couplets.
The former were simply a standard with which the interference
in the latter might be compared. When the antecedent series
was tested (by giving a, c, e, and g), k and n interfered with
the recall of b and f. When the sequent series was tested (by
giving i, a, 1 and e), b and f interfered with the recall of k and
n. The following are Epical results.
Perctntage of Comet Rtealls.
(Number of couplets 168)
Per cent
Normal Couplets, Antecedent Series 66
Interfetence Couplets of same 36.5
Normal Couplets, Sequent Series 63.5
Interference Couplets of same $t.$
The next day the tests were repeated and the relations of
the two interference groups to their respective standards were
found to be reversed. It was now the sequent series which
showed by far the greater loss. This reversal is a study in the
effects of recency, into which it is beside our purpose to go.^
' While the second learnings were still fresh in mind a and e suggested their
second associates without mach difficulty. But when the tests were put off or
repeated later, the first associates became the stronger.
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10 HARFEr ANDREW PETERSON.
The extent to which the interference might go may be seen in
the fact that in some cases the interference recall in both ante-
cedent and sequent series together was less than the normal
recall of the antecedent series.
It is probably unnecessary to point out the relevancy of these
experiments to the question of the effects of similarity and
variety upon memory. The normal couplets are relatively a
more varied material than the interference couplets. While
the sameness in the latter is planned with malice aforethought,
so to spealc, the same thing happens in daily experience where
the sameness is unintentional and not so exactly measured.
The experiments of Ranschburg with numbers, described below,
illustrate how daily experience is full of the ab be type of
similarity.
Ranschburg has confirmed the results of MuUer and Pil-
zecker and Miiller and Schumann.' Most of the details are
omitted here because of their similarity to the two works last
described. Using the method of successes this author arranged
what he calls heterogeneous and homogeneous series. The
heterogeneous were simply normal eight-syllable series. Of
the homogeneous the frst series was also normal, but the rest
were not, for they were all identical with the first in respect to
their consonants. Only the vowels were changed in each suc-
ceeding series. These two kinds of series were learned in
parallel fashion. The confusing result may be imagined,
especially when an accumulation of eight series of each kind,
the learning of which had extended over a number of days,
was given a few renewing repeduons and then tested "run
together." His experiments with words are somewhat newer.
In these latter various series of word-couplets were devised in
which the words in a couplet were closely germane in thought,
but the couplets were drawn from quite disparate thought uni-
verses. In other series the couplets were internally as before,
but several couplets were drawn from similar and in some
cases practically the same thought universes. The similarity
' RanKhburg. P.; Ueber die Bedeutung der Aehnlichkeit beim Erietnco,
Behalten, und bei der Reproduction. J. f. Ptycb. u. Ntur., 1905, 5»)3.
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INFLUENCE OF COIUPLBXITT AND DJSSIMILARITr ON UEUORr. It
was entirely on the side of thought. In recall the subject was
very much more certain of the dissimilar series, and the per-
centages of recall were much higher than in the similar series.
In the latter the subject was quite apt to hesitate between the
correct response and a word in another couplet which was
similar in meaning, but might be quite removed in the time of
learning.
In another investigation on the conditions of perception of
similar and dissimilar numbers Ranschburg showed that the
fusion of similar things which we have seen talcing place in
memory exists even in the perception, when the time of expo-
sure is short.? Indeed he traces the memory confusion back
«> perceptual confusion, in cases where the successive presen-
tations possess considerable similarity. The experiment is for
this reason relevant to our problem: it offers an explanation for
a considerable part of the interference in similar memory
material. It is also important for our problem because it
endeavors to measure the degree of interference due to inherent
similarity, and not to the fact that the associations were made
to interfere. In experimenting upon the span and accuracy of
visual perception, using six-place numbers exposed one-third
of a second, Ranschburg observed that a large proportion of
the errors were traceable to the inherent similarly of certain
figures, for example 6, 9, and o, 3 and 8, 9 and %, i, 4, and 7.
He was able to determine the nature of the errors with con-
siderable certainty because in nearly all cases they involved
only one or two figures, and the figures were nearly always in
the fourth or fifth positions, less often in the third, from the
left. Where only one figure was wrong, it belonged in nearly
every case to one of the five following types; (i) Substitution of
a similar reproduced number, e. g., an 8 for a 3; (2) assimila-
tion to a similar nearby figure, e. g., 6842^3 instead of 6842^3;
(3) assimilation to a dissimilar nearby figure, e. g., 162^5
instead of 162^^5; (4) change of one of two identical figures to
any other figure; (5) substitution of a figure either preferred for
* Ranschburg: Ueber Hemmung Gleichzeitiger Reizwirkungen. Zttrb. f.
Pijth., 1902, 30:39.
Digilizcd by Google
II HARVET ANDREW PETERSON.
some temperamental reason or connected closely inexperience
with the given figure. The fifth seldom occurred. Where two
figures were wrong nearly all the cases were either simple inver-
sion (78 instead of 87) or a combination of inversion with one
of the types enumerated above. The first four classes of errors
are types of similarity. The fifth and inversion are not. The
large propwrdon of similarity Wrors makes it highly improbable
that they are due to chance.
In the light of this statistical analysis of the errors in num-
bers not devised to test similarity, but cut from a statistical
handbook, he constructed numbers of several different kinds
of similarity for the purpose of finding out whether "the
threshhold of perception is higher for homogeneous than for
heterogeneous material." In the first experiment he gave in
the same way as before 20 six-place numbers lacking similarity
internally, and 20 six-place numbers two figures of which,
usually in the right part of the series, were identical, e. g.,
1 1{74{75, or 14IPP3. In a second experiment the critical figures
were only similar. The results confirmed his hypothesis.
Where two of the figures were similar, the errors were about
three times as great as in the dissimilar numbers, but where
two figures were identical, the errors were four times as great
as in the dissimilar numbers. The threshold of perception is
therefore higher in proportion to the similarity. These figures
are valuable because they are among the few, to the writer's
knowledge, in which the amount of visual similarity is con-
trolled. Whether they bear upon the effects of similarity on
memory is another question. There is no objection to viewing
the responses of the subjects as immediate recall, providing the
conditions of exposure are comparable to the conditions of
exposure in memory work. It may be said that in memory
tests the subject is assured of a long enough interval to prop-
erly perceive the material. But it may be quite fairly said in
reply that while the absolute exposure is usually much longer
than was used here, the adequacy of it to distinguish the terms
from each other depends upon their similarity. I should say
that the conditions are comparable to those in memory in
many cases. On the other hand the confusion in such experi-
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INFLUENCE OF COiiPLEXlTT AND DISSIMILARITT ON MEUORT. 1 3
ments as those of Miiller and Pilzecker are not confusions in
perception but in memory.*
To summarize the various investigations of the influence of
relative sameness and variety on memory: anything which
serves to distinguish a thing from a group makes it better
remembered. A greater length) a different color, a more fre-
quent repetition, an unusual position spatially or temporally
are some of the variations which have been shown to be eff'ect-
ive. Where the similarity results from the triangular associa-
tion of two things with a third, if the recall proceeds from the
common element towards one of the extremes, the other extreme
interferes and diminishes the chances of recall. The result is
the same if the start be made toward the other extreme. The
conflictmay be purely physiological, and apparent in conscious-
ness only as a delayed recall. The injurious eff"ects of simi-
larity are however not confined to artificially constructed over-
lapping associations, but also occur where the similarly is
inherent in the nature of the material. In contrast with this,
wherever the diff^erent parts of the material learned are dis-
similar, the associations are more lasting and their recall pro-
ceeds more promptly, because they do not interfere with one
another. It has also been shown that the threshold of per-
ception is higher for similar material than for dissimilar. It
requires a longer time to get a clear perception of a material
the parts of which are similar than it does of one the parts of
which are not similar. The differentiation here referred to is
however purely involuntary and almost instantaneous. If the
perceiving process is cut off before clearness has been reached,
' Other experiments on ihe effects of simiUrity on memoiy are those of Berg-
•trom on the interference arising from sorting the same cards into different
arrangements of the same positions, in </in. your, of Psych., 1893, V, 356, and
1894, VI, 432. Also Miinsterberg, in Beitragt »ur Exp. Psych., Hejt 4, p.
69. Both of these deal with the interference of automatic habits of movement.
The latter shows how opposed habits, after being made automatic separately,
may be used for alternate periods of considerable length without interference,
e. g., keeping one's watch first in one pocket and then in another, the same arm
being used for both movements. It certainly offers something for reconcilia-
tion with the otherwise uniform outcome of the similarity lite
Digilizcd by Google
14 HARFET ANDRIW PETERSON.
the errors in recall are largely of the type of confusion of sim-
ilars.
Summarizing the inBuence of complexity on memory we
may say: the complexity afforded the mind by sentences or
connected passages is superior to the simplicity of disconnected
words because of the unity of the whole passage and the result-
ing greater dilFerentiation of the parts. In assimilating a
simple linguistic material such as nonsense syllables, letters or
even disconnected words, a person not only tries to give it a
unity by connecting it with his experience, but also seeks dif-
ferentials by which to distinguish the parts; and in theabsence
of preformed associations which may serve the purpose (for
example the English words suggested by nonsense syllables),
any peculiarity such as spatial location, background, etc., will
be utilized. But the peculiarities thus utilized are increases in
complexity. In these cases the secondary associations (loca-
tion, background, etc.) are formed during the memorizing of
the principal associations.
We are thus brought to the problem of the present investi-
gation. Two factors are involved which are inversely related
to each other. Increasing the complexity diminishes the simi-
larity, and this is favorable to memorizing. On the other
hand, // the materia! is not a unity in advance, complexity
increases the association processes, the mental effort presumably
required, and consequently the possibilities of distraction.
Under these conditions how much will variation added to a
material, highly similar in itself, shorten the learning time and
improve the retention ? Is there a resulting profit to the mem-
ory only when the original material is highly similar, or may
it possess considerable variety f When does distraction enter ?
Is there a relation between the amount of complexity which a
person will make use of and his retenriveness ?
II. APPARATUS
With slight changes the same apparatus was used throughout
the investigation. The essential part was an electro-magnetic
shutter which by its movements opened and closed a small
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INFLUENCE OF COMPLBXtTT AND DISSIMlLARITr ON MEUORV. 1$
aperture in a screen. The screen was 2 m. ir cm. long and
58 cm. high. Near the middle was an aperture 9.5 cm. wide
and 2 cm. high. The subject sat in front of the screen, and
when he looked at a series he brought his eyes within about
3 cm. of the aperture. Behind the screen, 74 cm. from it and
parallel w it, was a track somewhat longer than the screen,
supported by adjustable standards, and carrying a car i m.
long and 1 1 cm. wide. On the floor of the car and running
the length of it was a groove, into which any kind of series
EXPOSUKE APPAKATUa
The apparatus is described in the text. A ii apenurei E S, electro-mag-
nedc shutter; T, track; ^S, wide screeni C, car; A S, adjustable screent; L S,
lower screen; S, shunt; MB, metronome box; R B, rubber bands, upper and
lower, which limit the play of the shutter.
mounted on heavy cardboard could be slid preparatory to
exposing it. On the back of the car were four upright steel
rods 25 cm. high on the top of which were four spring clasps.
Small cardboard flaps on the back of the series when put into
the spring clasps held the series rigidly in place. Two black
screens 71 cm. high and 56 cm. wide, extending from the large
screen on the front of the tables to the track, could be so
adjusted by the operator as to confine the subject's gaze to as
Digilizcd by Google
1 6 BARVET ANDRilF PETERSON.
small a space as desired. They could be widened so as to
expose a whole series at once. The car would of course then
remain motionless during exposure. Or they could be narrowed
to the width of a single term of a series, 15 cm. for example.
For successive exposure the car would then be moved past
this space by the operator during the intervals while the aper-
ture was closed. The great advantage of the apparatus was
that whenever the subject was looking the series did not move.
A scale, 25 cm. in length on the front of the track, enabled the
screens to be quickly adjusted to any desirable width. The
operator was cut off from the subject by a strip of cardboard
extending across the upper part of the space between the con-
verging screens. The essential part of the apparatus, the shut-
ter, remains to be described. This consisted of an iron lever
55 cm. long carrying a movable counterpoise on the short
arm and the shutter on the end of the long arm. An electro-
magnet under the lever drew down the short arm when the
circuit was closed, at which the long arm carrying the shutter
moved up and closed the aperture. When the circuit was
broken a coiled spring connected with the wooden base drew
the arm down and thus opened the aperture. The current
was led first to the commutator, then through the electro-
magnet and a metronome. A small rheostat connected at the
commutator with the apparatus furnished a shunt to the current
at the moment when it was broken by the metronome. The
metronome, enclosed in a felt-ltned box, regulated the move-
ments of the shutter, while a small rod passing through the
wall of the box intercepted the pendulum or set it free when
desired. A j'ear's constant use of the apparatus has led to the
conclusion that it is a satisfactory exposure mechanism for
memory work of this kind.
III. EXPERIMENTS WITH LANGUAGE MATERIALS
The first effort was to extend the experiments of Dr. Gordon.
Series of nonsense syllables of the length used by her (nine
Syllables) were varied in size, color and style of type. The rules
of Miiller and Schumann were followed in constructing the
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INFLUENCE OF COUPLEXITr AND DISSlUIUtaTT ON MBMORr. 17
series. No syllable was used twice. The variations were first
tried out separately and later in combination. Variations in
size were secured by using Willson Gummed Letters numbers
I, 20, 21, 23 and 25. The largest letters were 38, the smallest
7 mm. high. The letters were all of heavy type, the lines of the
largest being 8 mm. thick. T^us a strong difference in sensation
was secured. A medium size, No. 21, was used for the standard
and colored series.' Colorvariationwasobtainedby painting white
letters red, orange, yellow, green, blue, brown, neutral gray, and
black. White furnished the ninth variation. In the series in
which the size varied there were two syllables in each of four
sizes and one in a fifth size, while in the color-varying series
each syllable was of a different color or brightness. Five dif-
ferent styles of lettering were used in the form-varying series,
all presenting, as nearly as could be, about the same area of
stimulating surface as the standard letters. The styles of
type used were the most varied that could be found and still
be legible. They were (i) a heavily shaded style of print,
{2) old English, (3) plain script, (4) an alphabet of closed letters
similar to the old English, but having more flourishes, and (5)
an alphabet of hollow letters. All of these were done in black
by hand. Four series of each kind of variation, size, color,
and style of type, were given to six subjects without varying the
spatial position of thesyllables.* Thusthevalueofeach variation
separately was obtained. Theeffectsof practice were distributed
by giving four series each week, one of each kind, and rotating
the time situation of each kind each week. A hard rubber
mouth piece held between the teeth was used to aid the subject
in eliminating enunciation. It was found as shown in the
table below that in immediate recall the series varying in size
gave slightly better results than the standard — a gain of 9 per
cent, but that color variation was of no aid, while variation in
the style of print was a detriment. In recall after 24 hours,
however, the result was quite different. Size was again the
'The standard series did not vary in siz«, color or style of type. They
were die itandard with which the others were compared.
' For further details, see p. 25.
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l8 HARFET ANDMW PETESSON.
best variation, showing a gain over standard of §8 per cent.
Co/or was next with 52 per cent gain, while even form variation
showed a gain of ig per cent.^
The next step was to increase the complexity by combining
the variations. In each syllable shown him the subject faced a
new combination. The most complex type were series which
varied in four ways: size, color, form or style of lettering and
spadal position. A second type varied in two ways only, the
two which in all probablii^ were the most effective singly,
namely, position and size. The third type was simply the
standard without variation in position. Four series of each
were given as before, and it was found that one had not far
to go to reach the limit of effectiveness in this direction. In
immediate recall the two variations showed a gain of 15 per
cent, while the series containing four was no better than stand-
ard, a gain of 3 per cent. In recall after 2^ hours the two varia-
tions showed a gain over standard of only ^ per cent, while the
four gave the same as standard again. The improvement shown
hy the subjects in the standard, jtS per cent gain over the show-
ing made in the first four weeks, is worth noting. It is due
to practice. The unexpected fact ts that the size variation with
the addition of position variation has not gained proportion-
ately. This is probably due to a concealed loss consequent
upon increasing the complexity. In any case taken with the
fact that four variations gave the same as none (5.21 and 5.21),
it shows that the limit has been reached vrith this material,
unless more effective variations can be found.
During the fifth and sixth of the eight weeks spent on syl-
lables, the combination of size and position, and the combina-
tion of four variations were tried with words. It was expected
that the variations would be of no positive value here because
words contain so much variation in themselves, especially in
meaning, as compared with syllables. The result as shown by
the table, based on two series of each kind, confirmed the
expectation. Interesting light is thrown by the introspections
of the subjects on the cause of the failure. They made mean-
'The tix horizontal rows of figures in the tables represent the six subject*,
and give the average number cl syllables or words out of nine correctly recalled.
dbyGoO^lc
INFLUENCE OF COMPLEXITr AND DISSIUILABITT ON MEMORr. 19
ing-cUssifications such as 'farm products' or 'machinery,'
which united not only two or more words in the same series,
but even words from different series. With rare exceptions,
position was the only 'mechanical aid, but even it was not
needed in view of the variety afforded by meaning. In sylla-
bles they found variety in ways not provided by the operator,
all of which is on the positive side of our thesis, but which
cannot be reduced to tables. At the outset of the experiment
the subjects were asked to lend their cooperation in shifting
the emphasis of the attention to the variations introduced by
the operator, and they did so. Nevertheless, resemblance to
words, despite their efforts to exclude it, was one of the two
main aids in recalling the syllables, the other being position.
The fact that an error had been made in the case of a certain
Table i. Sboiuiag mirragei and mean varialioni.
A. NONSENSE SYLLABLES.
ImmeJiatt Recall.
,rr^«
OMl tA
KtK IIMIHT.
StudlTd.
Caian.
Sim.
Fomu.
Sui]d.rd.
TwoVir.
FourVir.
Av.
M.V.
Av.
M.V.
Av.
.V.
Ai.
M.V.
Av.
M.V.
Av.
M.V
Av.
M.V.
6..J
LIS
6.8,
1. 01
7.92
..,
6.67
.SO
7-14
I.OO
8.4.
.39
7 00
-SO
6.6;
1. 17
'■7S
.4ft
7-41
1.04
tip
.79
6.SC
i.oa
I.OC
7-'i^
.80
TV
7-T
M
8.5c
.7S
6.0I
■ St
6. .7
b.f.
■ Qt
^V
«1
■i-JS
i-?":
4-Sc
6.0c
.8.
S 42
■qi
«.v
6.66
i.r
7.16
1.42
S-iS
.2(
!6J
■7;
b.i;
■ V
6.0(
.90
6., I
I.O&
!■';
1.0c
7-i;
[.17
7.o»
'■59
'.7S
M
5 33
SO
S 75
■ 75
5 33
i.oH
6.50
1.00
b.oo
I.OO
S3'
1.15
«.3S
■74
6.89
.68
s».
1.08
6,70
9'
7.68
1. 10
6.88
.96
Recall after Twenty-four Ht
.yGoogle
20 HARVEr ANDREW PETERSON.
B. WORDS.
Immtdiate Ricall Recall after Forlyeigbt Hoars.
Stind. Two V»r. Four V»r. S(ind. Two V»r. Four Vu.
7.2 7.00 6.1 1.94 3.40 1.69
syllable individualized the syllable and was likely to fix it.
Thus one subject said paradoxically that the syllables that he
didn't get in immediate recall were the ones he got in the test
for permanence.' For a while white type on white cardboard
individualized and fixated its syllables more than colors or
grays, simply because it was difficult to see. A doubt as to
the identity of a letter, after being settled, was certain to fixate
the syllable concerned.
If meaning is a kind of variety which persons naturally seek,
as the work with nonsense syllables and words indicated, it
should be susceptible to measurement. A series of twenty
adjectives, and another of twenty short sentences were given to
five subjects. The adjectives were :
Fat, humble, young, happy, broad, disiracted, violent, privileged, sleek,
Kversed, cautious, immediate, idea), polite, cold, gabled, serene, imaginative,
various, trifling.
The sentences were:
Mammoth Cave is a wonderful place. Cats are not very teachable. He
gave a prodigious snifF. The naval gunner is often a noble fellow. Chicago
is a windy city. Genteel is a word seldom used today. Damp weather is
bad for rheumatism. The need of protecting our industries is a worn argument.
The mistletoe is a parasitic plant. Dogs are sociable companions for men.
The theatre is potent for good as well as evil. Gambling is expensive. The
steamer hit the dock a hard bump. This thread is rotten. Parks at public
expense are easily justifiable. Granite is a handsome building stone. The
lake is rough. The Japanese are a small race. Is abusive language ever
justifiable ? The owner of the horse gave a sarcastic smile, and declined the
offer.
The subjects were allowed two minutes in which to study
each of the series, which were given them in typewritten form.
'The series were shown again between immediate recall and the test for
permanence See IV below.
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INFLUENCE OF COMFLEXITT AND DISSiMILARlTT ON MEMORr. 21
Following directions they did not run together successive terms
into larger units, and tried not to expand words into phrases
or sentences. They were required to read each list through at
least once. In the test for immediate recall and for retention
after twenty-four hours they were required to give only the
substance of the sentences, but the words verbatim. They
Tfcalled an average of 12.8 words and 11.6 sentences in imme-
diate recall, and y.6 words and 7 sentences after twenty-four
hours. One of the five did worse in the sentences than in the
words, the other four did as well in one as In the other. The
subjects said it was difficult to keep the words from arousing
mentally a thought-situation which expressed in language
would have been one or more sentences. Yet it is not to be
inferred that the two lists became equivalent. The tendency
existed in that direction, and the attempt to inhibit it was
partially a failure. The difficulty of controlling the material
led to its discontinuance. Perhaps the significant feature, aside
from the tendency toward expansion mentioned, is the fact
that the sentences are remembered as well as the words.
Numbers are a material apparently difficult to read connected
thought into, especially when given in extended series. They
seem at times not very far from a dead level of monotony. Yet
they may be vivified by associated material. Three series of
each of the following two kinds were given: on the one hand
series of two-place numbers, seven numbers in a series; on
the other hand three series of similar numbers and beside each
a biographical fact from the Renaissance period of It'ilian
history. The facts were varied and some were striking. One
of the series of numbers and facts was as follows:
Series III.
51 A sculptor.
95 Famous for an impromptu oration in Latin congratulating the Emperor
Frederick III on his coronation.
14 A merchant of Pisa. Introduced the Arabic aotation into European
commercial life.
47 A monk.
a6 Naples.
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22 HARVEr ANDHEfF PETERSON.
79 An instance of the revival of oraiory. Funerals, marriages and installa-
tions of bishops were among the occasions of his effoits.
85 A bishop.
It was expected that the numbers without facts would be
learned in less time than those accompanied by facts, but it
was thought that the latter might be retained better. Two
new series were given each week, one of each kind. Typewritten
cards each containing a series were given the subject, one
at a time. In the case of the numbers without the facts he
memorized the list as rapidly as possible, the time record being
kept by the operator with a stop watch. As soon as the subject
thought he could give the list correctly he tried. If he failed,
the learning process was resumed, and this continued until he
gave the list correctly. The next day the series learned on the
previous day was tested, and if an error was made, that series
was relearned, and so on until the subject held the series cor-
rectly for 24 hours. This was the standard of learning up to
which the series were brought before they were dropped. With
no subsequent renewings they were tested for permanence of
retention seven days and again thirteen days after the comple-
tion of learning. The series of numbers and facts were learned
in the same way, except that in the tests the subject was required
to give the substance of the facts with their appropriate num-
bers. We refer here to the learning process.
The results are given in Table 2. The first half gives the
total learning times in minutes and seconds. 3:31 means 3
mins. 31 sees. In the second half, in which the recall is given,
the figures indicate the number of numbers, or numbers and
facts which were correctly recalled. Seven would be a perfect
score for a series. No credit was allowed for partially correct
numbers, or for numbers or facts apart from their correct
coupling. Several cases where the recall could not be secured
are marked by dashes in the table.
The numbers alone are learned in less than one-half the time
taken by the numbers and facts, and are retained quite a little
better.
This ended our experiments with language materials. We
may summarize them as follows: Typographical variations
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INFLUENCE OF COUPLEXITT AND DISStMlLaHlTr ON MBMORr. 2$
Table 2. Rtnoiisance Stries.
LEARNING TIMES.
McP
G...
H...,
3:3
39 9
M
7
r. 10
"v
2t 7
V
4
49 10
2)
42 9
,6
6
23 8
6
9:37
5 :1S
:od 12
7
5:0s
4:07
3
9:21
5 S9
2 : S»^ 3 ■ H 9 ■ '4 7:15
7:4>
NUMBER OF TERMS RECALLED.
a™, «™ .AT..
APT,, ,««.» PAr..
Numben.
No*, ud Fica.
Numben.
Not. ud FuM.
L
n.
DL
I.
n.
m.
I.
n.
in.
I.
n.
in.
McP. .
G
H
{
4
7
7
s
7
I
3
3
2
6
2
S
7
4
2
5
2
3
7
5
7
5
3
S
S
1
3
4
5
F
2
Ay
4
4-^
4.7
4-7
2.2
4.3
27
1.8
6
2.7
'7
2.3
AVERAGES.
Numben toA
Kumbcn. Ftcti.
After (even day* 4.3 3.7
After thirteen days 3,2 2.4
are at first a strong aid in retaining nonsense syllables, but in
the course of two and a half months the advantage o( series
varying in this way is lost, because of improvement of the
ordinary series through practice. With words the typograph-
ical variations are of no aid whatever. The meaning variation
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HARFET ANDREW PETERSON.
is far more imporunt and is the kind of variation relied on.
The results have an interesting bearing on the theory of adver-
tising and printing. Our own conclusion is that if typc^raph-
ical variations have any value here for memory they must offer
a constant novelty. Mere variation without a very consider-
able amount of newness is of no aid. If there is to be simply
change from one familiar variation (or even new combination
of familiar variations) to another, then the variation in the
sense is the more attractive and influential, in fact the only
thing that is influential. This may Ux the printer rather
severely, but it is some encouragement to those who depend
on the content of their advertisements, rather than on the form.
When mechanical variations are left and the attempt is made
to secure variety through meaning, the first part of our results
are positive, the second part indecisive. Sentences are as well
remembered as words, when the learning time is long enough
to comprehend both. Binet and Henri and others had already
shown this, but our lists of words and corresponding sentences
were much longer than theirs. A still further increase in the
length of the selections would without doubt show the same
result. The negative results of our experiments vrith numbers
and biographical facts are to be interpreted as a superiority of
preformed associations over associations required to be formed
during the learning process. In the series of numbers without
facts the subjects could not prevent the numbers from suggest-
ing associations from their past experiences. 57 became 57th
St., 65 the age of a member of the family, etc. Dates, too,
were suggested by some of the numbers. The impossibility of
controlling the associations led to the discontinuance of the use
of numbers. A similar difficulty has been mentioned already
in connection with the use of lists of words.
In the next section we propose to make a brief digression to
discuss a question of nonsense syllable technique. It may be
omitted without detriment to the comprehension of the main
problems under consideration.
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INFUJENCE OF COUPLEXITr AND DISSIMILARITr ON MEMORT, 25
IV. ON METHODS OF LEARNING AND TESTING NONSENSE
SYLLABLES.
The method of learning the series of nonsense syllables in
III consisted in giving the various series to be compared equal
numbers of repetitions, extending the learning process over two
days, and securing an immediate recall on the first day and a
recall after 24 hours on the third day. On the first day the
subject was given 2 repetitions of a series in practically imme-
diate succession and then tested for immediate recall, the test
being the quantity of syllables recalled and the cue, simply the
direction to begin. This was followed by 5 repetitions. The
next day the subject spent from 5 to 10 minutes, the exact
amount determined by the operator and depending on the
number of series, in recalling, as before, as many syllables as
he could. Placing in the proper series was understood «> be
not essential. This was followed by 3 repetitions. On the
third day without further seeing the series and with no other
cue than an enumeration by the operator of the varieties of
series which had been given, the subject again wrote as many
syllables as he could recall. There was no time Hmit on this
test. TTie intervals between repetitions and series were prop-
erly regulated, and kept constant. Reviewing was permitted
during the progress of a repetition but not between repetitions.
The rate was 50 beats of the metronome per minute with an
exposure on every alternate beat. The large percentages of
recall in the tables speak in favor of the workableness of the
method.
The method has advantages over several of those currently
in use. In the Ebbinghaus method of entire learning and re-
learning, if the series are short, for example nine syllables, the
repetition is too gross a measure to detect small differences.
The difference of i repetition between the 4 and the 5 (let us
say) necessary for perfect immediate recall of two nine-syllable
series may represent the recovery of a single consonant, or
18 seconds of hard work on the part of the subject. Our
method gets over this difficulty by giving a fixed number of
repetitions, the same for the various types to be compared and
Digilizcd by Google
26 HARVSr ANDREW PETERSON.
measures the difference by the percentases of recall. The
method of successes, used by Miiller and Pilzecker and many
others, also has this advantage, but has one objection that in
our opinion is fatal to it for many subjects, in fact most sub-
jects. It encourages word associations. The two syllables
constituting a couplet are likely to suggest to a subject single
words or phrases which form a unity in his past experience and
serve here to link the two syllables together. Qan muc sug-
gests gander mud, laj gul suggests large girl. The difficulty
is a well-known one and is treated by Ebbinghaus in his Gnind-
ziige, p. 676. It is present to some extent in the non-couplet
methods, but the couplet methods (TrelFermethoden) greatly
increase the frequency of occurrence. In an investigation
made some years ago it was demonstrated that couplets in
which word associations of this sort occurred were better
retained than the rest of the series, and the superiority was
measured.' Under certain conditions, which do not concern us
here since they were the same for both kinds of material,
couplets in which word associations did not occur had a recall
of 63 per cent correct after one day, which sank to 19 per cent
after fifteen days more. In contrast with this, couplets in which
word associations occurred had a recall of 82 per cent correct
after one day, which sank only to 64 per cent after fifteen days
more. The results were based on six subjects and 64 couplets
altogether, of which somewhat the larger share were couplets
in which no word associations occurred. If the couplets in
which word associations occurred were thrown out or separated,
there would be no objection to this method, but the waste of
effort is great, and it has never been done to the writer's knowl-
edge, except in the investigation just quoted.
Our method makes an economical use of the experimenter's
and the subject's time by using short series and distributing the
learning over two days. By making the amount recalled,
instead of the number of repetitions required to learn, the
means of measurement, it measures small differences. It keeps
the word association factor at a minimum. If it has an objec-
' Peterson, H. A. Recall of Words, Objecis and Movements. Psych. Rev.,
1903, Mon. Sup., iv, p. 231.
Digilizcd by Google
INFLUENCE OF COUPLEXITr AND DlSSIMILARITr ON MEMORT. 17
tion, it is the possibility that the recall after the last twenty-
four hours may not be enough for purposes of comparison.
This is doubtless true of some subjects. In the foregoing experi-
ments, P was such a subject. This objection would not hold
for the five other subjects employed by us, with all of whom
the recall was sufficient for comparison.
V. EXPERIMENTS WITH PLANE AREAS
I. Adding yartations to a Material Containing Little
Van at ion
The next material selected was both simple and highly sim-
ilar internally. Different shades of gray were associated with
their spatial positions on a cardboard area. Four series were
given, the first of which varied in shades of gray only, the
second in gray and the color of the center, the third in gray
and the size of the different presentations of the series, and the
fourth in gray and the shape of the presentations. The same
seven grays were used in all four series. They were the Her-
ing papers Nos. i, 2, 5, 8, 19, 35 and 49. Each series had seven
terms or presentations in it, and the shades of gray ranged
from black to white with about equal differences between
nearest shades. All seven terms were exposed simultaneously.
The gray sizes may be given as a sample series. They were,
from left to right as follows:
Oblongs, Kei^t twice (he width. Dark gray 128 sq. cm.; very light gray,
40.5 >q. cm.; white, 60.5 iq. cm.i bliclc, 2 sq. cm.; medium gray, 84.5 sq. cm.;
light gray, 8 sq. cm.; veiy dark gray, 24.5 sq. cm.
The form-vatying series is shown tn the plates in the Appen-
dix.' All of the series except the one which varied in size were
composed of terms whose areas were 50 sq. cm., and even the
size series had the same total area as the other three, viz: 350
sq. cm. The color-varying series were made by pasting small
oblongs of color 1.5 cm. wide and 3 cm. high on the gray
oblongs, themselves 5 cm. wide and lo cm. high. Each of the
series was mounted on a sheet of white cardboard 22 X 28
inches, with the longer side as the base.
' Gray Forms.
Digilizcd by Google
28 HARFEr ANDREW PETERSON.
Conceivably the ease of memorizing such series would depend
greatly on the order o( succession of the terms. However,
inasmuch as one of the purposes of the investigation was to
obtain information on this point, aside from certain obviously
easy arrangements, it was thought best to determine it by
chance. The following cases embrace all exclusions: (i) in
sizes, a continuous increase followed by a continuous decrease,
or vice versa; or a condnouus increase alone or decrease alone;
(2) in shades of gray, or violet (the latter series to be described
later) a continuous change from black to white or vice versa,
or from red to purple or vice versa; (3) in grays, colors, and
sizes, the same arrangement as some previous series. This
rule resulted probably in less uniformity of material, but at least
was free from the influence of unconscious subjective favoring.
To increase the number of series a group of four series was
next made which in all respects was similar to the gray group
except that shades and tints of violet were used. The colors
in the series with colored centers, and the shapes in the form-
varying series were different from what had been used in the
gray group. The shapes are given in the plates. The same
sizes were used in the size-varying series as in the grays, but
to diminish interference from the gray sizes they were right
triangles. Tlie effort was made to secure violets which would
be about as difficult to discriminate as the grays. The ones ,
selected were: blue violet, violet, violet tint i, red violet, red
violet tint i, violet red. To these purple was added. The
grays were learned the first week and the violets the second week.
The method of learning the series was the same as the one
used in experiments with numbers and biographical facts. We
shall describe the process in its several steps. When the shutter
opened the subject began to learn the series. As soon as he
thought he had mastered it, so that he could give it the next
day, he gave a signal, whereuf>on the shutter closed. The
subject then turned to a small table on his right, uncovered a
set of unmounted duplicates of the series, and tried to arrange
them in the right order. As soon as he had arranged the
series as best he could he gave a signal, whereupon theoperator
at once removed the duplicates. If the attempt was unsuc-
Digilizcd by Google
INFLUENCE OF COUPLEXITr AND DISSIMILARITT ON MBiiOST. 29
cessfui, the duplicates were returned bunched and covered, the
series was again exposed and the teaming process resumed, and
again tested, rill the series had been perfectly arranged. The
lengths of exposure were kept with a stop-watch.
Where more than one exposure of the series a day was neces-
saty, the lengths of the exposures were recorded separately,
and the number of arrangements which the subject required.
The next day the series given on tlie previous day were tested
again by use of the duplicates. If the arrangement of any
series contained an error, that series was again exposed for
such a length of rime as the subject required, and again tested.
llie subject could not omit the arranging if he desired. If he
showed by his preliminary arrangement on the second day that
he had held the series perfectly for a day, it was not again shown.
Having been brought up to the standard, the series was dropped
for thirteen days, when the retention test took place. The
learning was usually completed by the third day. Tlie pur-
pose of all this was to bring the series up to a point of imme-
diate fixation that would insure enough recall after two weeks
for purposes of comparing the different types of series. The
test which was given after thirteen days consisted in the sub-
ject's again arranging the series. No introspections were
allowed and no comments could be given dll after this test,
because such introspections or comments would fixate the
senes, and do it unevenly. For introspections our main reliance
was on series given especially for this purpose and not recorded
in the tables. Reviewing after an arrangement had been made
was not allowed. Having arranged the duplicates the subject
who followed instructions dismissed the series from his mind.
The intervals between exposures and between series were regu-
lated.
Toward the end of the invesrigarion a series of experiments
was carried out upon the same subjects with similar material
for the purpose of determining the value of the pracrice of
allowing the subject to arrange. The details are given on pp.
65-7, which may be profitably read at this pwint. The method
employed consisted in giving parallel series as nearly equal in
difficulty as possible. In one-half of them the learning was
Digilizcd by Google
30 HAItFEr ANDREW PETERSON.
carried on solely by looking at the series through the aperture.
The other half were given the same lengths of exposure and in
addition the subject was allowed the usual arrangement of
duplicates. The recall after the lapse of a week gave the rela-
tive efficiency of the two methods of learning, and by sub-
tracting the toul recall of all the series in which there was no
arranging from the total recall of the series in which arranging
had been allowed, the value of the arrangements alone was
obtained. Since a given number of arrangements produced a
certain. number of units of recall and a given amount of time
of exposure produced a certain number o( units of recall, by
reducing both to the amounts of each necessary to produce one
unit of recall it was possible to hnd for an arrangement its
equivalent in minutes and seconds of learning time. With this
average value, one for each subject, the arrangements were
converted into learning time and added to the amounts actually
consumed by a subject in looking at the series through the
aperture. Thus our two time measurements were reduced to
one.
This in brief was our method. In one way it lacked exact-
ness, namely, in the distribution of the learning periods over
varying numbers of days. But in another way it had exactness.
By making the subject the judge of the time necessary for
learning, learning times were secured which minute for minute
represented equivalent degrees of effort. A comparison of the
subjects' speed of learning given on page 64 will convince any
one of the impossibility of getting accurate results when giving
the same exposure intervals to all subjects and for all materials.
The difficulty of appraising the value of the tests allowed the
subjects during learning — a difficulty which has been felt by
many experimenters on memory — ^was satisfactorily solved by
the method described. Again, one of the principal advanrages
of our method is the opportunity it affords for studying different
types of learners. The fact that one series was learned more
thoroughly than another, that the subject could not judge
accurately his ability to hold a series for a day, did not introduce
error into the results if the assumption be granted that recall
after thirteen days is in proportion to the thoroughness of the
Digilizcd by Google
INFLUENCE OF COUPLBXlTr AND DISStMILAXITr ON MEUORr. 3 1
original mastery. Any one who doubts this can find evidence
in our tables in the form of mean variations.
The use of duplicates as a means of testing was adopted to
avoid as far as possible the inequalities which would be intro-
duced into the material by the ready presence or absence of
names. Lehmann' and Angell,' among others, have shown
that colors which can be readily named are better discrimi-
nated and remembered than those which cannot be. Again,
the desire of the author was to guide the whole investigation
away from language and into retention and learning of the
material presented. The initials of the colors could be made
into a mnemonic word and thus remembered, and similarly
sizes and forms. There was no desire to experiment in the
linguistic field here, and the subjects were repeatedly turned
in the opposite direction and, judging by their own testimony,
with success. The part played by language is discussed on
p. 47 in connection with methods of learning.
The results of the gray and violet sets are given in Table 3.
The learning rimes are given in minutes and seconds and
arrangements; for instance, F. learned the grays in 4 mins.
I sec. and 2 arrangements. The abbreviation 'arrs.' means
number of arrangements which the subject required in bringing
the series up to standard. The recall in the second half of the
table is based on a method of scoring which briefly was this.
Perfect score for a series: 14. Each term allowed i for correct
absolute position (left end, or second from there, etc.) and i
for correct relative position (having the correct terms on both
sides of it). One-half for next-to-correct absolute position,
e. g., 4th or 6th from left end instead of 5th. One-half for
one neighbor correct, and one-quarter for each neighbor cor-
rect but on the wrong side. Terms whose relative positions
are made incorrect by the errors of the other terms lose no
credit themselves.
The table shows that when the shades of gray and violet are
varied in form and size, or when they are given colored centers,
there is a marked reduction in the learning times and a large
■ Phil. Studien, V, 1S89, p. 96.
' Phil. Studien, XIX, 1901, p. 1
Digilizcd by Google
HARFEr ANDK£W PETERSON.
Table 3. Atioi variti in Color, Sixt and Form.
A, Ltaming Timet.
CIUT..
a.ro««.
COi.O.>*T..
Tune.
Am.
Time.
Am.
Tinw.
Am.
TiiM.
Am.
01
2
I
2
3
S
' '
+1
30
43
II
3
I
12
03
38
3:30
2 :OI
2:15
2 :20
I
L.:;:::::::::::::::::
Av
3 "'"
4-5
,-..
2.17
4
2 : 12
2.67
'
vo.«..
». rouit.
.„.„.
C. TIOLm.
F
3
1
4
2
6
4
4
I :3o
I :45
I 123
I :oS
1 :5'^
2 :22
Mc.P
G
s
4
45
S'
41
43
54
35
39
47
19
09
13
4
4
H
2
1 ""::::
6
"
7 ."
5.33
■ j5
!.67
3-33
' -39
3-33
■
B. Recall after Thirteen Days.
o„„.
noun
a.,<,««
,.ro«..
o...„.
,.m..
CMt.
„r„.
F
6.50
4.00
4.00
6.00
6.00
8-75
4.00
9.00
7.00
11.50
6.00
11,50
14.00
4.00
:4.oo
6.2s
4.00
4.00
4.00
6.50
6.00
4.00
n.50
8.50
4-00
4.00
6.50
14.00
9.00
4.00
10.50
4.00
4 75
Mc.P
G
4.00 6.50
500 1 4 00
4.00 1 9.00
I
i
( m 1 c ni
7.71
12.25
6.04
6.17
7.42
7-71
* ^
J f
increase in recall. If the arrangements be converted into learn-
ing times, and an average be taken of the gray and violet sets
together, the addition of a form variation reduces ike learning
time 68 per cent and increases the recall 75 per cent. The adii-
Digilizcd by Google
INFIMENCE OF COMPLEXITT AND DtSSIMILAEITT ON MEMORT. 33
tion of a variation in size reduces the learning time about 50 per
cent and increases the recall 7 per cent. The addition of a
variation in color reduces the learning time ^5 per cent and
increases the recall 32 per cent. Form is therefore the most
effective variation, color next and size the least. All six sub-
jects benefit by all three variations. The improvement is
extremely marked and very general.
The question arises whether the variations in color, form
and size were not easier to associate with position than the
grays and violets, and were therefore taken as the thing to be
learned, the grays and violets being neglected. In other words,
was the improvement due to substitution rather than to
increasing complexity ? Did the subjects use the shades of
gray and the violet colors at all ? The likelihood that this did
occur is increased by the fact that interference was likely to
enter from the connection of the same shades of gray with
different positions in different series, and the same for violets.
The opinion of the subjects on this point is of value. They
said that the grays (or violets) and their added variations
formed unities before the learning process was completed, but
that the variations added to the grays or violets, being the more
easily discriminated, were the main reliance in learning and
recalling.
The experiment does not tell us whether the combination of
two variations, in themselves about equal in discriminability,
would be more readily associated and better retained than either
alone. For example, the table shows that shades of gray and
violet colors without additional variations were about equal.
Would their combination result in a learning time and retention
better than either alone ? While the experiment was not per-
formed, there is no doubt that at this low level of variation it
would.
To summarize the present situation in the solution of our
problem: in the shades of gray or shades and tints of one color,
a material has been found which has a rather large amount of
sameness and simplicity about it, and still is free from the
preformed associations which hindered the linguistic experi-
ments. So far as this material is concerned the experiments
Digilizcd by Google
34 HAXFEY ANDREH' PETERSON.
just completed answer the first part of our thesis. Adding
variations improves both the learning times and retention of all
the subjects by targe amounts, the precise amount differing with
different variations. The next step is to try adding variations
to materials similar in their general character to grays and
violets, but containing in themselves more variety and com-
plexly.
z. Adding Variations to More Varied Materials.
In this set of experiments there was not only an ascent to
more varied bases than grays and violets, but there was also
an effort to add variations that were equal or less in discrimi-
nability than the bases to which they wereadded. Color,form
and size were suspected of fulfilling these conditions. Twenty-
four series of six different kinds were made.
i 4 series of colore iv 4 series of colored sizes
ii 4 series of sizes v 4 series of ndored forms
iii 4 series of fonns vi 4 series of colored forms of
difierent sizes.*
The twelve series on the left aim to find the value of color,
size and form separately; the twelve on the right, rfieirvalue in
combination. Together they should answer such questions as
the following: Suppose it should result diat colors and sizes
each by themselves are learned about equally well. Are series
which vary in both ways simultaneously (colored sizes) learned
more quickly, and retained better, or not ? If better, it can be
due only to the increase in complexity and resulting differ-
entiation, and not to substitution. In the same way the last
two groups on the right may be compared with the last on llie
left.
The general plan of these series differed from that of the
series of grays and violets in one important respect. The col-
ored sizes, for example, did not add a size variation to the colors
of the previous color series, but, as far as the realm of colors
* It will be found helpful in the comprehension of the following general
description to read for illustrative purposes the construction of a few typical
series in the Appendix, pp. 74-80. The Bradley papers were used.
dbyGoOgk
i\
INFLUENCE OF COMPLEXlTr AND DlSSlMlLARJTr ON MEMORT. 35
offered variety, combined size with colors not heretofore used.
Similarly when in the third, fifth and sixth groups of series
above enumerated, form became a base, the same forms were
not used over again, as was the case with the shades of gray
and violet, but new forms were found. This change was in
the interest of a reduction of interference. The principle could
be carried out most fully in the case of forms, less completely with
colors, and still less with sizes. Our guiding idea was to use
all the wealth of variety which each realm, color, size and
form afforded. Our attitude was therefore an entirely prac-
tical one. Of the 76 different colors used in this set and in the
gray and violet sets, 38 were used only once, 18 twice, 14 three
times and 6 four times. Of course the subjects did not dis-
criminate in memory nearly as many colors. Of the 78 differ-
ent shapes used in the investigation vrith these subjects, 48
were used only once, 26 twice and 4 three times. The repe-
tition of forms was confined entirely to two series in each of the
form-varying groups, namely. Forms I and II, Colored Forms
II and III, Colored Forms of different Sizes III and IV,
and these six series were composed wholly of forms which had
been used once before. Thus there was a restricted area
within which the effect of repeating forms could be observed.
It is essential to note that in respect to this feature the three
form-varying groups were on an equal footing, for otherwise
they could not be compared. Wherever a form was used
again, it was altered markedly in size and color. With series
of sizes the limitations of the apparatus and work-room made
the variety small. In certain extra series not included in the
results we tried the effect of larger sizes, but in the size series
given in the tables the aggregate area of the seven terms of a
series was in every case 350 sq. cm., which was the same as
for all the other series. Now within this limit the numberof
sizes which are favorable for inter-term discrimination is rela-
tively very small. We found the best showing for sizes could
be made by restricting the choice to about twelve sizes, which
we did. The other devices used for reducing interference were
to give each series which did not vary in form or color a dis-
tinctive color and form of its own; similarly each series of
Digilizcd by Google
36 HARFET ANDREW PETERSON.
colors had a distinctive serles-fomi, etc. The series were
mounted on white cardboard, 14 X 2S inches, all the terms
resting on a horizontal base line. A full description of all the
series used, including some extra ones not reported in the
tables, but used in the analysis of errors to follow later, will
be found on pp. 74-80. A few further remarks here will give
a sufficient account of the series for most purposes.
As it was the intention to compare the results of pure sizes
and colored sizes it was necessary to keep them equally dis-
criminable in size. This was done by using the same sizes
(though not in the same shapes) in both. Thus two series of
pure sizes and two of colored sizes increased in area in the
geometrical ratio of 2.77 beginning with a minimum area of
.5 sq. cm. The other two series of sizes varied by irregular
ratios which decreased somewhat toward the largest terms, but
they were repeated in the other two series of colored sizes.
The order in which the terms of the series were arranged was
determined by chance, excluding the exceptions made on p.
28. The twelve series varying in form are reproduced in the
plates on a reduced scale and need little further description.
All of the forms in the third and fifth types were of the same
area, 50 sq. cm. The guiding ideas in die selection of forms
were to keep within the three classes: conventional geometrical
figures, very simple decorative designs, and relatively meaning-
less forms. The word relatively is emphasized, for those
subjects who looked for meaning in forms usually found it, —
meaning of some sort. The forms vary from simple to some-
what complex, but there are no intricate forms. Considerable
care was taken to make the series as nearly equal in difficulty
as possible, with what success will appear in the sequel.
These twenty-four series were given in the same way as the
gray and violet sets. The subjects worked on three, and if
necessary to learn the series four, successive days each week;
on one or two occasions, five days. To distribute tne effects
of practice and interference, toe six types were learned con-
currently, although the Roman numerals I, II, III and IV do
not indicate the order in which the series were learned. All
the conditions not specifically mentioned were the same as in
the gray and violet sets.
Digilizcd by Google
INFLUENCE OF COMPLEXtTT AND DISSIUILARlTr ON MEMORr. 37
Tablb 4. Artas varttd in Color, Shu and Form. Associalti with
Spotted Position.
A. LEARNING TIMES.
..
„.
....
.V.
AV.^0...
Tune.
Atn.
Time.
Am.
Time.
Am.
Tune.
Am.
Timt.
Am.
G
H
I::::::.
N
R
SI
:14
=39
44
IM4
4>
2
Z
4
3
^35
4"
1:2s
■'5
=38
:30
:5>
■43
1:02
:i4
.19
4
1:29
1:02
r29
3-75
3-«>
3 25
3 25
3-2S
3 as
Av
:S«
3"7
-45
2.50
^59
4-33
:38
3 17
■SO
329
G .
H...
J....
L
N...
R....
G...
H...
J....
V
4-
3'
,1-
12
V
♦S
1-
40
24
6.
3-
367
467 45
4.83
29
2.
■vi
w
38
18
2.83
d
^eJ Shei.
G
■■*!•
=34
2
=23
4 ,
»5
8
4=
4 50
m
40
2
:29
4 I
12
50
4.00
[:;.;;::
2»5
=39
2
■45
2 1
33
4 I
S.oo
1:23
■40
4
i»4
5'
4
4.25
:«
:t1
2
:"5
26
5
1"
3.75
^59
35
4
:■?
■7
4
32
425
Ay
7'
4
■36
2.67
^32
4
54
SI7
48
39^
DiBiiizcdb, Google
RARFEr ANDSEW PETERSON.
Cotortd Forms.
•
.„„™.
Time.
Am.
■^-
Am.
■nme.
Am.
Time.
Am.
Time.
Am.
G
H
J
L
N
R
■■'S
3
2
3
:I9
7:15
M
:i3
:"3
33
37
4
:2S
:22
:22
^38
■■•s
■•s
25
26
45
39
■S
14
3.00
2 75
2 75
2.50
2.25
«.'5
A.
:26
J.33
:3»
2.50
'1
2.67
■^3
'.83
:=7
2.58
Coiored Formt of Digmnt Sixes.
G
■20
:il
4'
43
2
29
2.00
H
4*
2
46
^
30
41
2.00
J
m
2
:.34
38
40
2.50
L
;28
2
■52
■■V>
35
36
2.50
N
:20
2
:l6
:25
■5
19
2.(0
R
:i6
«
fi6
:i4
'
«4
«5
2.50
Av
129
2
■36
2.67
:3^
= ■33
»9
2.3^
31
233
Recln.
RcuU.
ReciU.
Rcc^U.
AOII.
ReealL
5 25
It
4.50
6.00
5-50
11.50
8.00
6.75
7.00
14,-00
8.15
7.00
♦ SO
4.50
6,7s
7.50
8.00
8.50
7.25
6.00
6.00
4.00
6-75
H
6 Si
6.31
t :;::::::::;:::;:::::::
N
7.88
7->3
6-13
9- as
6.38
6.41
705
7.00
14.00
4,00
11.50
5.25
5.00
6.00
6.50
4- SO
4-00
8.00
4.50
4.00
11.50
5.25
8.2s
6.50
7.00
4.00
6.63
9.81
H
i :::::;;;:;:::;:;:;:;:
8'3
531
4 25
N ....
Av
7-79
5.00
6.92
7.08
6.70
„Go(ij(lc
INFLUENCE OF COMPLEXITT AND DlSStUILAMlTT ON UEMOHr. 39
itJk
R«cJL
HwJL
If.
RuiO.
ACE*.
ReciD.
11.50
14-00
II. so
11.50
4.00
8.00
+ .00
6.7s
7.00
5.00
6.75
525
il.So
lo.so
6.00
8.50
11.50
11.50
9.00
11.50
8.00
7.69
9.69
9 63
9-31
10,13
J
L
N..
Av
11.38
5 79
8.33
,0.00
s n
G.
5.00
6.50
11.50
5.00
4.00
8..5
4.00
6.50
S«5
8..S
9!S
6.00
(,.%$
5-5»
4.00
8.50
10.00
10.50
14.00
8.50
4.00
10.50
6.00
6.38
H
1
8 00
L.
4.56
7.81
8.38
N
«....
A.....
6.71
6.46
6,7.
8.92
7.20
Colortd Formt.
Colored Forms of Different Siti
a..
8.00
l+.OO
7-So
4.00
11 50
14.00
6.50
14.00
■4.00
6.25
14.00
5 50
5.00
6.75
5-5»
5-75
6.00
9.00
*-75
10.50
6.25
7.00
10.50
14.00
H. .
11.31
8.31
5-7S
10.50
10.63
f-. :::::::::;::::::::::::::
«...
''- .
983
10.04
'33
8.83
8.76
9.00
10.50
9.00
9.CX)
11.50
4-75
8.50
14.00
11.50
5-75
5.00
14.00
10.50
4.00
10.50
11.50
+■'5
4.00
6.75
6.25
10.00
6.50
7.00
9.25
9.81
7.69
S St
8.63
9-SO
8.25
10.08
6.29
8.53
DiBiiizcdb, Google
HARrsr ANDREW PETERSON
Table 5. Artas varied in Color, Siv anJ Form
Recall per Ten Seconds.
COLOM.
■nit.
Fomui.
COL. (IZII.
COL. roui*.
c. r. d. a.
Rec
M.V.
Km.
M.V.
R=.
M.V.
Rec
M.V.
«.
M.V.
Rec
M.V.
I.
7'J
■Ifl*
1.060
.OS2
IIW
..08.
■7';7
.258
2.,,,
.70^.ooo|i.3.2
I-H7
.86,
.w
.7»(
..„.
.Q0<
.10^2,2+1
■ m-
].«.
.249
1. 167
.„(
Tt
.108
!..77
.064
■■w
.,80
■Q+3
.70s
..619
.049
1.700
.217
'■7V
.630
1.297
..84
.0.5
1.05s
59^
.675
.013
Av..
■ ♦83
54°
.....
■3.6
J. .13
.66s
..0,5
..^
1.6»8
.6,J..688
.656
I.
.7.8
..04
2.762
..28,
2-23,3
.56,
.600
.202
2.369
.486
1.444
i.S
11.
...6-
■142
..w
..3S
..07i
■591
.85?
.04E
2. 306
1.20.
..27
111.
.68,
.17
...66
.31.
.960
.7o<
.797
.00'
..,8)
.497
.938
.609
.722
■637
.840
2.4..
.742
.959
..57
..47J
.4.3
■73.
■S9l>
A».
.822
.7.
..477
643
..669
.653
.802
..03
..883
.4Ss|..329
.362
1.
.4.2
.So^
.076
.982
.46
.S4,
.062
.846
,036 .924
.07s
11.
.62s
..4t
.267
..6,
.509
.6.(
.?«'
■ 17c
.70<
.050 .891
.108
.39;
■63;
..620
.492
.62c
.016
.682
.128.. 35:
3S4
.690
.21^
354
.24
..402
■274
.47a
.32
■«3
.43 827
.72
Av.
■477
..8.
.430
..00
...28
.383
.604
■ 997
.8.0
089 .999
■.77
I.
.634
.029
..643
(3.
.949
.322
.406
■"S7
.727
164
..87s
S«3
,86,
.201
I..2S
■302
.6s(
■.9-
.962
.07.
..S9i
243
■S«
..6.
.9.C
..9-
.■960
.33-
.3S.
..12
1*1
04s
.8o<
SS2
.652
.0..
783
.329
.■47i
..51
.440
■023
..029
..38
.136
Av.
.663
.10.
....2
.266
.627
DiBiiizcdbjGoogle
INFLUENCE OF COMPLEXITT AND DtSSlUILdRITr ON MEUORr. 4.1
, 8^ -627
i.i6ji .064
.08^1.402! .87s .394I
;|i.289
1-30+
'97
.5841.
4|i .037 1 ,
2.013 '74
71311.13411.413 .416
' ... . -428
2.64d .0662.519 .680
C»LO„.
■ou.
.^.
Rec
M.V.
Rec.
M.V.
R«.
M.V.
■f3
.822
.477
.»3
1. 115
1-19+
■5+0
.347
.168
'-477
■430
'■*^^
.815
.316
■643
.100
.266
.120
2.,.3
1.669
1. 128
1.627
2.277
1.413
.665
'53
1.383
.327
Sio
H
1.
L....::::;";"
N.. .
3«
Av
■9S9
■IS'
■904
.296
1.70s
.«97
.«.™^
„.,.^
c. r.d. ^
Rec
M.V.
Rm.
M.V.
Rk.
M.V.
C...
1.015
.802
.604
.463
1.046
1.153
.190
.103
097
.096
.326
.210
1.648
1.883
.810
.891
2.579
2.876
.649
.105
.723
.679
1.6S8
1.329
.999
1.352
•839
2.292
.625
.362
.'77
.384
427
.996
H
I
t
N
R...
847
.170
1.78,
.450
■583
■495
DiBiiizcdb, Google
43 HARFEr ANDREW PETERSON.
The results are given in Tables 4 and 5, In part A of Table
4 the learning times are given in minutes and seconds, and
arrangements; in part B the amounts recalled after thirteen
days are given on the scale of 14 for perfect recall of the series.'
In Table 5 the recall of Table 4 is recalculated by finding the
equivalents, in learning times, of the arrangements, adding
them to the net learning times, and then calculating the amounts
recalled per ten seconds of aggregate learning time. A sum-
mary of Table 5 follows it, and a verbal summary is given last.
"Rec." means recall and M. V., mean variation.
Summary of results. For reasons evident in what follows it
will be necessary to consider the subjects individually. It
may be well to recall the fact that we are seeking limits to the
effectiveness of increasing variety, the combination being each
time new, and that from the very nature of attention limits
will certainly be reached. It may be well to recall also that
with the less varied bases — the shades of gray and violet — all
of the subjects profited very markedly by all of the added
variations. But color is a more varied base than gray or
violets and, to say nothing of isolated series, a dozen series of
forms contains more variety than a dozen series of colors.
Accordingly it may be expected that before long the subjects,
according to their powers of discrimination, retendveness, and
span of consciousness and consequent ability to resist distrac-
tion, will begin to diverge. Some will reach a limit sooner than
others. Under such conditions, averages of different subjects
are worth little. In what follows it will be necessary to con-
sider the memory for size and color separately as well as in
combination. Two very important results shown by all the
subjects in marked degree may be mentioned first, however.
First, all six subjects retain forms muck better than sizes and
colors. Secondly, all six subjects retain colored forms better than
colors. The second of these two results is comparable to the
results obtained in the gray and violet set, for in both cases
the variations added were much more easily discriminated than
the bases to which they were added.
Digilizcd by Google
INFLUENCE OF COMFLBXITr AND DlSSlMILdXlTT ON MEMOSr. 43
Subject G. Pure colors and pure sizes are retained about
equally well. Colored sizes are retained at least no better than
either alone, while colored forms and colored forms varying in
size, in themselves about equal, are not as well retained as
pure forms. G. says :'
Color in colored sizes is a slight aid, but less than the natural fluctuation in
eaM and difficulty in passing from one size series to another. In the form-
vaiying series, in the long run color is of no value, unless there arc no peculi-
arities in torn or size sufficient to hold the series. This seldom happens.
The size variation in colored foims of diffcTcnt sizes may be of value
Subject H. Pure sizes are better retained than pure colors.
Colored sizes show no improvement over even the poorer of
the two. Colored forms are slightly better retained than pure
forms, but the series with two additions (color and size) are
not as well retained as pure forms. H. says: "Colored sizes
are easier to learn than either sizes or colors, but variations
added to form are a distraction in learning. However, in
recall they may confirm the arrangement after it is made."
H.'s learning times in Table 4 do not confirm his remarks as to
the greater ease for him of learning colored sizes. They took
more time.
Subject L. Sizes are much better retained than colors. Col-
ored sizes are more poorly retained than either sizes or colors.
If the four series of each kind be arranged in order of increased
retention per ten seconds of total learning time, all four colored
sizes are poorer than even the corresponding color series. Only
one of the former group is as good as any of the latter. Here
the combination is actually poorer than either of the elements.
Colored forms and colored forms of difi^erent sizes are also
not as well retained as pure forms. L. says:
Colored sizes are harder than colors and sizes because of conflicting methods.
In colors I associate (he end and middle colors with their positions, and link
' Tliese opinions of ihe subjects were obtained in all cases after all experi-
menting had been completed. The subjects did not know what any of the
results of the investigation were except what they may have inferred from
observing themselves.
Digilizcd by Google
44 BARyEV ANDRSW PETERSON.
the intermediate ones with them or with each other, depending on the color
associations they offer. In sizes 1 make groups of regularly increasing and
decreasing sizes.' In colored sizes the color distracts me from using my size
method and (he me vaiiadvns, from using the color method. The result is
1 use both. As a rule (brms are easier than colored ibrms. Oeeaiionally color
is an aid, ibr example when the forms are closely similar. The reason for the
difficulty is the same as in colored sizes, namely, conflict of habitual methods.
Whether the addition of both color andsize to form is an aid I am not sure.
Subject N. Colors are much better retained than sizes, —
the reverse of the two preceding subjects. Colored sizes are
retained better than sizes and about the same as colors. Color
alone added to form shows some gain over pure form, but the
large mean variation makes the advantage uncertain. When
both color and size variations are added, the result is no better
than in pure forms. N. says :
The color in colored sizes makes the size stand out, but introduces a conflict
of methods of learning, and resulting distraction. The result is a mixture of
methods. 1 usually use size to fix the largest and smallest ones and color, and
size to fix the intermediate ones. The variations added to form also produced
distraction in learning, the forms affording sufficient variety io themselves.
The eoior anJ lite variationt aJJeJ la formt juit gaoe me more to notice. However,
sometimes color aids in recalling the position of a form.
With the four persons above limits were reached. With
the next two, however, they were not.
Subject y. Colors and sizes are retained about equally well,
and colored sizes are retained considerably better than either.
If the series of each group are arranged in the order of increasing
retention per ten seconds, all of the colored sizes except one
series are better than the corresponding series of colors alone
or sizes alone. In the case excepted the colored sizes are at
least as good. Colored forms and colored forms of different
sizes are not quite as well retained as pure forms, although the
difference is quite sihall. J. says:
The element of color in colored sizes is an aid, — it gives each member in the
•eries an individuality and thus helps to fix it in its ab»dute position; at the
' On the methods of learning pure sizes, see p. 48.
d by Google
INFLUENCE OF COMPLEXITr AND DISSIMILARITT ON UBMORr. 45
tame time it tends to break the 'slcy-line' ichemes.' It is a larger factor than
the natural fluauations in ease and difficulty of different series of pure sizes,
with a few exceptions, tn general all three variations were aids, alone or in
combination: size, because it makes a 'sky-line,'— to which alto forms may
contribute; color because it fixes the center, or a term left out of my series-
Subject R. Colors alone are better retained than sizes alone.
Colored sizes are about the same as colors. Both colored
forms and colored forms of different sizes are considerably
better retained than pure forms. If the series of each group
are arranged in order o( increasing retention per ten seconds,
all the colored forms and all the colored forms of different sizes
exceed the corresponding series of pure forms. There seems
to be no question that the variations added to forms are an
aid to this subject. She says :
The presence of color in colored sizes is an aid because it makes the middle
terms (middle in area) easier to discriminate. It does not prevent the use of
the pure size method (the method used by all the subjects). The addition of
color and size variations to form-varying series helps materially in differentiat-
ing similar forms both in learning and remembering.
Summary: To recapitulate, — four subjects, G, H, L, and N,
show practically no gain in retention in either of the two prin-
cipal types of increased variation used here. In quite a number
of cases the recall is actually poorer with the combination.
The subjects are eidier unaffected by the variations, finding
sufficient variety in the base, or they are distracted by a con-
flict o( methods of teaming which they do not succeed in har-
monizing, or by the presence of variations which they use only
occasionally but cannot help noticing most of the time. In
contrast with them are the subjects f. and R. To them all the
additional variations were an aid subjectively both in learning
and recalling, and the tables quite decidedly bear out their intro-
spections in the case of colored sixes with y. and colored forms
and colored forms of varying sixes in the case of R. That a
type of variation should be an aid to J. and R. and still not
' On the method of learning pure sizes, see p. 48.
Digilizcd by Google
46 HARVET ANDREW PETERSON.
show a gain in their results is possible. It may be too small
to show; or it may cause an unconscious diminution in eflbrt.
ir a conflict of methods exists in colored sizes they have har-
monized it. This is evident from the fact that they use a
combination of both methods, retaining the 'sky-line' scheme,'
and still using color for the terms intermediate in size, or for
a term left out of the size scheme. They are not distracted by
the multiplicity of variations in series of the most varied type.
It is interesting to note that in natural retentiveness and speed
of learning J. and R. represent opposite extremes.'
J. Methods Employed by the Subjects in Learning the Series
Between the 5th and 6th weeks of the regular work series
were given for the sole purpose of studying the subjects'
methods. During this week no other series were given. On
the introspections of these series, and to a less extent on those
given after the final tests of the regular series the following
paragraphs are based. They refer to methods of learning
only. Recall methods were a survival of some of the learning
methods.
Fundamentally, the subjects did not differ in the methods
they employed. Briefly, they all discriminated the terms of a
series from each other, and partly at the same time, partly
afterward, associated them with each other and with their
spatial positions. The less the terms differed from one another
the more necessary it was to differentiate them. In the two
series which varied only in gray and violet, discrimination
overshadowed association, and to the former the long learning
times of those series were due. In series of pure colors and
pure sizes discrimination was easier and briefer, while In the
series in which form variation entered, voluntary discrimination
was at a minimum. It was much more nearly instantaneous
and Involuntary. As one subject put It, 'discrimination was
less necessary, because there was not much likelihood that the
' The meaning of these conflicts of method, etc., will become clear from the
discussion of the next topic.
' See p. 63.
dbyGooQle
INFLUENCE OF COUPLEXITT AND DlSSlUlLARlTr ON MEMORT. +7
terms would be mistaken for one another.' It will be shown
in the analysis of errors that with exceptions this remark was
true. The subjects came to feel automatically on seeing a new
series whether there would be in future much or little liability
of mistaking one term for another, and increased or reduced the
discrimination process accordingly. Except in the grays, vio-
lets, and pure sizes, perceptual discrimination in the simul-
taneous exposure was easy. It was the discrimination in mem-
ory which gave trouble. The other half of the learning process,
the association, consisted in grouping the terms of a series.
They might be grouped either because they were adjacent
(contiguity), or because they were similar. Discrimination
itself was likely to have impressed similarities, because it was
similarity that provoked discrimination. The grounds of classi-
fication presented an ever-changing variety. A few of the most
common will be mentioned in connection with the particular
types of series, to which we pass after a word on the subject of
language.
Language played small part in learning and retaining the
series. Several subjects said that when the forms and colors
were quite familiar they were apt to suggest names, and one
said that sizes were thought of by the numbers i to 7, but that
the numbers were not run together at all. This was the sub-
ject R. Not a single subject reconstructed the series from
language cues, according to testimony taken at the close of
the investigation.
Colors. The ends and the middle were conspicuous posi-
tions with all the subjects. They looked to see what was there,
and if a striking color was in any one of them it was likely to
be made the basis of a contiguity group or at least make the
association of the term with its place easier. Other con-
tiguity groups are illustrated by the introspections: 'Red and
green are complementary and in 5th and 6th positions,' 'blue
green is a familiar phrase and blue is on the left of green here.'
Some of the similarity classifications which united non-contigu-
ous terms were: 'The bright and the relatively colorless or
dead ones,' 'the heavy and the light ones,' 'the violet pair,'
the 'reddish ones,' 'colors on the border-Hne between the
Digilizcd by Google
48 HARFET ANDREW PETERSON.
seven spectral colors.' There was no hesitation in classing a
blue green or a green blue, or even die lighter tint of blue as a
blue in one series and a green in another according to the
exigencies of the situation. // is significant that the recogni-
tion of several colors, or sizes, or forms for that matter, as similar
was both an aid and a risk, — the latter because it opened the way to
subsequent confusion of the positions of the similar terms. Two
'blue' colors or two 'low' forms were peculiarly liable to exchange
of positions. The corrective was of course further discrimina-
tion. The number of groups in a color series was necessarily
relatively large, because the series were constructed so as to give
as much variety as was compatible with keeping inter-series
interference at a minimum. This number varied from three
to five.
SiT^s. When in one series the 3d and 5th in size were next
to each other, in another the 3d and 7th, and in another the
istand 7th, and since six such series had been learned before the
first two came up for final test, contiguity could not hope to
prove a successful method of learning sizes, and was only
rarely employed. Similarity was not used extensively if we
exclude such contrasts as smallest and largest), because it led to
the confusion mentioned in the case of similar colors. All of
the subjects employed the same method. They grouped
together a number of terms, often not contiguous, which formed,
abstracting from the intermediaries, a continuous increase or
decrease in size. A variation of the same method consisted in
remembering the length, direction and position of the lines
running through the tops of the groups. These lines were
called 'sky-lines.' Some of these 'systems' or schemes were
simple and natural, others complicated and natural, and quite
a number both complicated and forced. By forced is meant
not true without exceptions so numerous that the value of the
scheme must have been shght. Several illustrations of the
method may be given.
Sizes B. The correct order was 3416275.' The subject's
system was an ascending 'sky-hne' from ist to 6th places, the
* The numben denote the relative size of the tenni,i representingthe smallest.
Digilizcd by Google
INFLUENCE OF COHiPLBXJTT AND DISSlUtLJRITr ON MEMOKT. 49
smallest and next smallest forming a second ascending series
interpolated in the first at the 3d and 5th positions. The last
term stood apart.
Sizes A. The correct order was 5416372. The subject's
system consisted of three 'sky-lines:' 541, 167 and 132.
One additional instance is given to illustrate the fact that
subjects are not likely to hit upon the same scheme, unless it
is very obvious.
A series of circles varying in size and shade or tint of red and
arranged in the order 3261547 was given. One subject ob-
served that the smallest was in the middle and the largest on
the right end, that there were two pairs which decreased in
size to the right (32 and 54), that 4 was nearest in shade to 7,
and that the next largest was on the left of the middle. The
second subject agreed with the first, as to the smallest and
largest, but his further grouping was 321 and 654, in which two
groups the direction and rate of decrease was the same, or was
taken to be. The third subject made a rightwardly ascending
group out of 147, a rightwardly descending group of 32, while
6 was discriminated from, and thereby associated with, 4 which
it resembled in color. The fourth subject thought this series
was easy for sizes, an opinion which the other subjects did
not share. For her the middle one was the smallest, while
each wing consisted, in order from left to right, of a medium,
a small and a big one, with the larger three on the right. 2
was discriminated from possible rivals by its color, and 6 was
the one nearest 7 in color.
It becomes evident that the schemes varied greatly in effect-
iveness. In the third illustration the one used by the last sub-
ject was extremely good, while that used by the third subject
was poor. This fluctuation in the simplicity and naturalness
of the systems explains the large variations in the retention of
certain series of pure sizes and colored sizes as compared with
the remaining series of the same types with the same person.
For example, the unusually larger retention of Sizes I with
certain persons was due to the discovery of the grouping 45,
12, 67, 3.
In the colored sizes the variation in color made the size
Digilizcd by Google
50 HARVET ANDREW PETERSON.
Stand out but it also tended to check and break up the size
schemes. The result was a mixture of the two methods, the
superiority of which to either system alone the subjects were
not agreed upoot according to their testimony quoted in the
verbal summary of the last table.
Forms. Here again the subjects agreed in their methods, and
it was substantially the same wherever form entered as a varia-
tion. If the color and size varied also, these were always sub-
ordinate means of recall. The form was the thing, and the
detailed analysis of errors given in the Appendix shows con-
clusively that to the subject it was the same thing whether it
was large or small, black or orange. Nevertheless, color and
size variations were by no means ignored. They entered as
secondary means of fixation, especially wherever a form was
similar to another in the same series or a past series. Here
the subjects differed some according to their own testimony
already given.
It is surprising that only one subject in the six, R., habitually
looked for resemblances to natural objects in the forms. There
had been no instruction on this point.
Compared to the methods employed in the series of pure
sizes and pure colors the form method was much more similar
to the color method, but less strenuous. Voluntary inter-term
discrimination was at a minimum because it was unnecessary.
The discrimination was involuntary, immediate (the subject
usually did not hunt for it) and sensorial rather than logical-
Here alone was contiguity grouping a leading and effective
method. The middle was frequently, though not always, fix-
ated and one or both wings might then form units consisting
for instance of a tall figure balanced by low ones on either side
of it, as in Forms B, and III. The subjects repeatedly said
that in form-varying series more than elsewhere they decided
doubtful cases by the appearance of the series asawhole. Not
that they had an image of the appearance of the series. Rather
certain arrangements tentatively made did not look right. In
thiiJ feeling they were more often right than wrong. ^Esthetic
considerations were prominent in series varying in form or
color, but discord was as effectf"- - —''■:':'■- "" i."™"."..
Digilizcd by Google
INFLUENCE OF COUPLEXITT AND DISSIUILAKITT ON MEUORT. 51
4.. Analysis of Errors.
For 3 detailed and probably more enlightening account
of all the errors made by two subjects, N. and R., pages 80-7
should be consulted. A general summary of the errors of
all the subjects will be sufficient here. Two types of errors
are distinguishable: confusion and simple fading out. By
confusion is meant all cases where the subject's arrange-
ment has wrongly followed an arrangement in some other
series or in another part of the present series, because of
some similarity in color, size, form, or what not. The confu-
sion need not be mental. Quite as often it is purely physio-
logical, as will be noticed below. We shall class all errors not
due to confusion as due to fading. An extreme case of fading
is the following: A young man who had recently spent five
years in the tropics was conscious that his mental processes
had become slu^sh, and his memory less impressionable.
On the second morning of work in our experiment, although
only one series of a kind had been learned the day before, and
only three in all, he said, when the duplicates of some of the
series were laid before him, that if he had been shown that
series the day before, he was not aware of it! Our classification
is the result, however, of the detailed analysis of errors. The
two types are not meant to be mutually exclusive, but only to
define predominant characteristics. It is true that confusion is
apt to occur only after a certain amount of fading has taken
place.
In the series of sizes, colors and colored sizes the type of error
which we have called confusion is overwhelmingly the prepon-
derant type. In the earlier series of colors the subject associates
certain colors with certain positions. In later color-varying
series he has to associate with the same positions colors which
in memory at least he does not distinguish from the earlier
ones. Interference arises, which is more often not noticeable
at the time of learning, if the learnings occur on different days,
but which becomes marked in recall after twenty-four hours,
and still more marked after two weeks. With the accumula-
tion of series in which the color varies, recollection in the final
Digilizcd by Google
51 HARVET ANDKXW PETERSON.
test becomes worse. The interference may or may not be
mental. It frequently Is so, but on the other Hand if the sub-
ject is following an arrangement in another similar group (sim-
ilar in almost any respect), he is apt to feel quite sure that he
is correct. After a number of color-varying series the subject
is apt to say when trying to recall their order in a final test
that the colors look about as well in one place as in another.
By this he means that colors which he has classed as yellow,
for example, have stood in a good many different positions,
and he is uncertain which one this yellowish term belongs in.
Exchange of colors in the same series is not as common as
confusion of different series, because in construction the colors
were intentionally varied; still, it does occur, for example
when two or more colors have been groupied on account of a
common property not reckoned with by the operator, as dull-
ness, brightness, complementariness, togetherness in the sub-
ject's past experience. We have had occasion before to speak
of intellectual classifications as a cause of confusion of position
when not followed by further discrimination.
In series of sizes and colored sizes confusion of terms within
the same series is much more frequent than in colors. This
means the sizes are less discriminable perceptually. Confusion
of one series with another may occur within the same half
hour (for example, pure sizes with colored sizes), and is more
marked with longer intervals. On the second and third day
of learning the subject may be aware of it and correct it panly
or wholly. Or he may be unconscious of it. The different
types of situations are the same as described above for colors.
It has frequently happened, however, that a size-varying series
has been arranged in a final test in the order of some other
series with entire correctness, and still the subject was not
aware of the mistake in identity! This has never happened
with colors or with form-varying series, and is an evidence of
the high degree of unity of the size-varying series, especially
pure sizes. In this respect they are the equal of form-vaiying
series. This is due to the 'sky-line' and mass-^roup systems
used in such series, and described above in connection with
the methods of learning. The absence of errors of the fatting
d by Google
INFU/ENCE OF COMPLEXITT AND DlSSIMlLdRJTr ON UEMORT. 53
out type in sizes is striking. Almost all of the errors made dur-
ing learning were exchanges of sizes nearest each other in area,
or nearest but one. Proof of this in the form of a quantitative
statement is given on pp. 61-62 in connection with some
experiments similar to these, and it is also shown very con-
clusively in less convenient form in the detailed analysis of
the errors of R. and N. in the present experiment, to be found
on pp. 80-7.
In series in which form-vartatton enters confusion is rela-
tively much less frequent than in colors^ sizes and colored sizes,
and fading out is more common, the total number of errors
being also much less. Exchange of adjacent terms, or inver-
sion, IS the most frequent error. It is due to not noticing the
individual terms closely enough (insufficient discrimination).
The subject relies on his sensory, non-logical impression, at
the point where the error later occurs. This is adequate for
the test which follows immediately after learning, but by the
next day many of these details have faded out. We agree
with Ranschburg that this type of error is relatively unimpor-
tant for studying the effects of similarity, because it is not a
stmibrity ^pe of error. However, confusion is by no means
absent from form-varying series. Confusion of terms within
the same series seldom occurs. Inspection of the plates shows
why. But the single re-using of an old form, or the occurrence
of forms which generically are the same, for instance two vases,
crosses, figures whose general contour is triangular, etc.,
produces interference and confusion, the more striking only
because it can be identified with more certainty, on account of
the individuality of forms. The poor average recall of Forms
II, Col. Forms III, and C. F. d. S. IV, and the individually
poor recalls of N. and R. in C. F. d. S. II are due to the re-using
of old forms.*
N. and R. took the' placet of F. and Mc.P. in the experiment and learned
the aeriea in a lomewhat different order from the one followed by the four
other (ubjeciB.
Digilizcd by Google
54 HARFET ANDBIW PBTEKSON.
§. Other Experiments with the Same Bases
Association with Temporal Order and with Numbers. In
the last set of experiments, limits to the benefit of increasing
the complexity in the direction of dissimilarity were found for
four subjects at the level of pure colors and pure forms. The
combination of color and size, themselves equal in difficult,
was no better than either alone; nor were the additions of
color and size variations, in themselves poorer than forms,
when added to forms, an aid. With two other subjects, how-
ever, the combinations were better than the variations singly.
With them the limits lie in some further increase in complexity.
We might have experimented with these two subjects further,
adding still more variations to the same bases, or using more
variable bases than colors and forms. Inviting as this was,
we preferred to test the generality of the conclusion that a
limit is to be expected with any subject on the level of pure
colors and pure forms. This we did by repeating the experi-
ments with new subjects, successive exposure and association
of the colors and forms with other associates than spatial
position.
The 24 series used in the foregoing section were given to
one new subject with successive instead of simultaneous expo-
sure, and he was required to associate each term with its tem-
poral position in the series. The cardboard screens, which
stood between the aperture through which the subject looked
and the carriage by which the series were moved, were nar-
rowed so as to expose only one term at a time. The series were
entirely remounted for successive exposure on cardboard sheets,
1 1 inches high and 42 inches or more long. Instead of having
all the terms rest on a base line, the middle points in the ver-
tical diameters of the terms were placed on a line running the
length of the sheet, midway between the lower and upper
margins. When a form arranged. in this way appeared top-
heavy, it was lowered until the unpleasant effect disappeared.
No fixation point was enforced. All of the conditions under
which the previous series were given as to avoiding names,
reviewing, use of duplicates to show the learner's progressive
Digilizcd by Google
INFLUENCE OF COUPLEXITT AND DISSIMIZJRITr ON MBUORr. 55
mastery of the series, the requirement that the series be held
perfecdy for 24 hours before the learning was discontinued,
were maintained here. The only changes were successive expo-
sure, final test after 6 days instead of 13 and arrangement of
the duplicates by the subject in their temporal instead of
spatial order. The interval before the final test was shortened
because successive exposure made the task more difficult. In
the various tests the subject, as before, did not see the dupli-
cates until the exposure was over. He then uncovered them
and arranged them in their time sequence, one on top of the
other, face down. Six series, one of each kind, were given
each week. The subject worked on four successive days each
week and a fifth if necessary to bring the series up to stand-
ard. Four new series were begun the first day and the remain-
ing two on the second day. The rate of exposure was 50
strokes of the metronome per minute with an exposure on
each alternate stroke. A term was thus exposed about 1.2
seconds. The subject regulated the number of repetitions of
the series which he took, but less than a repetition of the whole
series was never given. Thus the measure of the rapidity of
learning was the number of repetitions and arrangements
required to bring the series up to perfect retention after 24
hours. The following table gives the results. The figures on
the left and right sides of the dashes give the number of repe-
titions and arrangements respectively required to learn the
series; the figures under them give the amount recalled in the
final test, 14 being a perfect score. In the lower half of the
uble the same recall is recalculated per repetition of learning,
after reducing arrangements to their equivalents in number of
repetitions. This equivalent was found by special experiments
given for the purpose in the same manner as for the subjects
of the preceding group of experiments.'
'See pp. 65-7.
Digilizcd by Google
HJRFET ANDREir PETERSON.
trieJ in Color, Si'w anJ Form aiioci^rJ with Tiim
Pot il ion.
M;«<
U.
™....
.,™.
I.
n.
m.
IV.
I.
n.
m.
IV.
4-1
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3 5=
4-2
5 so
6-3
4.00
6-4
8.25
n-8
1 1. 25
7-i
5.50
6-3
6.50
,.„..
COLO»D tiat.
3-4
8.7S
4-4
3-1
11.50
3-2
10.00
6-t
5.00
*-*
5.00
6-4
6.50
+ .00
„„...„™.
c .■. d. t
11.50
3-4
14.00
2-a
6.50
.1^
14.00
3-2
11.50
' a-2
9.00
3-
700
*-3
8.75
cou,„.
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176
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.122
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.116
.061
■903
49'
1. 811
.589
.046
458
862
III
IV
.360
Av
■539
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COL. SRU.
COL. T
CUM.
c.d...
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M.V.
Rec.
M.V.
Rcc.
M.V.
1
304
.468
512
-443
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014
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I.44S
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1.103
970
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Av
454
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1 253
.366
1.392
■356
DiBiiizcdb, Google
INFLUENCE OF COMPLEXITY AND DlSSlMtLAKlTT ON MESiORT. 57
A Study of Table 6 shows that colors and sizes are remem-
bered about equally well and, as usual, forms better than
either. 7^e combinadon of color and size is not as effective
as either separately, but both colored forms and colored forms
of different sizes are more effective than forms alone.
Wth the subject U, and two new subjects, W. and X., the
same 24 series were next associated with the numbers 2 to 8.
The same seven numbers were used in every series. They
took the place of the seven spatial and seven temporal posi-
tions. Certain substitutions were also made in the series of
pure forms, the result of which was that no form was used
twice in all the form-varying series. This was effected by
substituting Forms A and B for Forms III and IV, and the
altemabve figures called B in the plates for those of the same
number, e. g., Fig. 6Bwas substituted for Fig. 6. Naturally
the order of presenting the terms was frequently changed to
prevent the entrance of position associations. The numbers
were of a large, fairly heavy style, 16 mm. high. Nos. 3, 4., 6
and 7 were black and 2, 5 and 8 were red, to reduce the labor
of learning, — an application of the advantage of variety to
our own experiment. The series in the form in which they
had been arranged for U- were used, and the numbers were
pasted on the centers of the terms. Where a term had been
lowered for xsthetic reasons the number was put on the hori-
zontal axis of the series, equally distant from the right and
left sides of the term. The altered orders used to prevent
position association were: ist rep., 1234567; 2nd rep., 2134567,
3d rep., 1235746, 4th rep. 1234576, then If more repetitions
were necessary, the same order over again. In the tests the
subject took a set of duplicate numbers mounted on circular
microscope slide covers and placed them on his duplicate set
of terms. All of the other conditions were the same as for
the subject U., as described above. With X. the interval
between the completion of learning and the final test was
reduced to 3 days, because a greater interval was too long to
produce sufficient recall. U. was used again in this experiment,
mainly because his time was at our disposal. This was a
divergence from the fundamental assumption of our problem,
Digilizcd by Google
j8 HARFET ANDREW PETERSON.
namely that the combination of variations must not already
have formed a unity in the subject's past experience. While
he had not associated numbers with the series, the combina-
tions of color, form and size were not wholly unfamiliar to
him. Nevertheless, his results present no important difference
from his previous work or from the results of the other subjects,
and they are consequently included.
The results of this experiment are given in Table 7. The
numbers on the left and right of the dashes give the number of
repetitions and arrangements respectively required to bring the
series up to standard, the numbers under them, the terms
correctly associated after three days for X. and six days for U.
and W. There were seven couplets in a series and a score
Table 7 — ^. Anas varied in Color, Sii/ and Form, astociatti vjtlh Numhert.
COLOM.
.™.
I.
n.
m.
IV.
I.
n.
ra.
IV.
6-3
7
10-6
8-4
5
5-3
3
■7-5
5-6
2
s-»
3
lO-II
5
3-2
4
4-2
22-11
3
6-6
5
5-5
9-7
9-7
5
7-3
i-s
3-2
7-4
5
lo-s
3
6^
5
9-7
5
7-6
5
X
FOMHa.
COLORtD tni*.
6-6
7
+-2
3
9-6
5
5-3
7
4-4
3
2-2
4
5-2
7
6-6
3
4-6
7
6^
7
6-4
4
4-3
9-6
3
S-4
5
9-4
7
14-1J
7
4-3
3
6-2
2
5-3
3-4
5
5-2
5
10-7
7
w..
,.„.„,.....
cr.d.i.
u
3-2
7
6-4
7
5-5
4
4-4
5
6-4
5
3-1
3
3-2
7
5-2
4
i-z
7
»-3
S
5-4
7
7-4
5
6-4
7
4-2
3
6-6
3
4-4
7
5-4
7
3-4
5
4-5
5
4-2
7
3^
7
6
4-2
7
3-'
3
DiBiiizcdb, Google
INFLUENCE OF COUPLEXITT AND DISSIUILASITT ON UEUORr. 59
Table 7.-
vied in Color, Site and Form, atiocialtJ viitb Number:
Recall per Repetition.
,OL„.
..„.
,.„..
c.u.„...
„u,.«,.
c.
d...
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IV.
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.156
.237
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.006
.079
43*
3
!26l
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.332
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1. 103
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1. 103
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• Mtmtmd ar^ af nunAtri ailj.
Summary of Part B.
COLOU.
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1.050
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-'33
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.105
*'■■•■
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L
Di,i.izodlyGOOgle
60 HARVEr ANDREW PETERSON
of 1 was allowed for each correct association, with no partial
credits. Part B of the same table gives the same recall per
repetition, after calculating in the equivalents of the arrange-
ments in terms of learning time according to the method
described on pp. 65-7. A numerical summary follows the
table and a verbal summary is given last.
Summary. Two of the subjects do considerably better with
colors than with sizes, while the third, X., does not recall
enough of either for comparison. For, as indicated in a foot-
note to Table 7, part B, he learned only the numbers in Sizes
III and IV. During learning he mentally arranged the num-
bers in the order which they would have if the sizes had been
exposed in the order from smallest to largest. These two
series should therefore perhaps not be counted, /til three
subjects Jo markedly better ivith forms than with sizes and
colors, ffith U. and W. colored sizes are not better than color
alone, but size is substantially improved by the addition of
color as would be expected. But with X. colored sizes are
much better than either color or size alone. This is confirmed
unqualifiedly by the introspections of the subject. For him
pure colors or sizes were almost impossible after the first series
of each, partly on account of their inherent difficulty, but
more because of the interference of past associations. He
made in memory few if any more color discriminations than
the seven of the spectrum, ^ilh U. colored forms and colored
forms of different sixes are both more effective by considerable
amounts than forms alone, — an outcome which duplicated his
records in the associations with temporal order. The subject
X. also profits by the increased complexity in both cases, — colored
forms and colored forms of different sizes. His recall is prac-
tically doubled in both cases, compared with pure forms.
Here again the introspections confirmed the results, ff. on
the contrary is not benefited by the additions to form. Colored
forms are even poorer. It is interesting to note that the three
subjects differed very widely in natural retentiveness, that the
one who remembered the least profited the most from increased
variety, while the one who remembered the most did not profit
by the additions in any case. U. occupies a middle place in
.yGoOtjIr
INFLUENCE OF COUPLEXITT AND DISSIUILARITT ON MEMOBT. 6l
respect both to natural retentiveness and die use made of the
addidonal variations. When asked at the close of the inves-
dgadon whether the presence of color and color-size variations
in the form-varying series was a help, as constrasted with pure
forms, W. replied, "Only occasionally, when the forms are
similar. As a rule I find sufficient variety in the form alone."
And yet she did not take the forms to be copies of objects,
except in the most obvious cases. They were simply colored
areas. On the other hand X. looked for resemblances to
objects constandy, and found them usually.
The distribudon of the benefit of increased variety is the
same as we have found before. The learning dme is shortened
and snil the amount recalled after a week isgreater. U. learns
forms in an average of 5.25 reps, and 5 arrs., colored forms
in 3 reps, and 2.75 arrs., and colored forms of different sizes
in 4 reps, and 3.75 arrs. His average recalls are 5.75. 6 and
6.25 terms respecdvely. X. learns colors in an average of
14.75 I'^ps- ^nd 8.25 arrs., sizes in 8.50 and 5.75, colored sizes
in 9.50 and 6.50. His average recalls are 2.25, 2.50 and 4.50,
respectively. He learns forms in 5.75 reps, and 5.75 arrs.,
colored forms in 4.50 reps, and 3.50 arrs., colored forms of
different sizes in 3.75 reps, and 4 arrs. His average recalls
are 4, 4.75 and 4.50.
The results with these three subjects simply confirm and
extend the conclusion reached with the six subjects. The
change to successive exposure and a different association has
shown no change in the conditions of learning nor in the results.
After a brief treatment of two somewhat different topics in
the next three sections, the results of the whole investigation
will be brought together in the Conclusion.
6. Analysis of Errors.
In the 24 simultaneous series begun in V 2, it was found
that in colors, sizes and colored sizes, confusion was quite
decidedly the most frequent cause of error, and the detailed
analysis of R.'s and N.'s errors would have shown that both
of the possible kinds of interference, namely of terms within
Digilizcd by Google
62 HARFEr ANDREW PETERSON.
the same series, and of ditFerent series with each other, were
equally prominent. In the present experiments successive ex-
posure made single schemes for the whole of a series prac-
tically impossible and the influence of past series became less.
Memorizing became much more a couplet affair. The inter-
ference in the series of sizes and colored sizes particularly was
almost wholly traceable to terms in the same series, as shown
in the following summary, in which is included every error
made in all the series in which there were three errors or less.
It includes U.'s temporal-order series and U.'s and X.'s num-
ber association series.
Sit,.
ind Colored Stxet
•IIB]ICT
— "— "■
«»■.
HUIUT
•lUtlUT
ALL
TOTAL.
8
21
'7
*
♦
5
O
4
'1.
u
Total
+6
'3
6
H
By nearest sizes is meant sizes nearest each other in area.
These sizes were simply mistaken for each other. In the new
summary the proof is less certain only because color similarity
cannot be so objectively defined. Its definition is due to the
opinion of the experimenter, aided by a Bradley Color Book.
We included in our definition only colors obviously similar in
perception, and therefore quite certainly took a narrower defi-
nition than the limits within which colors would seem similar
in memory.
U....
U....,
Temporal Order
Number Associations . ,
Numb«r Associations , ,
DighzoclljyGoOC^Ie
INFLUEttCE OF COMPLEXITT AND DISSIUILAMITT ON ItEMOKT. 63
In the form-varying series of the temporal order set of U.,
inversion of adjacent terms was the most common error, vrhich
result agrees with those of the corresponding spatial position
associations. Of the 22 errors made in all the series in which
3 errors or less occurred, 15 were exchanges of adjacents, 4
were due to similarity in form and 3 to no assignable cause.
Of the form-varying series of the number associations the only
statement that can be made is that confusion due to similarity
was less frequent than in the series of sizes and colors. Inver-
sion of adjacents is here not a possible type of error on account
of changes of the order in learning.
Tl. INDIVIDUAL DIFFERENCES IN SPEED OF MEMORIZING AND
IN RETENTIVENESS
If the differences in material be disregarded, the experiments
described in V 2 give results from six subjects with the same
24 series. Since all of them were required to learn the series
in the same way we may compare the subjects simply as learners.
The three subjects used in die experiments with numbers can-
not be compared with the first six only among themselves.
The following table is compiled from the averages for the
different persons given in Tables 4 and 7. Part A below
gives on the left the average number of seconds which each
of the first six subjects required to bring the series up to the
point where he had held its arrangement perfectly for a day.
On the right side are given the average amounts recalled,
marked on a scale of 14. In part B similar averages are cal-
culated for the three subjects in the experiment with numbers.
These figures also are based on 24 series and the amount
recalled is based on a scale of 7. The subjects are arranged in
order of speed of learning and amounts recalled.
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HJKFEr ANDREW PETEXSON.
Tablb 8.
Part A.
lUBJICTt.
,„.
A»l. •DBJlCn.
.tS^i.
S.38
♦■71
7.88
308
4 17
5. 63
5.04
3 7i
X
X
N. learns rapidly and retains well; R. learns rapidly and
retains moderately. H. is just the converse: he learns moder-
ately, being a tie for third place, and retains well. G. learns
moderately but does not retain as well. J. gets some recom-
pense for his extra effort, while L. learns slowly and retains
with difficulty.
W. and U. learn rapidly and retain well, there being very
little difference between them. W. is the more retentive for
longer intervals. For a week — the interval of their test —
there is no difference between them, but W. retained series for
weeks after U. had forgotten them. X. learns slowly and has
difficulty in retaining.
Temperamental differences also come out in the willingness
to take a chance. This is shown by the number of arrange-
ments. N. and G.were speculative. They frequently termi-
nated the exposure of the series before they had learned them
sufficiently. These were the subjects who had on occasion to
take five days to learn the series instead of the usual three.
L. and J. are cautious. When they end the exposure it is safe
to say they have the series for that day, and quite probable
that they will have it the next day without re-exposure.
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INFLUENCE OF COUPLEXlTr AND DISSIUlLARJTr ON UEMORT. 65
VII. EXPERIMENTS TO DETERMINE THE VALUE OF ARRANGING*
After all of the foregoing experiments had been completed,
12 series were given to the subjects, G., H., J., L., N. and R.
There were four series each of colors, sizes and forms. Two
of each were learned in three successive days all six being begun
on the same day. The other six were given the next week.
In one of the two color series of the first week arranging was
required as in all the foregoing experiments, in the other it
was omitted till the final test. The same is true of the two
series of sizes, and the two forms learned the first week. The
times of exposure were the same for every correlative pair,
the one with and the one without arranging. During the
first week the series with arranging preceded their mates to
allow the subject to determine the length of the learning periods.
However, to prevent the series without arranging from being
at a disadvantage from too short exposure, certain extra expo-
sures were given by the operator on the third day. To be
' This question is very imponant wherever it is desired to study the learning
process as wdl as the recall. For in order to ascertain the learner's progress
towards complete temporary mastery of the material it is necessary to test him
froni time to time. This gives two differetit measures, learning time and testing
time or number of tests. The attempt to reproduce a material nearly always
aids in memorizing it. Ebbinghaus assumed that a test or attempt to repeat
a series is equivalent to a presentation of it, but this is clearly unsatisfactory.
Stephan Witasek has made an exhaustive study of the relative efficiency of read-
ings and attempts at recital in biingingseries of nonsense syllables up to perfect
metnorization, and in producing recall after an hour. (Ueber Lcsen und
Rezitieren in ihren Beziehungen zum Gedachtnis. Ztsch. f. Psych., 44: 161-85
andZ46-82.) He found that for immediate recall 6 readings and 5 recita-
tions enabled the persons to recite the series in one half the rime required by
II reading! alone, and required only one thirteenth as many promptings.
{The Ebbinghaus prompting method is the one referred to.) The superiority
of the recitation in producing recall after an hour is not as marked as in immed-
iate recall. Thus various mixtures of readings and recitations, the readings of
course always preceding, compared with an equal number of readings alone,
dfected an average saving of about II per cent in time and 16 per cent in
promptings in the final test. The forcing diarr^rds time consumed by the
two methods. A recitation aided by promptings takes more time than a reading.
However,the author shows that even on a time basis a combination of readings
and recitations is more economical than readings alone. From any point of
view recitations are far superior to readings in impressing value. The signifi-
cance of this resultfor pedagogy.for determining the best methods of study, is
worth noting.
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66 HAnrsr andrmw petekson.
more explicit, on the Hrst day the subject wholly determined
the time. He took as much as he thought would enable him
to arrange the first series of each pair correctly the next day,
and the operauir allowed him the same time on the second
series of each pair. On the second day the procedure was the
same // he did not have them correctly in the preliminary test
of that day. If he tHJ have them correctly, he was given a
7-second exposure of both series of the pair. The procedure
was repeated on the third and last day, for sizes and colors,
but forms were dropped after the second day, because they
would have been over-leamed by continuance. The aim of
these condidons was to bring the series approximately up to
our previous standard, perfect retention for a day. However,
since having arranged a series was equivalent to seeing it
again, and since it was desirable for exactness to spread the
learning time of both types of series over the same number
of days, it was necessary K) give a brief exposure of both series
(the one with and the one without arranging) whenever one
was seen. This was the purpose of the 7-second exposures.
Hence our procedure was slightly different from the one used
in the past. In the second week the operator wholly deter-
mined the length of the learning times, and made them the
same as the series of the first week for that subject. The
series without arranging now preceded its mate. Finally,
there was a reversal within the pairs. The series in connection
with which three of the subjects arranged were the ones with
which the other three subjects did not arrange. The purpose
of this reversal was to test the assumed equality in difficulty
of the correlative series. The results substantiated the assump-
tion in the main.
All the other conditions were the same as in the simultaneous
series of V 2. The subject was required u> associate the terms
with their spatial positions. The series were displayed on
cardboard sheets, 14x22 inches, the arrangement being in
three vertical columns of two terms each, except the middle
column, which had three. The usual expedients to minimize
interference, in particular, individual senes-shape and series-
color. Were used. The final test of the first six series occurred
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INFIXJENCE or COUPLEXtTr AND DlSSIUILdKITr ON MEUORT. 67
in the midst of learning the second six in order to retain the
normal interference factor, constantly operative in our past
work.
The procedure with the three successive subjects U., W. and
X. was similar. The consonants G, H, N, P, Q, W and Y
were associated with 12 series, 4 each of colors, sizes and forms.
Three of the letters were white, the rest black. The learning
conditions were modeled after those described above, while
the testing conditions were the same as in the regular work of
these subjects.
. For the six simultaneous subjects the value of an arrange-
ment was determined by dividing the total number of seconds
spent in learning the six series in which there was no arranging
by the number of terms recalled in those series after a week,
and then dividing the difference between the total recall in
the six series with arranging and the six without, by the total
number of arrangements used. The first operation gave the
number of seconds of learning time that would produce one
term in recall with this subject, while the second operation
gave the number of arrangements, or the fraction of an arrange-
ment, that would produce one term in recall. These two
quantities were therefore equivalent. Precisely the same
method was pursued in calculating the value of an arrange-
ment for the successive subjects, except that the learning times
were given in repetitions instead of minutes and seconds. The
values thus obtained for the different subjects were as follows:
Vdut of an
Arraifgemenl.
•OIJICT.
.»;<o.
1 .».,>cr.
5MC..
12-35 sees.
21.8 sees
L
N.
R
10 sees.
12.35 sees.
U
W
X
1.673 reps,
neehing
2.617 leps.
J
For the two subjects who were dropped from the experiment
after the series of grays and violets, McP. and F., 10 sees, was
taken as the value.
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HARFET JNDREIf '
In summing up the results of t
call attention to the fact that it i
into the effects of novelty on memi
the same typographical variations
for eight consecutive weeks, nor tl
areas for over four months. The
the effects of simplicity with dis
few types of each are used a long
Language, spoken and written,
simple and similar. The sameness
with the variety afforded to the eye
is striking. The possibilities, h
memory for language, by introdu
as suggested to us by the experii
proved to be decidedly limited. I
meaning, as is the case with non
the memory is permanently impro'
variations, particularly position a
of variations be increased conside
distraction enters, there is no furt
may be a loss. That such variatio
ing the attention, when they have
popular conviction which experim
If, however, the variation takes thi
of one thing than of another, the
tainly better than the memory for
experiments of Prof. Calkins.
But language differs from nonser
ing, in itself a powerful variation, :
give no basis for the belief that i
permanently better, when the won
Our ov?Ti experiments were few i
When the attempt is made to vary
technique arises, which is by no i
the difficulty of keeping the simpl
connected. Even single adjectives
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INFLUENCE OF COMPLEXITT AND DISSIMILdRlTr ON MEUORT. 69
gest acquired connotations so readily that the material rapidly
becomes complex, and has the advantage over the material
called complex that it is already made up of units. This was
the case with our experiments with words and sentences, and
numbers and biographical facts. However, the results at least
show that when the learning time is fixed and sufficient for
comprehending the meaning of both, short sentences can be as
well remembered as single words. All three of our language
experiments showed conclusively that a person will seek differ-
entials among the things to be associated, but will give the
preference to ones already connected in his experience, if they
can be found.
We pass next to the experiments with plane areas. We
found that forms were far more associable than colors and
sizes, that is to say, the associations were much more quickly
established between forms and something else than between
colors or sizes and something ebe. In this result all nine sub-
jects agree. We know of no other experiments on this subject
except those of Bigham.* He found that colors were slightly
more associable than forms in immediate recall, but after 2
hours and 24 hours the result was the reverse by larger diflFer-
ences than before. The res'onse times in immediate recall
of forms were also longer than in the case of colors. His
method was similar to ours in the use of duplicate series for
testing, but differed in the very important respect that the
same ten forms and ten colors were used over again in every
series. The test was association with position as in our experi-
ment. The re-use of the same forms would under these
circumstances produce interference, the greater for forms
because of their more ready associability. The better recall
of forms after two and after twenty-four hours, that is the
fact of reversal, cannot be understood without knowing how
many series of a kind were given.
The relative associability of sizes and colors differs in our
results with different subjects, with the balance in favor of
colors. Four persons remember colors better; two, sizes; and
' Bighain, Joha: Memoiy. Piych. Rev., 1894, 1, 453.
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HAKTEY ANDRSr PETSKSOff.
two show no marked difference. The ninth subject is dis-
regarded because of low recall. However, if the slighter differ-
ences shown by two persons classed as equal be counted, six
remember colors better than sizes, while two are the opposite,
and by very large amounts in both cases.
The very great superiority of forms over colors and sizes ts
certainly due to the far greater variety within a limited space
which the realm of forms off'ers. Had all the form-varying
series, instead of one-half, consisted solely of forms used only
once, the superiority of forms would have been still greater by
a considerable amount. Yet as many forms as that could
easily have been found without making the similarity great. The
simple fact is that there is a large number of easily discrim-
inable forms, while there are only a very few easily discriminable
colors and sizes, so far as the memory for long intervals is
concerned. On the other hand the experiment does not do
justice to the possibility of color. It would be interesting to
know what would be the result of combining several colors in
each term. Tlie striking color effiects of practical life are
oftener color contrasts than single colors. While only experi-
mentation can decide the question, our own results lead us to
expect only slight improvements for color from this source.
While our earlier experiments were relevant to the memoiy
for language, the later ones with plane areas are like the mem-
ory for objects, and here our results were much more positive
and extended. We may disregard the diff'erences between the
associations with position and those with numbers, and treat
all nine subjects together. The questions raised in the original
statement of our problem may be answered as follows. On
the low level of variety represented by shades of gray and shades
and tints of one color, the advantage of additional variations
is great and is manifested by all six subjects tried. By a men-
tal economy the additions, here more easily discriminated than
the grays and violets, become the more prominent, although a
bona fde association is made between them by the time the
learning process is complete. In most cases the person could
tell which gray, or shade or tint of violet, went with a form or
size, if given both variadons to put together. This process of
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INFUJBNCB OF COMPLEXITT AND DISSIUILAUTT ON IHEMORT. 71
remembering a less discnminable thing by a more discrimtnable
associate is easily identified in life. Students distinguish their
notebooks by the fasteners, marks of rough usage or even
bits of color. Books are distinguished by their variation in
color> because the shape is so much less discrimtnable. In
education arithmetical rules are clothed in striking examples.
With the passage to the higher levels represented by different
colors and different forms, when the variations added are less
discnminable than the bases, five of the nine subjects no longer
profit by the increase in complexity. The two other persons
in the simultaneous position associations and two in the num-
ber associations with areas still profit. No limit was found for
them. When, however, the variation added is more discrimin-
able than the base,allofthe subjects again profit by theaddition.
This is the case when in our type of series called Colored
Forms a form variation is added to color. The advantage is
almost as marked as on the lower level.
The question why the increases in complexity cease to be an
advantage is next in order. The ability to profit by these
increases is not a function of speed of learning, as would
naturally be expected. Quickness in learning here represents
good powers of discrimination and facile associative processes.
The figures given in Table 8 show that of the four persons who
profited longest by the increases in complexity, R. and J., and
U.andX.,two rank first and two last in rapidity of learning the
series. The ranking is the same if only pure colors, sizes and
forms are averaged. This restriction can be demanded with
some justice, because if those who have trouble in discriminat-
ing the terms are the ones who profit longest by the added
variations, their slower discrimination would show itself most
before the variations were added.
On the other hand the five to whom the complex material
was not the better are in agreement as to the presence of dis-
traction in the complex series. While distraction is therefore the
most probable cause at the present time, special experiments
on the span of attention are necessary to decide the matter.
It is now possible to offer an explanation for some of the
differences in the memory for different materials, and the same
ly Google
72 HARFET ANDREK' PETERSON.
materials learned in different ways, which were spoken of in
the beginning. Objects, actions and pictures are better remem-
bered than words, because they are more extensive and varied
stimulations. Both get a certain amount of variation from the
ideational suggestions called forth, by the connotations, in other
words. It is probable that the ideational supplementation is
somewhat richer for words than for objects, actions and pictures.
But with most persons imagery is feeble compared with sen-
sory stimulations, and we are inclined to believe that the advan-
tage which words may enjoy in this respect is relatively slight.
On the other hand in the extensiveness and dissimilarity of
sensory stimulations a series of words cannot compare with
a series of objects or pictures. This is ludicrously brought out
when one attempts to handle type. We rest our eyes from
print by looking at our surroundings. Contrast the extent and
variety of stimulation obtained from looking at a house, a
lawn, a lamp, a knife, a piano-player and a moving train of
cars with the smallness and similarity of the stimulations
obtained by looking at their printed words just given, or even
printed and read aloud. Corresponding to the more exten-
sive and varied original brain excitations of things arc the more
easily aroused and numerous mental cues in recall, and the
greater likelihood of freedom from the interference due to sim-
ilarity. If the brain excitations obtained from seeing and hear-
ing the series of things mentioned above be denoted by the
letters ABCD, DEFG, GHIJ, etc., those obtained from looking
at their printed names and speaking them should be represented
by the letters mnop, nopq, opqr, etc., even after the differences
due to suggested imagery are included.
The explanation is the same for the fact that words presented
to several senses are better remembered than those presented to
one only. Whitehead has shown that when things are learned
visually, there is a filtration, so to speak, through from our visual
to our auditory experience taking place at the time of the visual
learning, so that if a week later the same thing be learned audi-
torily, it takes but little more time than to relearn it visually, and
of course much less time than to learn a new series auditorily.'
' Whitehead, L. G.; Psych. Rev., 1896, III, p. 258.
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INFLUENCE OF COUPLEXiTY AND DISSIUILARITT ON lUEUORr. 73
The same thing is true if the first learning is auditory and the
second visual. Here as in our own experiments the connecting
process goes on during learning, but in this case the connec-
tion is with images instead of other perceptions. The same
process takes place in learning through several sense organs at
once. If we not only see but pronounce, we get a more varied
stimulation than if we merely see the words, and if we read
them aloud the stimulations are still more varied compared
with the visual alone, and the liability to confusion in recall
is correspondingly less, just on account of this growing varia-
tion. Doubtless the well-known summation effects of a number
of weak stimuli are also responsible for the difference. We
seem to get the meaning more completely when we read a page
aloud than when we read it to ourselves. This indicates that
the visual, auditory and enunciatory stimulations combined
are more effective than one or two alone in arousing associa-
tions of an ideational type. Funhermore, it is not to be for-
gotten that we are dealing here, in the case of language at least,
with complexes that are already apperceptive units, owing to
early schooling. The case is somewhat different from that
of our own experiment, where the combinations were con-
stantly new.
One of the original and less common features of this inves-
tigation is the length of the interval before the memory is
tested. There are few extended investigations of the memory
for materials after intervals as long as one and two weeks.
Finally, to the technique of memor)' work we offer a contri-
bution. T^e method of measuring the memory for different
materials by the amount of time or repetitions required to
bring them up to the same level of efficiency meets with the
difficulty of evaluating the tests taken to determine progressive
efficiency. We propose a solution of this difficulty, namely, a
separate determination for each person, of the average worth
of a test in terms of learning time or repetitions, the two meas-
urements to be rendered equivalent through what each will
produce in recall.
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74 HARFBT ANDREW PBTESSON.
IX APPENDIX.
I. Pliaet.
The following plates give the shapes and rtlativ* sizes of the fomt-vaiying
series. The anual dimensions and the colon employed arc |^ven in the
'Description of Series' on the pages immediately succeeding.
With three subjects U, W, and X, certain (bnns, here called 'Substituted
FontiE,' replaced some of those in the regular series in order to eliminate repe-
tiuon. They are numbered to correspond with the figures which they replaced,
and the distinctive letter B is added. The first three forms, iB, 4B, and 5 B
belong to Forms I; the fourth, 7B, belongs to Forms 11; and the last two in
the row, iB and 6B, belong to Forms B. In the nest row iB, 3B, and 7B
belong to C. F. d. S. Ill, and the remaining five belong to C. F. d. S. IV.
2. Detrriftion of Stria uied in V 2 anJ 5.
Colors. Each term eontaintd jo tj. cm.
Series I. Ei^-point stars. Yellow orange t. 2, green, cool gray no. 1
blue sh. 2, A-yellow medium, green yellow t. 2, red orange sh. i.
Series II. Squares. Orange red t. 2, yellow orange sh. 2, A-blue green dark,
yellow, red, green t. 1, A-rcd light.
Series III. Oblongs. Orange yellow t. t, red violet sh. 2, orange red 1. 1,
blue green sh. i green yellow t. 1, A-green yellow dark, A-green light.
Series IV. Round-cornered squares. Black, violet red t. 2, orange red ah.
2, cool gray no. 2, green sh. 2, A-yellow orange medium, green blue sh. i.
Sites. Series I. Red oblongs, hei^ rwice the width. Irregular ratio of
terms as follows: 1 :2 -+,2 :3 =306, 3 14 - 1.24,4 =5 - '5. 5 =6 -1.4,
6 7 - i-S-
Series II. Equilateral' triangles. A-yellow orange dark. Geom. ratio,z.77,
beginning with an area of .5 sq. cm. for the smallest.
Series III. Circles. Blue violet sh. 2. Geom. ratio, 2.77. Smallest term.
Series IV. Truncated cones, sides inclined one-tenth the width of the base
on each side. Yellow orange, and irregular rario of terms as fellows: 1:2 —
3-9. »; 3 " 4'. 3 ; + - *-98, 4:5- 1-69. 5:6- a>> 6:7- t.9.
The order in which the sizes were placed in any series was determined by
chance as in the gray and violet sets, excluding the cases there excluded.
The arrangements employed in the above series were the following, reading the
series from left to rig^t. The figures give the areas in sq. cm.
Series I. 40.5 60.5 2 8 84.5 128 24.5.
Series II. (1 is the smallest) 1625347-
Series III. 2451376.
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INFLUENCE OF COMPLEXITY AND DlSSlMlLAKtTr ON UEMORT. 75
□
u
VIOLET FORMS
FORMS
A
2/^ ^^ r~\'
u
m
crr^Vop'dU'O'
DiBiiizcdb, Google
BAMFET ANDROr PBTEX30N.
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INrUJEXCE OF COMFLEIITT AND DISaiKILAKITr ON MSKOET. JJ
COLORED FORMS OF DIFFERENT SIZES.
I
SUBSTITUTED FORMS ^ f
^
JB \ /SB
DiBiiizcdb, Google
BARFET ANDREW PETERSON.
Sciict IV. 1.95 .50 40.6 162.2 24 8.05 84.
It will be noted that the aggregate area of each series n
B 350 iq. cm.
Colored Saes. These series are the simplest advance in complexity. A* the
name indicates they vary in area and color. To render them comparable with
series varying in size only, the term-areas of Series I repeat those of Sizes I,
Series 11, of Sizes IV, Series 111 and IV, of Sizes II and III. The series-chapes
were however new. The order of occurrence of the terms may be represented
as follows, the topmost one being on the left end. The figures again indicate
the sizes, i representing the smallest, 2 the next smallest, etc. The combination
of color with size was determined by chance after the seven colors for the series
had once been selected. However very small terms were not given very li^t
2 yellow green
3 yellow orange darlc
7 orange yellow t. 1
6 red orange
4 blue green sh. 2
5 violet t. I.
S/i-r« ///.
3 A-^ecn medium
4 Uue t. I
7 A-orange red dark
5 green yellow t. 2
- I black
6 A-orange light
2 A-red violet dark
Formi. (See plates.)
Stritt II.
2 blue
I orange red
5 orange sh. I
7 yeil«
4 green yellow
3 blue t. 2
6 red violet t.
ingei.
Series IK
3 violet
6
3 violet
1 A-green yellow dark
6 blue green sh. i
2 A-yeltow orange light
5 green blue t. 2
4 red orange sh. 2
7 yellow t. 2
Colored Forms. These series also varied in two ways, color and fonn. The
forms are given tn the plates. Each term contained 50 sq. cm. The colore
in order from left to right in the series were as follows:
Series I. Fig. I yellow, Fig. 2 A'^reen medium. Fig. 3 red violet t. i, Fig.
4 yellow green. Fig. 5 black, Fig. 6 A-orange red medium, Fig. 7 orange t. 2-
Series II. Fig. I green, Fig. 2 orange. Fig. 3 orange yellow sh. i, Fig. 4
red. Fig. 5 green I. 2, Fig. 6 yellow orange sh. z. Fig. 7 violet.
Series III. Fig. I A-yellow orange dark. Fig. 2 blue sh. 2, Fig. 3 red t. I,
Fig. 4yellow green. Fig. s orange yellow t. I, Fig. 6 red violet sh. I, Fig. 7 yel-
low green sh. 2.
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INFLUENCE OF CQMPLEXITr AND DISSIMILABITT ON UEUORT. ^q
Seriei IV, Fig. i warm gray no. i. Fig. i orange yellow t. i. Fig. 3 green
yellow t. I, Fig. 4 blue t. I, Fig. 5 A-orange red. Fig. 6 violet red. Fig, 7 A-yel-
low orange medium.
ColoreJ Formt of Different Siiei. These series varied in three ways and
reprecented the maximum number of variations which were combined in a single
series. The variations were in color, size and form. The forms are given in
the plates, the sizes and colors, here. The ratios existing between each two
incccsnve terms in series 1 and II were the same as in Sizes I, and the actual
areas were also the same as there. In series III and IV the ratios were
I : J -4,2:3-2.25.3 :4 -2,4^5 -2.17.5-6 - 2.6,6:7 -3.25.
I :i- 2.5,2:3 -2.5,3:4 = 2,4:5-2.5,5:6-2.17,6:7-1.35.
Fig. I 8. sq, cm A-yellow orange dark
■ 2 84.5 " violet red
' 3 40, 5 " A-yellow light
" 4 128. " yellow
- 5 2. • A-bluedark
■ 6 24.5 " yellow green sh. 2
" 7 60.5 " blue
Fig. I 60.5 sq. cm gt^en t, i
■ 2 24.5 ° orange yellow sh. I
' 3 '28. " warm gray no. 2
■ 4 I. ■ orange red
" 5 84.5 ■ green blue sh. I
" 6 405 ' orange
■ 7 8. ' A-red light
Seriet III.
Fig. I 19.2 sq. cm black
" 2 162, " violet
" 3 4-5 " orange yellow sh. I
" 4 9. ' red violet 1. 1
' S 50- * yellow green sh. 2
Series If.
Fig. 1 43 . 75 sq. cm blue violet
■ 2 128. " green blue sh. I
■ 3 17.5 " violet red
' + 3-5 " wann g"y "»■ 2
" S 8.75 " green yellow sh. 2
" 6 I.+ * red sh. 2
" 7 95. " A-yellow light
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8o SARFET ANDMBF PETSHSON.
Each of the firtt two Mries aggregate! 348 sq. cm., the third 347 and the
founh 298 sq. cm.
Extra Serits. Colors A. Blue sh. 2, yellow orange sh. 2, violet, orange,
green, A-violet blue light, red. Oblongs, height twice the width.
Colors B. A-yellow light, red violet t. z, red t. t, jvllow, warm gray no. z,
blue green, yellow green t. I. Same series-shape as in the preceding one.
Sizes A. Isosceles triangles, height twice the base. Blue t. 2, gcom. ratio
of 2.5 beginning with an area of .5 sq. cm. for the smallest term. Total area
of series, io+ sq. cm. Order: 5416372.
Sizes B. Truncated Cones, A-yellow dark in color. The ratios were I : 2 ~
4.5, 2:3- 2.78, 3:4- 1.6, 4:5- 2.03, 5:6- 1.3, 6:7- 1.92. The
actual areas in order from left to right were, in sq. cm.: 25 64 2 169 9
324 130. The total area was 723 sq. cm.
Sizes C. Quadrilaterals fbmied by superposing upon a square a right
triangle of the same dimensions with hypotenuse to the left. Green sh. z in
color. The ratios were, 4, 4, 3, 3-5, I.93, 1.5S. The actual areas in their
orderwereinsq cm.: 2 t6l 24 84 256 .5 8. The total area was 536.5
CiJortJ Sixes A. CoiortJ Shti B.
4 blue green 5 orange red sh. t
2 red orange t. 2 2 green sh. 2
7 warm gray no. i 4 orange yellow t. i
5 green t. 2 3 red t. 2
I red orange 7 cool gray no. 1
3 blue t. [ I A-yellow orange dark
6 A-green yellow medium 6 blue
Forms A and B. These are sufficiently described in the plates. The results
obtained from them were not used in the tables, because the forms in them
had been used once before, and there was already a sufficiency of such series.
}. Analytii of Errort in V z.
In the pages immediately following the errors of Tables 4 and 5 will be
analyzed. The results of two subjects will be treated in detail including every
series, eveiy error in the final test and some of the errors made in learning.
Some of the explanations are conjectural, and of questionable worth; many
otheis are beyond question the true causes of the errors. The account is to
a very laige extent a story of interference due to similarity. It will be recalled
that introspccrions were not allowed Iwfore the final test, so that when th^
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INFLUENCE OF COMPLEXITr AND DISSIMILARITT ON MEMORT. 8l
were given, moat of them were not of value. The conclusioni given below aie
therefore mainly the result of a study of the arrangements of duplicate series
handed in bythe subject. Where introspectiont were used it is made evideni in
the text. The extra series denoted by the letters A, B, etc., are included. It
is essential to remember that in the interval of 13 days between the learning
and the testing of a series two more rotmds of similar series were learned.
When the particular test is not mentioned it is alwajn the fnal one that is
meant. By 'wing' is meant the three terms on either side of the middle term.'
Sahjict R.
Col. Sizes I and II, and Cols. A. In learning Col. Sizes I the only error
was an exchange of 3 yellow orange and 4 blue green belonging in 2d
and 6th places respectively. The error was probably due to their similarity
in size. It occurred three times on successive days. When the next week Col.
Sizes II was learned the influence of I was shown'in erroneously moving green
yillow from 5th to 1st place where a yellow grten had stood the previous week.
The error occurred twice, with no others. When in the third week Col. Sizes
I received its final ten, aside from an exchange of two small adjacems, 3 yellow
otangeandi red, theonly error was a removal of yellow ^mk to 5th place. Here
the corrections which the subject got in II worked to the undoing of I. When
the following week II is tested the only error is moving green yellow to the left
end, this time to second place instead of to first. The original error has recurred.
Cols. A, which was learned with Col. Sizes I, shows the influence of this strug-
^e. Its yellow orange is moved from id to 7th place, its green from 5th to
3d place. This is very much like the first-mentioned error in Col. Sizes I.
The only other errors were an exchange of adjacent!, violet blue and red.
C. F. d. S. III. Exchange of adjacent terms in final test, one pair only.
Forms I. In the final test aside from one exchange of ad jacents, the errors
are caused by moving Fig. 7 to 3d place. No explanation ascertainable.
Sizes B and C The kind of schemes or systems most frequently made use
of by all the subjects when the exposure was simultaneous is well illustrated
by the one us^ by R in Sizes B. The correct order was 3416275, I repre-
senting the smallest, 2 the next smallest tetm, etc. Her system according to
her own testimony was an ascending 'sky-line' from 1st to 6th places, 3467,
the smallest and next smallest forming a second ascending series interpolated
in the first at the 3d and 5th positions. The last term stood apan. In the
final test the general nature of the scheme remains, but the details have become
'To understand these analyses of errors the Description of Series on pp.
74~8o doubtless will have to be frequently consulted. The prefixed figures 2,
3, etc., m^n the second size, third size, etc, counting from the smallest.
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8a HJRFEr ANDREW PETERSON.
confused, as shown by her arrangement 3451726, The next week, when Size*
C came up for final test the system which the subject had employed in learning
B was introduced into C with entire correctnets. The subject is of course
unaware that it had belonged to another series. This is only one of the many
striking illusttations in our experiment of the law discovered by Miiller and
Pilzecker, that of two similar and mutually interfering associations the eariier
foimed one becomes relatively stronger, the greater the lapse of time since the
later one was learned.' In our own illustration the system used in B was imper-
fectly remembered when still in the shadow of learning C, but after the effects
of learning C had had a week to die down, the B system recovered, unfoitii-
nately for the subject, in the wrong series.
Forms II. This series has three tall figures, distributed near the middle
and on or near the ends. In learning, the series was balanced about them and
on one occasion Fig. 5 was put in the middle place. After two weeks the sub-
ject has forgotten the exceptions to the balanced scheme, as shown by her
arrangement, in which the three tall figures of the series are platxd at the ends
and in the middle. Fig. z is on the left, 5 in the middle and J on the right
end. The low intemiediate figures are not well remembered.
C. F. d. S. IV. Figs. 5 and 6 are exchanged. Possibly their similarity in
size was a partial cause. The other error was moving Fig. 1 to the right of
Fig. 7, of which no explanation other than simply memory-fading is offered.
Both errors in the final test only
Cols. II. Many errors in final test. No explanation.
Cols. 1. Final test. Again the arrangement is chaotic. Bri^t colots (red
and green) are erroneouslyput in the middle where they were in the three other
color series previously learned.
Col. Sizes A. The final test is badly mixed. The subject places only one
teim correctly, — 2 red orange. 4 blue green and 3 blue are exchanged. They
are next to each other in size and similar in color.
C. F. d. S. I. A single exchange of adjacents, Figs. 1 and 3.
C. F. d. S. II. Two exchanges of adjacents. Figs. 2 and 3, and 4 and 5.
Shows interferenceof other series: Fig 6 (window)' is put in ist place, occupied
inC. F.d.S. Ill (which preceded the present series with this subject) by a figure
of the same shape, but different color and size. Fig. i (slender vase) is put in
6th place as in Forms B, seen i day before.
Col. Sizes B. Three errors. Ends, blue and orange red, are exchanged,
due, the subjea says, to Cols. A, where a similar blue and red were on the ends.
Latter series not seen for 30 days. Orange yellow moved to the right of the
term belonging in 6th place. Reason not known.
' Miiller and Pilzecker.: Ztsch. f. Psych., Erganzungsbd. i, pp. 124 and 13S.
' These names are inventions of the operator.
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INFLUENCE OP COMPLEXITT AND DISSlidlLARITr ON MEMORT. 83
Cols, B. Exchange of the two tenns considered colorless or 'dead' by the
subject, A-yellow light and nann gray no. t.
Col. Forms I- All correct.
Forms B. An exchange of two figures adjacent and relatively veiy similar
in shape, Figs. 4 and 5 (inegular octagon and double crescent).
Sizes A. Another typical illustration of the schemes used by all the subjects
in the sizes of the simultaneous set. The correct order was 5416372. Her
system consisted, she says, ofthree'slcy-lines:' the first a descending one formed
by the terms 541, the second an ascending one fbrmed by the terms 167, the
third an ascending and descending one formed by the three smallest terms.
Despite the small total area of the series and consequently greater difficulty
in disciiminating the terms the system served its purpose pretty well. After
13 days and many series learned in the interval the subjea got the whole series
correct except a single exchange, the smallest and third smallest. She remem-
bered and used the system in reconstruction, but forgot the third 'sky-line.'
Col. Forms III. Influence of an introspection series given two and ane^alf
months before causes the subject to put Fig. 5 (inverted hat) in ist place, where
a figure of the same shape and size, but red instead of yellow had stood. The
other errors are displacements caused by this change.
Col. Forms. IV. All correct.
Col. Forms II. Poorly recalled and no special reason evident.
Sizes I. Same result as in Col. Forms II.
Forms A. Its mediocre retention is explicable on the basis of its extremely
short learning time, 10 sees. The equal-arraed cross, Fig. 3, is put in 5th
place, where the larger long blue cross was in C. F. d. S. II, 20 days before.
The other errora are exchanges of adjacents.
Forms III. In learning, a similarity between Figs. 6 and 7 and the number
10 was noticed. In final test Fig. 4 took the place of Fig. 6 in this idea. This
broug^ Figs. 3 and 5 together forming an unnatural looking low 'sky-line'
at this point, which R broke by putting Fig. 2 betvreen Figs. 3 and 5. The
two latter were also transposed. Note their similarity.
Col. Sizes III. In leatntng, the only error was an exchange of 6 and 7,
which are not only similar to each other in size (and in color to this subject),
but are also similar to the two largest areas of Sizes II (learned at the same
time) in respect to the positions occupied. The exchange was a copy of the
positions of 6 and 7 in the other series. Same ent>r repeated in the final test,
and also made by the subject next to be discussed.
Sizes II. Confused with the series just mentioned. In final test 6 and 7
were placed as they should have been in that series. Funher errors io this
series were moving 4 to left end and 1 to a place in the middle, both in imita-
tion of Col. Sizes III. The remaining errors cannot be traced.
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84 HARFET ANDXBF PETBKSON.
Cols. III. Her learning scheme wms: 'group ofthe left three were pronounceil
colors, yellow first, purple and red next, the last two a displeasing conabina-
tion. Group of the right three consists of a pale one ^teen ttnt) followed hf
two neutral colors. Blue associated with middle, a conspicuous position.*
In final test the left three were correctly recalled, but green gray was put in
the middle, with which place a gray had been connected in the week interven-
ing between the learning and final test of this series (viz: in Cols. IV). The
cue for the light three was forgotten.
Sizes III. Too poorly recalled to analyze. The left three have the regu-
lariy increasing size arrangement of the original, but do not begin with the
ezaaly correct size.
Col. Sizes IV. An ahnost complete copy of her last week's amngemcnt of
Col. Sizes 111, which she had recalled unc<Hnmonly well. The order there
was 3^/55172 instead of 347S'^- The order here was 346527/. The only
difference is an exchange of the two smallest. This is very different from
what the series should be, viz: 3162547.
Sizes IV. Too pooriy recalled to analyze. Her arrangement is similar in
a general way to the original in the fact that each wing consists of a large one
flanked by smaller ones, but the wings are exchanged.
Forms IV. In final test exchange of Figs. 5 and 6, due to the identity of
Fig. 7 with a part of Fig. 5. The confusion of similars most frequently shows
itself by an exchange, partial or complete, but it seettu not unlikely that at
other rimes it results in bringing together the terms confused. This is very
plainly the case here and in Cols. IV with the next subject, N. The remaining
error in Forms IV was an exchange of Figs. ■ and 3.
Cols. IV. In learning, red and green in 3d and 5th places, with gray between
them, formed a group. The complementary character of red and green, noted
by the subject, is both a help and a risk. They were exchanged once in learn-
ing, and in final test green is again put in place of red, the latter being dis-
placed ro zd place. Tlie other error consists in putting blue tint in 6th place,
where R had wrongly put a similar color last week. (Green blue in Cols. III.)
Suhjtef N.
Cols. A. Influenced by Cols. II learned the week before, three colon being
placed as were similar cobrs in that series. Blue is moved from 1st ro 3d
place, red from 7th to 5th and green from 5th to 6th. The other errors result
from these displacements.
Forms I. Exchange of adjacents, Figs. 4 and 5.
In discussing four of the series immediately following this chronological
table will be of service.
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INPLVENCB OF COMPLBXITr AND DISSIUILJKITr ON MEMOHr. %$
7th week. Learned Sizes B and Col. Sizes I.
8th week. Learned Sizes C and Co). Sizes II.
9th week. Final test of Sizes B and Col. Sizes I.
loth week. Final test of Sizes C and Col. Sizes II.
Sizes B. The correct order is 3416275. In final test the subject gave
3451726, — an exchange of sizes 6 and 7, and a removal of 5 to 3d place. The
tatter error gives a longer 'sky-line' in the first three temis, a peculiarity which
may have been due to Sizes C learned the preceding week. Both the peculiar
shape of the tenns in this latter series and their order (26, ^57, 13) emphasized
lines ascending to the ri^t. All of the subjects spoke of this and considered
it rendered the series easier.
Col. Sizes I. Same erroneous idea of pronounced upward slope in the final
lest of this series. Instead of the correct order, 2317645, 3457126 is given.
From the point of view of size this cannot be anything else than two upward
C. F. d. S. 111. Exchange of Figs. 5 and 7. No similarity.
Forms II. Two exchanges of similar forms, Figs. 2 and 5, and 3 and 6.
C. F. d. S. IV. Fig. 8, a small inveited hat, moved to the left of Fip. 4
and 5. No reason apparent.
Co). Sizes 'II. Final test was the same as in Sizes B, with a slight change.
Here it is 2351746. There it was 3451726,
Sizes C. In the final test the subject's arrangement was 3451726, the correct
order being 2645713. This is exactly the same mixture of B and C which the
subject employed in the final test of B, a week before.
Col. Forms IV. One displacement. Fig. 6 moved to the left of Fig. 4.
Cots. II. All correct, — very unusual. His scheme was: *The heaviest (red)
with the two lightest (yellow and green tint 1) on either side, were next to the
right end (4th to 6th places). Of the remainder a li^t one (orange red tint 2)
was on the left end followed by two heavy ones. The one in 7th place was
correctly placed by being left over after the others had been arranged.'
Cols. 1 and B. I preceded B a week in learning. In final test I shows
plainly the influence of subsequenriy learning B. The only error is a removal
of green yellow and red orange shade from 6th and 7th places to 2d and 3d,
and a consequent rightward displacement of 2-5. Hiis is approximately the
position of a bri^t red and yellow in B, namely, 3d and 4th positions. B,
however, is also affected in its final test the next week. The interference is
mutual. Aside from an exchange of adjacents (5th and 6th) the only error
is a removal of green from 7th to 2d place where a bright green stood in I.
Col. Sizes A. The errors are due to a confusion of terms within the series,
similar to each other in size and color. All of the subjects experienced thie
difficulty. The similarities in color constituted a defect in the series, and
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86 HARVBr ANDREW PETERSON.
were one of the reasons why it was rejected from the regular series. In the
case of this subject the error? were an exchange of 3 blue and 4 blue green,
and of 5 green tint and 6 A-green yellow.
C. F. d. S. I. Two exchanges of adjacent^.
C. F. d. S. II. This series shows interference of other series. Only the 1st
and 4th are correctly placed. Fig. 7 (spire) is moved to second place occupied
by a figure of the same shape but different color and larger in Col. Forms II
seen $ days before . Fig. 5 (tall cross) is put in 3d place occupied by a maltese
cross of a very different color and size in C F. d. S. IV. Fig. 2 (irademart) is
put in 6th place. The same figure but very much larger and of slightly dif'
ferent color had been in 7th place in C. F. d. S. IV. Fig. 3 (pin-wheel) is
put in 7th place where a figure of the same shape but diFerent color and site
had been in Forms II. C. F. d. S. IV. and Forms II. were last seen 31 days
Col. Sizes B. Recall too poor to analyze.
Forms B. Fig. 4 moved to ist and Fig. 7 to 4th place. No explanation.
Sizes A. Exchange of sizes 1 and 3, and 4 and 5.
Col. Forms I. Exchange of adjacent Figs. 4 and 5.
Col. Forms 11. All correct. The subjea said: "Figs, 3, 4, and 5 were
recalled by the appearance of the three as a group. Figs, i and 7 were asso-
ciated with their positions, and Figs. 2 and 6 were contrasted with each other
and associated with their positions.
Forms A. Interference of other series. Fig. 7 (wide vase) put in firw place
where a slender vase of different color had been in C, F. d. S. II 12 days before.
Exchange of Fip. 5 and 6. Fig. 3 (equal-armed cross) put in 7th place for
no apparent reason.
Sizes I. Exactly the same arrangement as was given for Sizes C 43 days
Sizes II. In learning the only error was arranging the series once in the
exact arrangement of Col. Sizes III. Despite the correction which it had
received, the same mistake was made in final test, the only alteration being
an inversion of the last two terms.
Col. Sizes III. An illustration of the fact that the interference is always
mutual. This series and Sizes I], learned at the same time, were confused
with each other. The other series fared the worst, but in the final test of this
series, 6 and 7 were arranged as they were in that series. There was also an
inversion of the last two terms, as in Sizes II.
Col. Forms III. Fig. 5 (inverted hat) put in ist place, occupied by a figure
of the same shape and size, but different color, thtee months before in an intro-
spection series. The only other error, aside from the righrward displacement
of Figs. I, 2 and 3, was an exchange of the similar figures, 4 and 6 (tombstone
and knobbed oblong).
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INFLUENCE OF COMPLEXITr AND DISSIUILARITY ON MEiiOSr. 87
Forms III. One error in final test, an exchange of the obviously similar
figures, 3 and 5 (pentagon and pentagon with curved upper sides).
Colors III. The errors were two exchanges; one of green yellow and orange
yellow, similar colon, the other of colors not similar. The association of a
smaller figure of the same color as one of them with the place where one of
these two is put, may have been the cause. The interval was a week.
Sizes 111. In final test the arrangement is quite similar to the correa order
in a general way, but not in detail. Instead of 2451376 is given 3561274.
This series and the next two are good illustrations of interference within a
series due to poor perceptual discrimination, the kind which Ranschburg found
in his six-place numbers. The very fact that the arrangement is similar only
in its general contour as a whole shows incomplete perceptual discrimination
of similar things, of the kind that he found.
Sizes IV. Confused with Sizes 111, learned at the same rime. Once in
learning it was given as 3461175, the correct order of Sizes 111 being 2451376.
The only other error made in learning was a removal of 3 from one end to the other.
In the final test there was a general resemblance to the correct order. 3741165
is given in place of 4761253. It is true that the correct orders of III and IV
somewhat resemble each other.but in thefbrmerthetwolargestareonthe right,
while in the latter they are on the left end. In the final arrangement of IV,
the largest is back in place.
Col. Sizes IV. 1 and 4 exchanged in final test,due to an exchange of 3 and
4 in learning. Cf. their posirions in the correct order, 3162547.
Fortns IV. Adjacent Figs. 2 and 3 exchanged in final test.
Col. Forms IV. Figs. 5 and 7 exchanged. No similarity.
Cols. IV. Too poorly recalled to analyze. Black, ist place, and gray, 4ih
place, moved to 3d and 2d places respeaively, — an instance of similars brought
together.
There were also 6 exchanges of numbers belonging to sizes nearest each
other in area, which occurred during the learning of some of the above series,
and which have not been heretofore mentioned.
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Monograph Supplements
VaL XU Juairr, Kll
Na. I Wkalt N*. H
THE
Psychological Review
EDITED ay
JOHN B. WATSON
cr JoHHi HoniMi UMinMnrT
JAMES R. ANOELL
UHi*»urt or Chkaoo
(EJtUf ■/ ih, FijcMipiJ IHt-*pmfk,)
Studies in Melody
W. Van Dyke Bingham
Instructor in Educational Piycholoty, Teachers CoUege,
Columbia Univenitr
THE REVIEW PUBLISHING COMPANY
41 NORTH QUEEN ST., LANCASTER, PA.
AND BALTIMORE, MD.
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PREFACE.
In the first portion of this monogra[^ are presented the
fcsults of investigations made in the psychological labora-
twy of the University of Chicago during the years 1905-07.
The experiments which form the basis of the remainder of the
work were carried on during the year 1907-08 in the Harvard
psychological laboratory.
To the directors of these two laboratories, Professor James
Rowland Angell and Professor Hugo Munsterberg, the writer
desires to express his gratitude for patient counsel and stimu-
lating criticism. He wishes also to acknowlei^ his obliga-
tion to the fellow-students of experimental psychol<^y, who,
in the capacity of observers, made possible the prosecution of
these studies.
To the investigations of Professor R. H. Stetson in the
field of rhythm the writer owes the method of attack employed
in studying the relationships of muscular movement to the
melody experience ; and the outline of a motor theory of melody
with which the present study is brought to a close is obviously
the outgrowth of su^estions from Professor Stetson's impor-
tant publications. Indebtedness to Professor Max Meyer is
likewise evident, and nowhere more plainly than in those pas-
sages which express disagreement with his views.
My (XJntroversy with Professor Meyer is ih part made
necessary because of what seems to me to be an equivocal use of
the term 'tonal relationship' on his part: and lesta similar ambig-
uity creep in to vitiate the discussions of the following pages,
1 have taken pains in each instance to specify in which of its
two common meanings the term "relationship" is used. Musi-
dans speak of two tones as directly " related " when the ratios
of their vibration-rates are so simple that one tone is found
among the first five partials of the other, or, what amounts to
the same thing, when the two tones belong to a major triad,
the 'chord of nature.' The "feeling of relationship" is the
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experience of coherence, of 'belonging-togetherness,' which
characterizes the hearing of two successive tones of the sort
described. The question as to what pairs of tones arouse this
feeling of "relationship" must of course be answered not by an
arbitrary definition but by reference to the facts of experience.
Now it is perfectly evident that this particular kind of tonal
"relationship," arisii^ out of certain acoustical properties
of the sounds, is not the sole kind of relationship which may
bind tones together in our experience. Two tones may come
to be felt as related, in a way, merely because they have often
been heard together. Moreoverany two tones whatsoever, be
their ratios simple or complex, are felt tx> be related to each
other as higher and lower. Here the term relationship is used
in its ordinary broad, untechnical sense.
Whenever, in the following pages, the terms "relationship"
and "related" are employed in the technical sense, they are
enclosed in quotation marks; and where these marks are not
used, the reader is to understand that the broader, untech-
nical connotation is indicated.
What the musician designates as tone-color or timbre, I
have called by the usual psychological terms, clang-color, or
briefly, color.
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CONTENTS
Past I. TBe Muody Pkobum pagb
fi. Thx n&tuK of mdody, Tlutt usages of the term, cnneipooduig to three
distiiict mdodic phenontena. A ntelody is a succession of tones which
are not only related, but which also canstitute an esthetic unity, a whole , . t
(i. AnillustratioD 3
13. The melody problem: How can a series of discrete tonal stimuli generate
the experience of melodic unity? 4
14. Elements of melodic structure : actual duration of the sounds, pitch, color and
intensity S
Is. Relative duration, intensityand color 6
|6. Pitch relations, thejiMfiuKim: Melodic "relationship" direct and indirect;
pitch distancei definite and indefinite pitdi relationa; the phenomenon of
the falling inflection S
(7. The phenomenon of melodic trend : certain paiis of tones heard in succession
tad better on the upper tone, others on the lower. Lipps fonnulates these
factsinthe'lawof thepowersof 3.' His theoretical asaunqitions la
|8. Restatement of the melody problem and limitation of the present study to
eSectsof pitch 13
Past II: Thz Phxnohema 07 Melodic "Rzlattonship," and or Melodic
Trbkd.
{9. Previous experimental studies. Meyer finds melodies played with an Intona-
tion wfairJi admits the 7 ratio are preferred to the same melodies played in
the diatonic scale 15
1 10. Meyer's theory of melody. Melodic " relationahip " observable in intervals
involving the 7 ratio. Tlie 'complete scale' 17
|ii. Dangers arising from the vse of arithmetical ratios taeTpress"relationship."
Any given feeling of "relationship" is the property not of a single interval
abne, but of a whole zone of intervals 11
{11. First series of eiperiments on the phenomenon of melodic trend, or fiitality
in two-tone sequences. Method. Observers »3
I13. Discussion of results, (a) The trend of the different intervals cnmpaied 17
in. (£} The lecondtoneofa two-tone group isjudged to beafinal tone lessoften
than it is judged to be lacking in finality s8
(15. (e) A small preponderance exists in favoi of descending intervals as more
definitely final. Meyer's experiments on this point. Need of separating
effects of the falling inflection phenomenon from effects due to more
definite pitch relations 18
it6. (d) When i is the end-tone, effects of rising and falling inflection come
dearly to view. When a is the first tone, the number of affirmative judg-
ments of finality is nearly the same for ascending and for descending
intervals, bcinE less than one-fourth of the total in each case 30
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vi CONTENTS
{17. Final mmmary lends some support to Uie Lipps-Mcyer law, but numerous pagi
J18. FuitbcT experiments pi^t toward the 'law of the return,' and toirard the
fact that tonality, resting on a harmonic basis, determines melodic
trends even in two'tone sequences 33
$19. Third series of evperinents: When a definite tonality is in mind, the
trend of a two-tone sequenra is unifonuly toward one of the tones of
the tonic chord 3S
tao. The nature of 'tonality.' A tonality is an 'attitude,' probably motor at
■11. The effects of habituation 39
■12. Summary, and new formulaUonof problem 41
Past III. Eptbcts ov Melodic Stimuli xjtov Mitscdlak MovEttEHT.
{13. Apparatus for recording rate, amplitude and form of tapfung movement of
finger 43
(34. Method of procedure 46
(35. Observers: tests of tlieir musical ability; individual differences in natural
rate and form of tapping 46
)i6. Results. Records of tapping without stimulus or distraction 53
{37. Effect of auditory stimuli upon rate of tapping $4
JaS. Experiments with melodic stimuli: the perfect fourth. Characteristic vari-
ations of rate of tapping appear, which are different for the ascending and
the descending fourth 57
|]Q. Hypothecs regarding the significance of acceleratitHu and retardations of
rateof tapping S9
{30. Tbe hypothecs applied in detail to theresultsof experiments with ascending
and descending fourth 61
{31: And tested in the light of experiments with the perfect fifth, diminished fifth,
major third and minor Mxth 63
I33. A group of experiments with three-tone sequences. The 'retumi' the
octave 69
(33. Effects of a longer series of tones upon the rate of tapping 77
Past IV. Sdggestions Towakd a Motor Thzosy or Melodv.
{35. Sketch (A a motor theory of melodic unity. Motor phenomena of mel-
ody and of rhythm compared. Final summary
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THE MELODY PROBLEM.
Si. Neither musicians nor psycholcpgists are agreed as to
the meaning of the term melody. Divergent usj^, leading to
misunderstanding and dispute, has arisen because within the
range of melody experience there exist several distinguishable
mental phenomena, each of which has in turn been oinstrued
astheessential mark of a melody. Weinmann,'follQwii^Lipps>*
says that a melody is a unity, a whole, no mere succession of
tones. It is, further, an esthetic unity in which the con-
stituent tonal elements are subordinated to a single dominating
element, the tonic. This definition operates to limit the scope
of his study to such melody phenomena as those exhibited in
modem European diatonic music, since it a priori excludes the
possibility of melodies which lack tonality.
The doctrine of Lipps and his followers that esthetic unity
always involves the subordination of the separate elements of a
manifold to a single chief element is opposed by MeyeH. In
his view, the statement that a melody is a unity means
merely that we experience relationship between the tones.
Indeed Meyer defines melody in terms of relationship.* To say
that two tones are related and to say that they form a melody is
the same thing. Such a definition avoids a narrow conception
of melody. The scope of the term becomes much contracted,
however, by the technical meaning which Meyer attaches to the
term relationship. The essence of melody consists, for Meyer,
not in the experience of any kind of relationship whatever
between the successive tones, but in the experience of a very
' Friu Wejnmann : "Zur Stniktui der Melodie" Zeiii.f. PtychtA. 1904, 35, 340.
'Th. Lippa: " Zur Theorie der Melodie, " Zeili. /. PijvAirf. 1901,27, 337. Seeftlto
his Paychologische Studien, ite Aufl. 1903, 193 B.
'M. Meyec, " Unsdeotific Methods id Musical Esthetics." Jour, of Pkil.
Pfy.,andS.M. 1904, i, 711.
< Elements ol a PaychologicsJ Theoiy of Melody. Piych. Sev, 1900, 7, 146.
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1 IP. VAS DrZB BINGBAM.
Special and limited kind of relationship, namely that to which
the technical musical term "relationship" has oome to be
applied. This narrowing of the meaning of the term operates
to exclude from the realm of melody those songs of primitive
peoples in which V£^e and indefinite pitch intervals appear,
as well as the so-called melodies of speech.
Can we assent to Meyer's contention a^inst Weinmann
that melodic unity means nothing more than relationship
between the parts? The esthetic unity which characterizes
a melody does indeed involve experience of relationship among
the several tones; but this is not all. For example, it involves
also the experience of completeness. If the feeling of complete-
ness is destroyed, the 'unity' is shattered. Not merely tonal
relationship, but 'form' is necessary to constitute the esthetic
unity of a melody. Meyer's deed here is better than his word:
for throughout his investigations he searches for somethii^
more than mere "relationship" in his melodies, namely, for an
organization of relationships, a combination of related tones
ordered in one way rather than another, — arranged, indeed, so
that they generate not a mere consciousness that the elements
are related, but a perception that they are so related as to form
a complete structure, a whole.
There are then, three clearly distinguishable phenomena,
eadi one of which has been put forward as the peculiar differ-
entia of melody: (a) "relationship" between the constituent
tones; (6) esthetic unity or wholeness, such as distinguishes a
definite melodic phrase when contrasted with a mere fr^:ment
of melody, or which characterizes even more clearly a com-
plete melody that is brought into comparison with any portion
of itself; (c) tonality, or the dominance of the entire sequence
by a single tone, the tonic. Weinmann's definition stresses
the third of these phenomena: if there exists a song of some
alien people in which the preponderance of one tone over the
others fails to appear, such a song must be called by some
other name than melody. Meyer at the opposite extreme.
emphasizes only the phenomenon of "relationship." Wher-
ever "relationship" between successive tones is felt, a melody
exists, even though the succession be fr^;mentary and the
hearer be left in suspense, unsatisfied.
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STUDIES IN MELODY.
For the purpose of the present exposition, it has seemed best
in defining what shall be meant by a melody, to place emphasis
upon the second of these three phenomena, — upon the esthetic
unity, the wholeness, which characterizes the completed expe-
rience. This usage of the term is adopted with full realization
that it is not wholly unobjectionable. After such a definition,
how shall one speak of W^^ner 's ' endless melodies ? ' By what
name shall one describe the effect when in a Brahms chorus,
one of the middle voices for a few brief measures stands
prominently forth only to be lost to the ear again in a maze
of counterpoint? Is not this tonal group without distinguish-
able beginning or end a most delightful melody? It would
certainly be called a melody if, with Meyer, we had chosen to
make "relationship" the sole essential; but in the terminology
we have chosen, it must be called a melodic fr^ment, and not,
stricdy, a melody.
The matter of prime importance is, of course, to realize
that by whatever names they may be called, we are aanfronted
with three different phenomena — "relationship," phrase- or
period-unity, tonality — which, no matter how intimately they
may prove to be bound up t<^ether, are nevertheless in intro-
spection clearly distinguishable, and must not be confused.
§2. At the risk of incurring the charge of prolixity from
readers who are most at home in this field, I shall venture to
develop somewhat more fully what I mean by a melody, before
attempting to formulate explicitiy the melody problem.
Let the reader ask himself in what way his experience of a
melody differs from his experience of a mere succession of
musical sounds of varying pitch. Possibly he will reply that
the group of sounds that he calls a melody is more pleasii^.
But this agreeableness he will admit is not the essential char-
acter. One may, for example, upon hearing a flc^eolet of ob-
noxious tone quality find the whole experience disagreeable
and yet recognize that what he is hearing is a melody; or on
the other hand one may take delight in a perfectly random
series of sounds drawn from a beautifully voiced instrument.
Something other than the pleasurable affective aspect of the
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4 W. VAN DVKS BJSGBAU.
total experience must be present to differentiate the melody
from the non-metodic succession of pitches.
Upon further comparison of the two kinds of experience the
observer will notice that the sounds of the melody seem to be-
long together, to cohere, and to stand in such a relationship
each to the others that the entire series is felt to be a unity.
The tones of the non-melody, by contrast, are felt to be unre-
lated : they do not ' hang together' as it were. Or, even if one
discovers that some of the tones of the non-melodtc group
exhibit a close connection with some of the others, the group
as a whole is not a unity : it is felt to lack con^stency or internal
coherence, or continuity, or completeness.
An example will make more obvious this contrast between the
melody and the non-melody. I played to a group of moderately
musical observers the following simple succession of musical
sounds: cf^^^fd'<f. The tempo was slow, the duration of
the tones uniform. I then played a second series beginning on the
same tone and ending on the same tone, and employing the same
five degrees of pitch as the first but in a different order: (ff d* g'
^fif. The hearers repcH'ted that in the first group the sounds
seemed to follow each other naturally, cdierently, and in a way,
inevitably, and with the last sound the series seemed to come to a
definite close. Each element articulated with the otha^ and the
group as a whole was felt to be a unity. In other words, it was
judged to be a melody. But with the second series of tones the
hearers failed to discover this naturalness or inevitableness
about the order of the sounds. The pitch, they said, wands^
rather incoherendy and disconnectedly here and there. More-
over when the last sound was heard it failed to bring the feeling
of completeness, of finality, which characterized the close of the
former series. This sea>nd succession of times was jutted by
these observers to be no melody.
S5. Our definition of a melody places stress upon the experi-
ence of unity; but tt does not prejudge the question as to
whether this necessitates the subordination of all the elements
to one dominating 'monarch dement.' Neither does it imply
that the experience of definite "melodic relationships" (in the
technical sense of the term) is the sine qua non. A melody we
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STUDIgS IK MBU)Dr. S
shall define as a succession of musical sounds which is felt to con-
stitute an esthetic unity, a unity toward the establishment of
which the pitch relations of the successive tones contribute.'
The melody problem, then, is the proMem of explaining how a
series of discrete tonal stimuli can arouse this feeling of unity.
As a matter of fact any actual melody such as a gamin whistles
on the street or a Pawnee Indian sings to the dawn, gains its
unity, its coherence, its wholeness, through the combined oper-
ation of many factors. The factors of intensity and duration,
for example, are co6rdinate with pitch in the determination of
the total psychoas: tempo, liiythm, dynamic structure share
in determinii^ what the melody shall be. A brief analysis of
these factors will bring into prominence the particular phases
of the melody problem with which these studies are concerned.
§4 It is to be remembered that musical sounds can vary
one from another in only four ways: in duration, intensity,
dang-color (i. e., tone-quality or timbre) and pitch. But each of
these four aspects or attributes of the constituent tones affects
in a two-fold manner the nature of the melody. The total effect
is what it is, partly because of the relative duration, intensity,
pitch and color of the separate sounds employed, and partly
because of the actual pitch, intensity, duration and color. The
'actual duration' factor, for instance, is the tempo. The rela-
tive duration of all the sounds remaining constant, the nature
of the melody may be entirely altered merely by changing the
speed, i. e., the actual duration of the sounds. A familiar melody
played in an unusual tempo may be hardly recognizable, and
if the change of time is carried beyond certain limits In either
direction the melody is utterly destroyed, — it becomes a con-
fusion of noises or a broken succesaon of sounds without signifi-
cance or interest.
Similarly, the actual or 'absolute' pitch of a melody enters in
to make it what it is. The low rumbling melody with which
Gri^ begins the "Dance of the Trolls" in the first Peer Gynt
suite is almost a totally different thing when played in the twice-
accented octave, instead of three octaves lower.
' Hoc and thioughout Uw paper, whenever the lecbnical oonnoUtioD of the term
"rdttionihip" is indicated, the word is enclosed in double quotatioD iD»Aa.
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5 W. VAN DYKE
The difference which the actual clang-color makes is of course
at the basis of artistic orchestration of melodies and of oi^ati-
re^tration. When a theme given out by the oboe is repeated
by the violins we say it is the same melody, and yet it is not
wholly the same.
Fourthly, the dynamic factor, the actual loudness or softness
of the melody as a whole, remains to be mentioned as one of the
(xmtributors to the nature of the melody.
§5. These four factors taken in their actual or 'absolute'
aspects are, however, of very secondary significance as com-
pared with these same factors operating within the melody
itself to contrast and to bind together the separate tonal ele-
ments. With reference to the relative duration, pitch, etc., of
the individual tones, it will be convenient to treat of (*) the re-
lation of each tone to its immediate associates, and (ft) the
relation of the tone to the whole melody. (Cf. ac(x>mpanying
outiine).
a)Act<ul
b) Relative
i. Measure pattern
Rhythmical figuiatloD
u. Accel., Rit.,etc.
II. INTKNSITY
a) Actual
b) Rehtive
i. Accent, itreu, etc.
ii. CKSc,decresc,etc.
[II. COLOK
a) Actual
b) Relative
i.
ii.
IV. Pitch
a) Actual
(AbiidtiU pitch)
b) ReUtive
Relations of duration of the first sort are at the baas of the
measure-form and rhythmical figures, while accelerando and
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STVDISS IN MELODY.
ritardando illustrate the relations to a more inclusive group.
Rhythm is usually a result of the combination of intensity and
duration relations, although this is not always the case. Thus a
melody played on the organ or on a mechanical piano player
lacks variations of intensity of the separate tones.
In the case of the loudness factor, the former type of relation
determines the effects of accent, of stress; while the latter gives
dynamic form to the whole group, the crescendo-decrescendo
effects, etc.
The relative color of the separate tones has, in the enumer-
ation of the factors of melodic structure, usually been neglected.
But a priori, one would expect this attribute of tone-sensation,
as well as the others, to be of ^^ficance; and a posteriori, color
is found to be of vasdy greater importance to melody than one
might suppose who had never given the matter careful thought.
Tlie reason why this factor has been overlooked is that it usually
remains constant throughout the melody. Its presence as a
unifying factor first comes into evidence when an unwonted
change of color enters and makes itself felt as a disturbing ele-
ment: as when a singer is not skillful in passing from one
register of the voice to another, or a clarinetist meets a similar
difficulty in making the transition from the lower to the middle
register of his instrument. The changes in color which are thus
unwittingly or unavoidably introduced have their disintegrating
effect, be it never so slight, upon the melody. Among violinists
this is a well known fact, a commonplace. Even so slight a
change of color as is involved in the passage from one string to an-
other is reo^nized as of importance in artistic phrasing, and the
resources of technical proficiency are sometimes taxed in the ef-
fort to meet the requirements which this principle imposes. Such
a principle raises a prohibition against careless shifts of color,
and at the same time offers a positive aid to artistic phrasing, —
it enables the violinist to give to a group of tones a peculiar unity
of its own not otherwise obtainable. Surely such a factor in the
determination of melodic form as clang-color, — a factor which has
a recc^nized place in musical practice, — does not deserve to be
entirely neglected. A careful experimental study of the effects
and of the possible extent of alterations of color within the mel-
ody is a psycholc^cal desideratum.
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$ w. nm owa MnnadM.
§6. AU of the factors which have been discussed, the rela-
tive dang-oilor, loudness and duration of the sounds, have been
shown to contribute to the structural unity of a melody. But
not all of these taken together are sufficient to make a melody.
The essential factor is still lacking, namely the pitch relations.
A sequence of tones of the proper relative loudness and duration
to constitute a vigorous rhythm would not be called a melody if
the pitoh of the tones were either unifcvm or random.
The pitch, too, of each tone bears certain relations to the
group of tones as a whole. This makes pos^ble sudi phenmn-
ena as tonality, of which it will be necessary to treat in due
time. At present let us focus attention upon the relations which
may exist between individual tones.
These relations between tone and tone are of several distinct
tj'pes. That type which has received fullest treatment at the
hands of the mudcal theorist is the one which has appropriated
to itself as a technical term the word "relationship." Twoccm-
secutive tones were said by Helmholtz' to be "directiy related"
if they form a perfectiy consonant interval, in which case one
of the clearly perceptible upper partials of the first is identical
with one of the second; while to be "indirectiy related" the two
tones must each stand in some such direct "relationship" to a
common third tone. This theory of "relationship" was used
by him tg account for the melodic intervals of the diatonic
scale. To account for the appearance of chromatic intervals,
'accidentals', in melodies, Helmholtz further reo^nized a "rela-
tionship by propinquity"; the 'accidental,' he said, is 'related'
to its neighbor by the mere fact of nearness. The fundamentally
important type of "relationship" was, however, of the other
sort; and since it had a basis in the physical laws of vitn^ting
bodies, it naturally was described in terms of ratios of vibration
rates. Like the phenomenon of consonance with which it is
closely allied, direct "relationship" seemed to be dependent
upon the partial identity of overtones which exists among
" related "tones.
What now is the psychological phenomenon of which these
physical facts seem to be the origin? In what way does one's
' tl.iMaihfHU,StnsalHms of Tone, tt. by ElIU, 1S95, 156 and 350.
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STUDIES IN MBLODr.
experience of a pjiir of "related" tones differ from that of a
pair of "unrelated" tones? The difference is easily felt, but
difficult to put into words. I shall here merely quote some
more or less descriptive phrases from the records of my observ-
ers. When two " related " tones are heard in succesaon they are
felt to 'oAere', to 'belong together', to 'articulate', to 'form
parts of a larger whole.' "Unrelated" tones do not so behave.
Rather they are felt to 'fall apart', to 'be unrelated'; 'they do
not seem to belong to the same melody.' Tones at an interval
of a major third exhibit a strong melodic "relationship." If
the interval isincreased bya quarter of a tone the "relationship"
disappears. This phenomenon of "relationship" is not to be con-
fused with that of consonance. The dissonant major second, for
instance, is an interval whose tones exhibit melodic " relation-
ship." What the significant connection is which exists between
melodic "relationship" and consonance will be pointed out
later.
Another type of relation which exists between the successive
tones of a melodic interval may be called the relation of pitch
distance. As regards their pitch all tones range themselves in
a one-dimen^onal series, as higher or lower; and the relative
position of two tones in this series finds its conscious represen*
tative in this feeling of pitch distance. Thus, the tone ^ is
felt to be at a certain pitch distance from c'; while its distance
from d' is felt to be not so great. It is at oncx perceived that
one's consciousness of the distance-relation between two tones
is clearly distinguishable from one's consciousness of their con-
sonance or of their "relationship."
It will be found useful to distinguish 'definite' from what
may be called ' indefinite' pitch relations. The former are char-
acteristic of all melodies which employ the definite intervals of
a fixed scale. Some kind of 'indefinite' pitch relation must be
experienced by that peculiar type of unmusical person who has
no exact sense for intervals, but who enjoys hearing himself
sing, and who can sing simple melodies in perfect time, and with
so much sense for pitch relations as is shown in ascending when
the melody should ascend, and then descending when the
course of the melody takes a downward turn. The pitch-out-
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lo W. VAN D7KR BISGBAM.
line or melodic curve of his soi^ corresponds in a vague, gen-
eral way with the pitch-outline of the melody imitated, and in-so-
far it betrays some kind of a sense for pitch relationship. These
'indefinite' pitch relations are characteristic of certain primi-
tive melodies.! Jhey also are of vast importance in the so-called
melodies of speech. Indeed, the infinite variety of delicately
expressive inflections which enrich our spoken intercourse must
be recognized as based upon pitch relations of this 'indeiinite'
kind. The gross difference between the rmag interrogative
inflection and the falling assertatory is the most obvious example
of this type of melodic relationship. The mental effects pro-
duced by mere rise in pitch have been described by Meyer in
terms of effects upon the attention.
A rise ID pitch causes the hearer's attention to become strained, and
the more so, the steeper the ascent, if I may use this expression. A (all
in pitch, on the other tiand, causes a relaxation of attention, a cessation of
mental activity The same strain and relaxation of atten-
tion is to be found in music. The normal end of a mental process is,
of course, characterized not by strained, but by relaxed attention; for
strained attention means continued mental activity. It is natural
therefore that a melody ends with a falling inflection. ... *
We shall have occasion frequentiy to ref^ to the significance
for the melody problem of this "phenomenon of the falling
inflection."
§7. If one carefully examines different mdodic intervals to
discov^* whether there may not be still other types of relation,
he will probably disclose to himself a phenomenon which has
received much attention at the hands of certain writers. He will
notice that many melodic intervals ediibit a peculiar character
which shows itself as a tendency for us to prefer one of the two tones
as an end tone. The interval of the minor third, whose tones
have the vibration ratio of 5:6, possesses no such attribute:
one acquiesces indifferenUy in either the upper or the lower as a
final tone. Neither tone has any very poative characteristics
of finality about it. Not so, however, with the perfect fifth
(2:3). If one hears it as an ascendir^ interval, he is dissatis-
' Cf., B. I. Gilmao, "Hcqri Songs," Joui. of Am. Ethnol. and ArcheoL iqoS, 5,
14 uid 134.
* Am. Jovr. Psych., 1903 , 14, 456.
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fied, uneasy, and under more or less tension until he hears the
first tone over £^:ain. But if it is a descending tif th which he hears
there is acquiescence, satisfaction, repose, and no desire to hear
the first tone a second time. One may say that one of these
tones stands to' the other in the relationship of 'tonic', or end-
tone. This aspect of musical intervals will be called by the
present writer their melodic trend.
Observation of this phenomenon as it shows itself in inter-
vals of relatively simple vibration ratio has led some theorists,
notably LIpps and his followers, to attach great importance to
the 2 ratio. They find, for example, that the trend of the fourth
(34) is very decidedly toward its upper tone as a final tone; of
the major third (4:5), toward the lower; while the minor third
(5 .-6) exhibits no noticeable trend whatever. The trend of the
major second (8:9) is toward the lower, and of the minor second
(15:16) toward the higher tone. Among the wider intervals,
where the reader may perhaps feel that the phenomenon is not
always so distinctly and unambiguously manifest, it is nev^-
theless held that the minor sixth (5:8) and the minor seventh
(9:16) trend upward and the major seventh (8:15) downward,
while the major ^th (3:5) shows no trend toward either upper
or lower tone.'
It will be seen that in the case of every one of these 'pure'
intervals the trend is toward that tone whose rate is a pure
power of 2 ; 2 always becomes the tonic. Where neither rate is
a pure power of 2, no trend is discovered. These phenomena
have been grouped by Lipps under what he calls the 'law of the
number 2.'
KQrzer gesa^t: — Treffen Tone zusammen, die sich zueinander ver-
haiten wie 3°: 3, 5, 7 usw., so besteht cine natiirliche Tendenz der letz-
teien zu den ersteren Mn; es besteht eine Tendenz der innereo Bewegung,
in den ersteren zur Ruhe zu kommen. Jene "suchen" diese als ihre
natiirliche Basis, als ihien natOrlicIien Schwerpunkt, als ibr natUrliches
Gravitationszentrum .
Dies ist naturgemEss um so mehr der Fall, je kleiner das (o) ist.
' These statements of typical trends are not completely in harmony with the results
of the experiments described below. Differences are most in evidence in the case of
the major and minor sevenths. See p. a^J.
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tt W. VAN OrKB BIKGBAM.
(o) istaberamkleiiisten, wenn es gldch o ist. Und 3°istgldch i. D.h.
die vollkommenste Ruhelage und das letzte Gravitationszeatrutn
solcher Tone bleibt immer der absolute Gnmdrhythmus.'
Upon this law of the compelling, dominatii^ character of
the 3 ratio, ti^ther with the principle that melodic "relation-
ship" is closer the simpler the ratios, Lipps grounds his theory
that a melody is a structure which gains its esthetic unity
through the subordination of all its elem^ts to one over-master-
ing ground-ratio, the tonic. This theory has been elaborated,
in its application to modem European music, in admirable
detail by Weinmann,* and defended vigorously by the author
himself.*
In undertaking to explain v/hy ttus phenomenon of melodic
trend toward the power of 2 should manifest itself, Lipps makes
one fundamental assumption, the assumption
that to the rhythm of the physical vibrations which generate a tone
there corresponds an analogous rhythm in the accompanying ptXKXSses
of tone-sensation, or in the accompanying change of psychic or central
conditions; that thus the psychic or central process of tone sensation is
separated into a succession of einnents or elementary partial processes
analogous to the succession of physical partial processes, i. e., to the single
sound waves.'
Such a correspondence between the nature of central proces-
ses and the physical processes which arouse them, Lipps has
found it necessary to postulate not merely in therealm of audition,
but throughout the range of sensory experience. Esthetic
pleasure results from inner harmony of our mental (or cen-
tral) energies. A color-contrast is beautiful if there is a sub-
conscious apprehension of the simplicity of the combination of
the ether vibrations.
In the present state of total ignorance with reference to the
intimate nature of central processes no attempt can be made
' Lipps. Psyckolopsche Studitn, i Aufl., 1905, 195. An identical foimulation ii
given in liis GrundUtung der Atslhetik, 190J, 465.
'F, Weionuum, "Ziw Slnictiir der Melodie. Ztits. f. Psyehel., 1904, J5. 34*-379
and 401-453- -
'Cf.,eipedtl&y,Piyehohgisehe Studitn, igjjT-
' Zeits. f. Ptyckol., 1901, 27, Ji8.
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STUDIES IK MBU3DT. Ij
either to establish or to disprove such an assumption. By
those who cannot follow Lipps in his bold hypothesis, his theory
of the number 2 must be viewed merely as a description, not
an explanation, of the facts.
Weinmann undertakes to buttress this theory of the basic
nature of 'duality' in vibration-ratios by reminding the reader
that 'double rhythm' is the original rhythm, the simplest, the
most natural, etc.' But this is an argument from sheer analogy;
for the experience of rhythm in the ordinary sense of the word
has nothing whatever in common with the unpermved micro-
rbythm of Lipps' assumption. One is a phenomenon open to
introspection, observation and experimental study: the other is
hidden, unknown, hypothetical.
Even though one may not relish such a theory as that of
Lipps and Weinmann, and though one may be inclined to doubt
the adequacy of their formulation of the facts by means of the
law of the number 2, neverthdess the phenomena of melodic
trend remain and must be reckoned with. Why is it that some
melodic intervals seem to end better on the upper tone and others
on the lower, while with still others it is a matter of iodiiference
which of the two tones comes last? Why is a risii^ fourth more
'complete' than a riang fifth? Why does an ascending major
second create a demand to hear the first tone over a^n, while
an ascending minor second does not?
$8. No further attempt will here be made to enumerate with
greater completeness the various mental phenomena which
flow from the facts of pitch relationship. Only those have been
mentioned which are of especial significance for these studies:
pitch distance, definite melodic "relationship," indefinite
pitch relations, consonance, melodic trend, the phenomenon
of the falling inflection. We shall later have occasion to ask
which of these phenomena are primary and which secondary or
derived.
Our survey of the factors — of pitch, duration, clang-color
and intenaty relations — which contribute to the structure of
a melody, makes possible a more definite formulation of the
limited purpose of these studies.
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14 W. VAlt or KB BtHGBAU.
How the pitch relations of a s^es of discrete musical sounds
may operate to weld these sounds into the organic whole which
we perceive as a melody, — this is the core of the melody problem,
and to this primary phase of the subject our present investiga-
tion will be stricdy limited. To this end we shall consider
pitch alone, and abstract'as far as possiUe from all conadera-
tions of rhythmic figuration, accent, force, tempo, tone quality,
etc., although these various factors would all demand attention
in any account of the melody problem which aimed at comi^te-
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THE PHENOMENA OF MELODIC "RELATIONSHIP" AND OF MELODIC
TREND.
$9. The reports of previous experimeDtation spediicaliy
directed toward the mdody problem are few in number.
One of the most or^:inal and si^gestive workers has been
Professor Meyer, and a survey of his contributions will serve to
bring our own problem more clearly to view.
The first of Meyer's experimental investigations' led him to
reject the theory of the diatonic scale, and to develop a new
theory of melody. He used a reed organ specially constructed
so that in playing a melody the performer was enabled, for each
note of the printed score, to sdect any one of two or three tones
of nearly the same pitch. Thus after repeated trials he could
determine precisely what intonation of any particular melody
was most satisfactory.*
Meyer publt^ed his analysis of some thirteen melodies, giv-
ii^ the intonation of each which seemed to him to be the best
These include melodies of folk songs and chorals as well as melo-
dies from well known classical compo^tions. The reader is not
surprised to find that the preferred intonation does not coindde
with that of "equal temperament;" but neither does Meyer find
that the melodies are most satisfactory when played in the justly
intoned diatonic scale familiar to musical theorists. To be sure,
in the Ampler melodies, most of the [Htches in the pr^erred
intonation correspond exactly with the pitches when the melody
IS played in accordance with the diatonic scale. Some marked
exceptions appear, however. Meyer finds, for instance, that
*M. Meyer: "Etements of & Psychological Theory o( Melody." Ptych. Ra.,
1900, 7, 341-173. Reprinted mih Tevisloos and additioos ia "Coutribudons to ft
Psychologicftl Theoiy of Music," Unit, of UUsottri SttidUt, igot, 1, 1-80.
' Adescriptioa of the instrumeDt, irith diAgiamofarnuigemeDtof kejrsoa the duoubI
is found in the Zeits.f. Psychol- 190J, 33, igi.
.yGoogle
l6 W. ViN DYKE BINGEAU.
the 'fourth' is preferred flatter and the 'sixth' sharper than
diatonic intonation demands. To render the nature of these
differences more clear, reference may be made to the accom-
panying table.
[lA J7 30 3» 36 40 45 4*
Some corresponding f i 9/8 j/fl *l/W 3/* tl/i^ »s/8 »
pitches from Meyer's { 9/8 to/9 »i/»o V? 9/8 10/9 16/15
Complete S4:ale. I16 18 30 ii 14 17 30 3*
Dutonic scale 48546064 71 80 90 96
Meyer's 48 54 60 68 71 81 90 96
The first line of fractions shows the ratio between the vibration
rateofeachnoteof the diatonic scale and the vibration rate of the
key note. Reducing these fractions to a common denominator,
we obtain as the resulting numerators the numbers in the third
row of the table. These are the numbers usually employed to
express the relative pitch of the notes in the diatonic scale. (The
ratio between the vibration rate of each note and that of the
next note in the scale is given in the second line of fractions).
For com[>aTison with these, I have selected from Meyer's
'Complete Scale' those notes which are used in the simpler
melodies (see lines 4, 5 and 6 of the table).
It is to be noted, first, that the ratios in the diatonic scale
involve no prime number but 2, 3, and 5, whereas the other
scale employs the number 7 in its fourth. Thus, to tune/ in the
key of c one would not tune it a perfect fourth above c, but
would tune it at an interval of an harmonic or sub-minor seventh
(74) above the g below. Moreover the denominators of all
eight ratios from the newer scale are pure powers of 2 whereas
this is not the case with the fourth and sixth of the diatonic
scale. The amount of difference in pitch which is involved Is
shown in the last two lines of the table where the ratios of the
two scales are reduced to a common denominator for compari-
son.
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STUDIBS IN MSLOOr. 17
To understand the ^gnificance which attaches to these differ-
ences, and other more marked differences in intonation which
come to light in the more complex melodies, it is necessary to
examine two "laws of melody" which, if one follows Meyer, lie
at the ba^ of musical theory.
810. The first of Meyer's laws of melody may be called the
]a.vot melodic "relationship:" Only tones which are"related,"
directly or indirectly, can belong to the same melody. The
second, a law of melodic trend, is dmilar to Lipps' law of the
number 3.
We will give Meyer's own formulation of what he means by
the term "relationship."
When we hear successively two tones, the vibration rates of which are
to each other as 2:3, or briefly speaking, the tones 3 and 3, we notice
something not describable, which I shall call the rdalionship of these
tones. To understand what is meant hereby, the reader may listen to
the successive tones 7 and ti or ti and 10, in which cases be will notice
that the two tones have no rdatioo at all to each other.'
It is a fundamental contention with Meyer, — a contention
that will demand our critical scrutiny, — that this psychological
quality called "relationship" attaches only to pairs of tones
whose ratios are expressible in simple fractions involving no
prime number above 7.
That no relationship at all is to be observed with tones ie[^esented
by the prime numbers 11, 13, 17, 19, etc., leads to the oinclusion that
only tones represented by the prime numbers i, 3, 3, 5, 7, and their com-
posites possess that psychological property.*
lliis leads to the theory of what Meyer names ' the complete
scale.' Since none but related tones can belong to the same
melody, and since "relationship" seemstoexistonly between tones
represented by products of 3, 3, 5, and 7, the complete musical
scale, or the series of all the tones which may occur in a dngle
melody, is represented by the infinite series of all products of
the powers of 2, 3, 5, and 7 (p. 249). The beginnings of such a
scale, containing so many of these related products as were found
> Meyer: Ptyck. Rei., 1900, 346.
»0f.<., J47.
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1 8 W. VAN DVXB ttmGBAU.
to be needed in the analysis of the melodies he studied, are
given by Meyer in tabular form.
In maintaining that the 7 ratio exhibits the fundamental
mdodic qualities and must not be excluded from musical theory,
Meyer takes sharp issue with traditional treatments of the sub-
ject. Lipps and his followers who have done more than anyone
else tx) place the theory of melody on a baas of exact descriptive
formulation find no need of ratios involving prime factors
larger than 5. Other writers, as Helmholtz, Gumey and Stumpf
have also been content with the theory of the diatonic scale,
a scale whose ratios employ the numbers 2, 3, and 5, but not the
numba* 7. Against these, Meyer brings the charge that they
have been influenred primarily by considerations involving the
phenomena of harmony, and have failed to point out what facts
observable in melody justified them in excluding the number 7.
The facts as he finds them are that such melodic intervals as
the sub-minor sevtoth (4:7) the sub-minor fifth (5:7) the sep-
timal second (7:8), etc., do possess the pyscholt^cal quality of
"relationship;" and what isof more weight, he finds that melodies
played in his so-called complete scale, which admits the 7 ratio,
are preferred to the same melodies played according to the
diatonic scale.
Meyer has been subjected to criticism for publishing his
experiments and basing an elaborate theory upon them, when
the judgments of preference recorded are apparently those of a
single observer, namely, the author himself. Meyer admits the
force of these critidsms, but insists that even so much of induc-
tion and carefully systematized observation as this report of his
studiesembodied.has moreclaim upon the attention of a scientific
reader than all the great mass tA writing upon musical theory
which has no scientific, inductive ba^s whatever.
How does Meyer account for the phenomena of melodic
"relationship?" How does he explain the fact that we feel the
tones 2 and 3 to be "related" and the tones 11 and 10 "unre-
lated?" In contrast to Lipps he does not attempt to account
for the facts. On the other hand he frankly Eidmits that he is not
offering an ecplanation of the melody phenomena: for this, as
well as for an explanation of the facts of consonance we must
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STVDISS III UELODT. 19
await further light upon the nature of neural activity and the
action of the sense oi:gans. All that Meyer is attempting, then,
is to comprehen^vely describe the facts.
Hb first step toward this descriptive formulation has already
been mentioned. As a result of his examination of the phe-
nomenon of melodic "relationship" he dedded that all cases of
"relationship" are capable of bring expressed io relatively
ample fractions involving no prime factors except 2, 3, 5, and 7;
and consequently the 'complete scale' is limited to tones ex*
pressed in these numbers and their compounds. The second
step is the formulation of a law of melodic trend dmilar to, but
not identical with, that of Lipps:
Wben one of two related tones is a pure power of 2, we wish to have
this tone at the end of our succession of related tones, our melody.'
Expanded to cover melodies of more than two tones, the law
assumes the following form:
No hearer is satisfied if after having heard once or more often the
tonic a he does not find 3 finally at the end of the melody.'
In the elaboration of his theory Meyer utilizes two additional
principles. One of these is that among "related" tones there
exist different degrees of "relationship." The other principle
is that of all those intervals which possess a certain "relation-
ship" we have a decided preference for the smallest. The
detailed development of the theory based upon these principles
we shall not here undertake to summarize, but its foundations
we must pause to examine more closely. It is obvious that
there is need of conclusive evidence supporting the basic propo-
sition upon which the theory is erected, the proposition that
tones representable by the prime numbers up to and including
7 alone exhibit "relationship."
As evidence Meyer presents, as we have seen, two groups of
facts, one derived from an examination of separate intervals
and one from observation of the use in actual melodies of the 7
ratio. In both cases, as Wead'has pointed out in his penetrat-
' Unitersily of Uissouri Sludiei, t,g.
' L. c, n.
* C. K- Wead, Piyckolopcal Raita, 1900, 7, 400.
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30 W. VAN DYKE BISGBAU.
ing review of Meyer's work, the judgments recorded are appar-
ently those of a single observer, and he a man of harmonic
training. What indication is there that one who had never
become familiarwith anything comparable with our European
harmonic musical system would experience these elementary
"relationships?" "Nothing," says Wead, "can be more cer-
tain historically than that these relationships have been unrec-
ognized by most of the men throughout the ages who have
concerned themselves about music." One cannot avoid ask-
ing the question whether Meyer's deductions necessarily hold
for hearers of melody other than those who, like himself, have
long experienced the associations of modem European music.
A somewhat similar question arises regarding the effects of
practice in detecting these melodic "relationships."
Meyer leads us to understand that only after long and
careful observation did he decide that 5:7 and 7:8 exhibit
"relationship." In another connection he proves' that "rela-
tionships" not detected at first come later to be felt, upon
greater familiarity. This seems to place him in a dilemma.
May it not be that the familiarity breeds the " relationship? "
It would not be rash to hazard that if Meyer had chanced to
spend his early years in the Scottish Highlands it would never
have occurred to him to exclude 11 while admitting7 among the
prime factors of his 'complete scale ;' for in listening to the bag-
pipe he would have become accustomed to the interval li :i2,'
would have learned to reo^nize it accurately, and to feel
"relationship" between 11 and 12 as truly as between 15 and
16, or 7 and 8.
As long as the question remains unsettled regarding the
inclusion or exclusion of 7, 11, or any other ratio in making up
the list of elementary "relationships," a certain doubt will
remain regarding the validity of Meyer's experiments on the
intonation of actual melodies; for, in selecting the preferred
pitches the observer's choice of alternatives for each note, it
will be remembered, was limited to the two or three tones
' See below, p. 40.
■C/., A. J. Ellis: "OiitheMusia1ScalesofVuiou»Nattons,"/oiirMio/fi<5M;>e(7
of Artt, London, iSAs, 33, 499.
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STUDIES IN USLOOy. 31
available from the scale constructed out of products of 2, 3, 5,
and 7.
Instead of attempting here to settle this issue, let us ask
some further questions with reference to Meyer's two main
contentions. Is it true that only intervals the ratios of whose
vibration rates are expressible in small prime numbers mani-
fest the psychological quality of "relationship?" Is it a fact
that of two "related" tones whose ratio can be thus expressed,
the hearer always prefers as an end-tone that one which is a pure
power of 2?
5ll. First let us c»nsider the fact of melodic "relationship."
The major third is an interval which exhibits the character
of " relationship " very unambiguously. This is an interval whose
tones have the vibration ratio of 4:5. Now, what is the effect
when we listen to an interval just barely wider than this, say
the interval 400:501? It so happens that this interval exhibits
the "relationship" more clearly, if anything, than 4:5 did,'
although it is so nearly the same interval that those without
special training cannot tell the two apart. Suppose thb inter-
val to be made a trifle larger yet, so that it has the ratio 400:504.
Do the tones suddenly lose their character of "relationship?"
One would hardly expect them to do so. Pr^sely what does
otxur is, that as the width of the interval is gradually increased
it b^ns to change somewhat in character; but it remains a
major thiid, — not a satisfactory third to be sure, but neverthe-
less a third with the characteristic "reUUional" attributes of that
interval, — until it reaches nearly to the middle of the zone
which divides the major third from a perfect fourth.
The experimental evidence, if any is required, in support of
these statements, is easily obtained. The procedure adc^ted
by the writer was to determine the effect produced upon the
feeling of "relationship" by gradual but supra-Iiminal varia-
tions in the size of a melodic interval. Between the b and c'
of a harmonium six reeds were interpolated, giving seven inter-
vals, each of a magnitude of about 16 cents (t. e., hundredths of
< Stumpf and Meyer found that all of the consonant intervals kiger thftn a minor
thiid are preferred too large. C. Stumpf and M. Meyer, "Maassbcstimungeu Qber
die RcinbeJt coDsotuuterlntervalle." Zeits.f. Piyckol., 1898, iS.sti.
_Disil,zccl by Google
31 W. VAN BYKB BISGBAM.
an equally tempered semi-tone). Such an interval in this F^;ion
of the scale means a difference in ptteh of scarcely more than two
vibrations. It was thus possible to play any desired diatonic
interval and also any one of half a dozen intervals intermediate
in magnitude between it and the next larger interval. Only the
major third and the fourth were tested. The method was with-
out knowledge. The twelve observere were already familiar
with the phenomena of "relationship" and finality in two-tone
combinations. They were ignorant of the nature and purpose
of the experiment The observer was asked whether or not the
two tones played were "related, "and if the response was in the
affirmative the further question was put, r^:arding the com-
pleteness or incompleteness of the two-tone group.
It was found, with each of the twelve observers, that the
characteristic feeling of "relationship" was nearly always still
present when the interval had been increased (cm* diminished)
32 cents, (a third of an equally tempered semi-tone). The
characteristic feeling for the upper or the lower as an end-tone
also remained. An alteration, however, of 48 cents (roughly a
quarter of a tone) destroyed the feeling of "relationship" in
74 per cent of the 96 judgments.
In general, when a pure interval is gradually modified its
characteristic melodic qualities remain long after the interval
has lost the characteristic qualities, e. g. of consonance, which it
manifests when its two tones are heard simultaneously instead
of in succession. This fact ought to be of weight for any theory
of melody which lays emphasis upon the psychological quality
of felt "relationship." Since the ratio 34 has no monopoly
upon the characteristic "relational" qualities of the fourth, but
is rather only a modal ratio about which cluster an immense
numbo- of lai^er and smaller ratios manifesting in some meas-
ure identically the same psychological qualities, the use, with-
out qualification, of the symbol 34 to represent that particu-
lar kind of " relationship' ' is misleading.
What is true in this respect regarding the facts of "relation-
ship" is of course equally true regarding the facts of finality or
melodic trend.
It may be ui^ed that we are here confronted simply with the
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STUDIES IN MBLOOr. 23
common characteristic of perception, the modification of sen-
sory data by central processes so that these data may be apper-
ceived to the nearest available norm. Such tests as the above
then would merely measure the tendency of the listener to hear
different nearly equal intervals as the same pure interval, and
do not prove that the "relationship" of the fourth inheres in
any other ratio than 3: 4.
But such a view neglects the fact that when we are listening
to an interval slightly larger than 3-4, we may recognize it as
larger and still at the same time experience the feeling of "rela-
tionship" characteristic of the fourth. The "relationship,"
in other words, inheres not merely in the interval 3 4, but also
in intervals rect^nizably lai^er or smaller than the justly
intoned perfect fourth.
§12. We shall not, however, press this consideration. In-
stead we shall leave in abeyance the question regarding the range
of applicatHlity of the pure powers of 2 formula, and shall seek,
in the results of the experiments now to be described, the answers
to certain questions with reference to the melodic trend in inter-
vals with the simplest arithmetical ratios, — the intervab in
which we are led to expect that the phenomena will be most in
evidence. Does experiment establish the proposition that when
one of two related tones is a pure power of 2, we wish to have this
tone at the end, and that when neither of the related tones is a
pure power of 2, no preference is felt for either as an end-tone?
What is the relative strength of the trend in different two-tone
combinations? Do the simplest ratios exhibit it most definitely?
Do all observers feel it alike?
The method of the experiment was to present two tones in
succession, and ask, "Can you make this second tone a final
tone? Does this melody end?"'
The following series of ratios was used: 2:3, 5:6, 3:5, 15:16,
45^4, 4:5, 9:16, 3245. 8:9. 8:15, 5:8, 34. This series was given
in the 'double fatigue order,' both ascending and descendii^.
Ten of the twelve ratios are relatively simple. Two, the ai^-
' At tbe time when these experiments were planned, the experimenter was using
tlK tenn 'melody' in tbe sense in which Meyer uses it. When the word implies nothing
except "relatimship," it is entirely appropriate to speak of melodies of only two tone^
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1< IT. VAN DTKB BINGBAU.
mented fourth and diminished fifth (3245 and 45:64), in*
volve pure powers of 2 but are not simple, and were included
for purposes of comparison. Heavy Koenig forks mounted
on resonant* boxes and actuated by a rubber mallet were used
as the source of sound. Each tone was sounded for five seconds.
The range of pitch was limited to the once and twice accented
octaves, the lowest fork being the middle (f of 256 d. v. and the
highest the g* of 768 d. v. In arranging the series care was
taken that neither of the tones of any pair belonged to a tonality
which might have been su^ested by the interval preceding.
Eight persons served as observers in this series. None of
them would be classed as totally unmusical, and none of them
are "mu^dans," yet they represent, between these extremes,
a wide rangeof musical ability. All are familar with musical nota-
tion and sing or play some from note. W^th at least two of the
observers, there is a lack of interest in music, their skill at the
piano being a mechanical acquiation. Three of the observers
confessed to an acquaintance with the elements of harmony
and musical theory, but it was evident upon trial that their
theoretical knowledge was not concrete enough to exert any
influence upon their immediate judgments of musical intervals.
It may be remarked here that throughout these and also the later
&cperiments the observers gave unreasoned judgments, the
introspective records on this point confirming the opinion of
the writer based upon the manner of their replies. All the ob-
servers had had training in experimental |>sychology.
The accompanying table gives the affirmative, doubtful and
negative judgments of each of the eight observers with respect
to each of the melodic intervals used.
.'Google
STUDIES IK MBUODT.
TABLE NO. 1
inal
tow?
■
n™vAL
An.
Td.
BL
WL
Eo.
Dt.
He.
Yo.
TOIAl
UinoT Second, Ascending
DocendiKg
Uajor Second, Ascending
Descending
MinM TUid, Ascending
DcKending
Major Third, Ascending
(4:5)
Descending
Perfect Fourth Ascending
Descending
cending
(3= --45)
Descending
Affirmative
Doubtful
Negstive
AffirnuUve
Doubtful
Negative
Affirmative
Doubtful
Doubtful
Negative
Affinitive
Doubtful
Negative
Doubtful
Negative
Doubtful
NegaUve
Affirmative
Doubtful
Negative
Affinnative
Doubtful
Negative
Affirmative
Doubtful
Negative
Doubtful
Affirmative
3
4
4
4
4
3
^
4
3
4
4
3
4
3
4
4
3
3
4
3
4
3
4
4
4
^
3
4
'
J4
iS
DiBiiizcdb, Google
Diminished Fiftb, A>-
ccndiiig
(45*4)
Perfect Fifth, Ascending
(3-3)
Minor Sixth, AKmding
(S:8)
Major Siitb, Ascending
Minor Seventh, Ascend-
(9:16)
Major Seventh, Ascend-
ir. VAK DFKB BISCBAM.
Coat, ol TABLE So. 1
An. Td. Bl. Wl
Affirmative
Doubtful
Negative
Affirmative
Doubtful
N^ative
Affirmative
Doubtful
Ni^ative
Affirmative
Doubtful
Negative
Affirmative
Doubtful
Negative
I Rd. D|. I Un. Yo. win.
Affirmative
Doubtful
Negative
Affirmative
Doubtful
Negative
Affirmative
Doubtful
Negative
Affirmative
Doubtful
Negative
ASnnative
Doubtful
Negative
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STUDIES IN MELOOr. tj
§13. These results indicate that the descendii^ major third
(4:5) and the descending perfect fifth (2:3) exhibit more of the
quality of finality than any of the other two-tone combinations.
The one was judged definitely to end 28 times, and the other
26 times, out of a possible 32.
The other intervals showing more affirmative than negative
judgments are the ascending perfect fourth (34) with 21 affirm-
ative judgments; the descending major second (8:9) with 20;
the ascending minor second (15:16) with 17; and the asf^nding
minor sixth (5:8) with 14.
The diminished fifth (45 Aj.) — both ascending and descending
— and thedescendingminorsecond (15:16) each have the highest
number of negative judgments — 24. These are the intovals
that most clearly lack finality. The ascending major second is
next with 21 negative judgments, followed closely by the ascend-
ii^ and descending augmented fourth, minor third, minor seventh
and major seventh, and the ascending major third. The per-
centage of negative judgments of the as(%nding perfect fifth
and the descending perfect fourth is the smallest of any of the
intervals judged not to end.
The ascending minor seventh (9:16) and the descending major
seventh (8:15) are both judged to lack finality, contrary to the
law of the number 2, although their inversions, the major and
minor second, conform to the law. The ascending minor seventh
has only 7 affirmative judgments as compared with 19 n^;ative;
and the descending major seventh has 8 affirmative and 20
negative judgments.
What is the reason for the laige number of negative judgm^its
on these lai:ger intervals? One answer is, that die tones of these
wider intervals sometimes failed to arouse any feeling of "rela-
tionship." "Those two tones do not belong in the same melody."
"That second tone caimot be a final tone because it has no con-
nection whatever with the first" "No! The tones aren't
related." Such introspections were frequently given when the
wider intervals were used. These not highly muacal observers
experienced a sufficiently strong and definite feeling of "relation-
ship" in the case of such a small interval as 8:9, but found all
"relationship" lacking in the invasion of that samelnterval, 9:16.
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)8 W. VAN DTKB BIltCBAM.
This means that in formulating the facts c^ their mu»cal expe-
rience it would not be pennissible to do as Meyer has done, and
"omit the number 2 as a factor," or in otherwords to treat the
trend and the "relationship" in any interval as identical
with that of its inveraon.
S14. Three-fourths of the 34 combinations are judged not to
end more often than to end. The total number of judgments is
distributed as follows:
Affimutive as6 33
Doubtful 13s '8
Ncg&tive 377 «
If we leave out of con»deration the more complex intervals,
the augmented fourth and the dimini^ed fifth, the totals stand
as follows:
Affinutive 336 37
Doubtful lis 18
Negative 189 4S
From these facts it would seem that in general it is somewhat
harder to accept the second tone of a two-tone sequence as
fin£il than it is to judge it to be lacking in finaUty.
§15. Do the results of these experiments indicate that de-
scending intervals as such tend to cause the feding of finality?
To answer this question the data of Table 2 may be redistrib-
uted so that the totals for as<£nding and descending intervals
may be compared. Following are the totals for all the intervals
represented by simple ratios involving a power of 2, then for
the more complex intervals (augmented fourth and diminished
fifth) and the intervals whose ratios though simple involve no
power of 2, and finally for all twelve intervals combined.
Simple Ratios Involving a Power of 1:
Affirmative..
Dot^tful....
Negative....
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STUDIES IN MSLODT.
Gimplei Ratios, and Simple Ratios without a Power of i
Affirmative 19 93
Doubtful 18 14
Negative 81 6;
Totab for all Twelve Intervals:
Affiimative 118 31 138 36
Doubtful 67 17 68 18
Negative 199 %3 178 46
In each group, tones which are powers of 2 had the position
of first tone exactly as many times as they had the position
of final tone; consequendy it will not be far wrong to assume
that any effects due to the operation of the law of the powers of
2 are cancelled.
There is found, especially in the first of these three sum-
maries, some preponderance in favor of the descending intervals
as more definitely final and of the ascending intervals as lacking
in finality.
This effect of the fallii^ inflection has been made the object
of esqierimental determination by Meyer.'
Three tones of a reed organ were played a few times in irregular suc-
cession, ending on one of them. Then they were played in a similar way,
ending on another one; and lastly, ending on the third tone. This was
repeated until each subject had made up his mind and written down
which of these three endings was the most satisfactory to lum
Two classes of experiments must tie distinguished: one in wliich there
was no tonic effect among the three tones; and one in which there were
tonic effects. In the former case the three tones were represented by
thesymbolS3, 5,and 7;inthelatter,by 3,3, andg. [The tonese.^.and
7b'' standintheratioof 3:5:7; c,g and d would be represented in Meyer's
symbolism by 3, 3, and g.] . . . . The three tones of one experi-
ment were always within a single octave. Each of the three tones, how-
ever, liad an equal chance of exerting its influence, *. «., of being the
lowest of the three. (P. 4S8-)
Where there was no tonic effect, the lower tone, whichever
' Amer. Jour, Ptyck., 1903, 14, 456.
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W. VAN D7KB BINCHAU.
it happened to be, was preferred as an end tone, the totals
being 5 choices for the higher, 8 for the middle, and 17, or 57
per cent of the total, for the lower tone. In the other series,
one of the tones was a ' tonic' When this tone was also the
lowest tone it was preferred as the end-tone in 86 per cent of
the judgments. When it was the middle tone it received
70 per cent of the choices; and when it was the upper tone
only 7 per cent.
These are striking results and one wishes that these experi-
ments had been carried farther. Brief as they are, however,
they serve to emphasize that the effect of finality at the close
of a melody may be due in part to the operation of other
causes than the powers of z phenomenon.
It thus is obviously desirable, in discussing the meaning of
our own results, to separate as far as this is possible the finality
effect produced by the falling inflection from that which is
due to the more definite pitch relations of the tones.
§16. We shall first bring together the totals for those
simple intervals (Group S) whose ratios do not include a
pure power of 2, t. e., the minor third (5:6) and the major sixth
(3:5). The second summary will include the complex inter-
vals (Group C) involving powers of 2, t. e. the augmented
fourth (3245) and the diminished fifth (45:64). Then will
come the eight remaining intervals, all expressible in simple
ratios one of whose members is a pure power of 2. These lat-
ter it will be convenient to separate into those intervals in
which the 2 tone is the higher (Group H), and those in which
it is the lower (Group L).
Group S. Simple Ratios without a Power of i
Asceaditig
Affirmative. .
Doubtful....
N^atire —
Descending
Affirmative. ,
Doubtful. . . .
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STVDIBS IN URLODV.
Group C. Complex Ratios Involviog a Power of i
> ■ 4S « ■ 64 101*1 »K
AsceEtding
Affirmative 8 3 11
Doubtful 3 5 8
N^ative 31 14 45
Desceading
Affirto&tive 6 3 9
Doubtful 7 5 i>
Negative ig 14 43
Sim[de Ratios Involving a Power of 1:
Group H. (Higher lone a Power of i.)
Ascending
Affirmative 17 31 14 7 59 46
Doubtful 46 6 6 II t?
Negative 11 j " '0 47 37
Descending
Affirmative 4 8 8 9 19 13
Doubtful 4 ti S 5 iS 33
Negative 14 13 16 t8 71 S5
Group L. (Lower tone a Power of 3.)
imaaTAL S : it 1:3 4 ; f S : $ ioial ru cm
Ascending
Affirmative 9 10 j 6 30 33
Doubtful 7 8 7 S '7 "
Negative 16 14 10 31 71 SS
Descending
Affirmative S 36 3S 10 83 64
Doubtful 4 3 3 5 IS "
Negative 10 3 i 7 .11 34
According to the Lipps-Meyer formula, intervals of Group
H should end better on the higher tone, and intervals of
Group L on the lower. Consequently in Group H the finality
effect due to the 2 ratio is opposed by the rising-inflection
phenomenon, but in Group L the two forces work together.
Comparing the totals for all the intervals which according
to the law of 2 should end, i. e., the ascending intervals of
Group H and the descending intervals of Group L, we find 59
affirmative and 47 negative judgments in the first case, as
contrasted with 82 affirmative and 31 negative judgments
when the effects of the two forces are cumulative. The
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33 W. TAN DVKB BlUCBAM.
influence of the falling inflection increases the proportion of
affirmative judgments very noticeably. Preference for the
descending intervals as more definitely final does not, how-
ever, come to light in comparing the descending intervals of
Group H with the ascending intervals of Group L — intervals
which according to the Lipps-Meyer law lack finality. In both
cases the negative judgments are more than double the affirm-
ative in number, and the totals are almost exactly the same
in the two groups.
It is instructive to combine the totals for the ascending
intervals of Group H and the descending intervals of Group
L, obtaining in this manner the totals for all judgments upon
intervals which according to the formula of Lipps and Meyer
ought to be judged to end. These may be compared with the
judgments upon the same intervals played in the opposite
direction, which according to this law are characterized by
lack of finality:
End Tone k Power of 2:
Affirmative 141 55
Doubtful 37 14
N«g«tive 78 31
First Tone a Power of 2:
Affinuktive 59 33
Doubtful SS "
Negative 14J ss
517. This last summary presents strong evidence of the
operation of some such tendency as that to which the Lipps-
Meyer law refers. When 2 is the end tone, the two-tone group
is said by these observers to end in 55 per cent of the instances,
and not to end in 31 per cent, the remaining 14 per cent being
'doubtful.' When 2 is the first tone of the p^r, the propor-
tions are reversed. Only 23 per cent are judged to end, while
55 per cent are judged to be lacking in finality.
In attempting to account for the judgments which do not
conform to the law, it is to be remembered that in exactly
one half of the instances in each group the effect of the rising
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STVOrsS 111 liSLODV. S3
or falling inflection was acting in opposition to the phenomenon
under discussion. Hence a certain ambiguity and uncertainty
is sometimes inevitable. But the inadequacy of this expla-
nation to account for all of the facts becomes manifest, when
we examine afresh the separate data from which these totals
are compiled (p. 25). Why does the same observer declare at
one time that the ascending minor third, for instance, ends,
while at another time he declares with no less positiveness
that it does not end? The fact that some of the observers
were but slightly musical accounts for part of these anomalies,'
but some contradictory judgments occur in all the records
including those of the most musical observers. How can the
latter be explained?
The suggestion was made that the fork tones were so nearly
pure that the feelings of "relationship" were weak and conse-
quently the reactions produced were not normal. But the
real difficulty did not consist in any lack of feelings of "rela-
tionship" and of finality, but rather in the fact that these
feelings were apparently often misplaced. Moreover, control
tests with harmonium and piano tones rich in upper partials
failed to decrease the proportion of contradictory judgments.
§18. To gather further data another series was arranged
containing, besides the twelve of the original series, five
additional intervals: 24:25, 9:10, 27:32, 20:27 ^iid 2740.
Five quite musical observers served, including the two most
musical of those who had assisted in the previous experiment.
The procedure was varied by putting the question differently:
"Do you feel any desire to return to the first tone?"
With the attention thus directed, it is not surprising that
some of the observers reported with certain intervals that
they desired to hear the first tone ^ain, whichever way the
melodies were played, ascending or descending. Thus was
forced into notice what has been called the law of the Return,
the law that, otitcr things being equal, it is better to return to any
■ For ei&mple, when observer Bl. reported that an augmented fourth ended utii-
(actorily on the upper tone, be was asked to hum the interval upon which he had passed
judgment, and sang a perfect fourth. The same thing occurred in the case of Td,
who, however, discovered after he had sung the interval that it was not the same as the
one he had originally heard, and wanted to change his judgment upon it.
DiBiiizcdb, Google
34 W. VAN DYKB BINGBAU.
starting point whatsoever than not to return — a simple, funda-
mental principle of musical form, of art form of any kind,
indeed.
Another law to which the introspections pointed ts not so
simply formulated. It was brought to attention by three
observers who persistendy found an additional alternative in
the case of certain intervals: the melody lacked finality, there
was no desire to return, neither tone would serve as an end-
tone but some third tone was demanded. Here was a melodic
trend, definite, positive, insistent; a property of a single pair
of successive tones, but leading beyond them to something
further,'
It was plain that the facts of elementary melodic "rela-
tionship" and the law of finality of two-tone melodies did
not tell the whole story. The phenomenon of melodic trend
seemed to be of a more complex sort, even in two-tone
groups, than is implied by any statement of a tendency to
return or not to return. Even with these simple two-tone
sequences it was necessary to recognize theoperation of some
such law as the following: Two melodicaUy "related" tones
tend to establish a tonality, and the melody is judged to end
only when the final tone is one of the members of the tonic
triad — preferably the tonic itself.
This law is not asserted to be a universal law. Indeed it
is doubtless limited in its application to the experience of
those reared in a harmonic musical atmosphere. In so far
as it is found to be valid, it indicates the probability that
the phenomena of melodic trend are not primary, but are
derived from our experience of consonance.
These experiments were supplemented by briefer and less
systematic tests upon a number of observers, unpracticed in
psychological observation. The results were in general con-
firmatory, although not as strikingly uniform as those we
have already given. Mention will be made only of four of
the observers whose records are exceptional. Two of these
exhibited a persistent preference for endings that suggested
> These intro^jcctiotu complioitcd tbe recards so much Uuit it b not deemed advis-
able to reproduce them here in full.
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STVDtSS l» MELODY. 35
the minor mode. Tested upon the interval of the minor
third (5:6) — no tonality having been previously supplied —
these observers uniformly judged the ending on the lower
tone, (5), to be satisfactory, while the ascending interval
was judged to be lacking in finality. One of these observers
is a very musical Welshman, and it Is to be recalled that
much of the characteristic Welsh music is in the minor or
as they call it, the "la" mode. Tests were made upon two
Japanese young men who had recently arrived inthiscountry
and who professed to have had but little opportunity to
hear European music. Both were singers and one was a
Ijerformer upon the Japanese flute. The tests, repeated,
gave very conflicting results, and it became evident that
either the interpreter had failed to make clear to them pre-
cisely what the phenomenon was upon which they were to
pass judgment, or else their experience of melodic trends
differs essentially from ours. Unfortunately it was not
possible to carry out an extensive series of tests with these
observers.
§19. For purposes of comparison, a third set of experi-
ments was undertaken in which the tonality feeling was not
left to be contributed by the hearer, but was definitely sug-
gested to him. In the previous experiments, the utmost
pains had been taken to exclude the operation of tonality
by arranging that neither of the tones of a given group should
belong to any tonality which might have been suggested by
the immediately preceding experiment. If any tonality was
present, it had a subjective origin. We have seen that many
apparently contradictory judgments were given, as for instance
when a minor second was judged to end, now on the higher and
at another time on the lower tone, both judgments being
positive and emphatic.
In the experiments now under discussion, on the other
hand, the device was used of controlling the tonality, impos-
ing it from without and testing after the judgment had been
made to see whether or not the objectively given tonality had
been retained. To facilitate this procedure, a piano tuned
in equal temperament was used instead of the forks.
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W. VAN DFKE BISGBAM.
These experiments were carried out upon five musical
observers, practiced in psychological observation. Three
of these were quite naive as to the nature or course of the
experiment.
All the intervals of the tempered scale exclusive of the
octave were employed. Each interval was used, beginning
at every possible position in the scale: thus the ascending
fourth was heard, beginning on i, 2, 3, 5, 6 and 7 of the scale.
The series was given in double fatigue order. The experi-
menter noted down the observer's introspections regarding
the trend of the interval, or trends, for several optional
directionsof melodic movement wereoften detected. In these
instances where more than one leading presented itself to
the observer, an effort was made to determine the relative
strength of each.
The result suggested by the previous experiments came
clearly to view: so long as the given tonality was maintained,
the trend of any interval, ascending or descending, was toward
some member of the tonic chord, preferably the tonic itself.
Individual diflFerences showed themselves as stronger or
weaker demands for the tonic as the end-tone, as over gainst
the third or fifth when the latter were nearer than the tonic.
For example, in the key of c, observer Rn felt that the sequence
g' f demanded c' as its third tone, whereas the other four
observers found the trend to e' stronger. The uniform ten-
dency for all five observers, however, with all the intervals,
was to rest in one of the tones of the tonic chord.
Our contention is that in the previous experiments with
no objectively supplied tonality, the anomalous results and
contradictions above mentioned are explicable on the hypothe-
sis that tonalities, now one and now another, arose in the
mind of the observer. The minor second e"-/ would at onetime
chance to suggest the tonality of/ and end satisfactorily on
the upper of the two tones; while at another time the tonality
of c would arise, entailing quite different demands.
520. We have too long neglected to specify what is implied,
psychologically, in the term tonality. By a tonality is
meant a group of mutually related tones, organized about a
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STVBISS IN ItRLODr. 37
single tone, the tonic, as the center of relations. Sub-
jectively a tonality is a set of expectations, a group of
melodic possibilities within which the course of the successive
tones must find its way, or suffer the penalty of not meeting
these expectations or demands of the hearer and so of being
rejected as no melody. Of these different demands, that for
an end on a certain tone is the strongest and most charac-
teristic.
It is not meant to imply that this tonality, this system of relat-
ed pitches with a common center of reference, is present in
consciousness as a group of auditory im^^es. Often there is
only a single simple auditory or vocal-motor image or percept
to be detected. The tonality consists in the aUi^wfe of which
the imf^eismerelythesuperficial manifestation or sensory core.
One can image the tone of 320 d.v. as a tonic in the key of
e or as a median in the key of c, and the auditory image will
be identical in the two cases, but not the total psychosis.
There will be an entirely different organization of expectations,
an entirely different attitude, an entirely different set of
anticipations and demands, a preparedness for one set of
experiences, but not for another.
So much an impartial introspection cannot fail to disclose.
The position here advanced is thatthesesame "attitudes" are
constituted in large part of kinaesthetic elements — reports of
processes of motor adjustment.
Suggestions toward such an interpretation of the tonality
phenomenon were abundant enough from some of the ob-
servers. When Ha. felt a melodic trend unrealized, he often
described it as a vocal tension, due to a tendency to sing the
desired pitch. An. reported kinaesthetic sensations from the
throat as accompanying the feeling of expectation. He
also mentioned sensations of strain and tension in other
regions, notably the diaphragm, these general tensions being
especially prominent at the Instant when he was attempting
to retain an elusive tonality £^:ainst an auditory distraction
(as when, for instance, given the tonality of c, he was asked
to listen to the interval c-f.) Do. found that "the effort to
hold a tonality involves general organic tensions. Any lapse
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38 W. VAS DYKB BtNGBAU.
of attention or shifting of muscular tensions precipitates a
shift of tonality. Changes of breathing will do this," etc.,
etc.
Considerations such as these pointed toward the value of
an approach to the problems of the melody experience from
the side of its motor accompaniments, and resulted in the
experiments reported in Part III upon the motor effects of
simple melodic stimuli.
Whatever the nature of a tonality 'attitude,' whatever its
relations to sensations of strain and muscular movement —
it is at least a phenomenon which widely pervades the musi-
cal experience of hearers who are familiar with European
music. The question now arises whether either the tonality
experience or the experience of finality in two-tone sequences
is primary, original, fundamental: Does the law of 2 describe
a primitive, natural tendency or preference, which has oper-
ated in the course of historical development to mould our
musical system, or does it describe certain secondary,
derived phenomena which would not be discoverable in an
experience wholly uninfluenced by association? Proofs of
the former alternative the writer has been unable to discover.
Moreover, the history of our musical system points toward a
gradual evolutionary process in which the primary phenomena
of consonance have been efficacious factors. Hearers whose
minds have been influenced by association with such a musical
system, when listening to certain two-tone sequences cannot
avoid feeling a preference for one of the tones as an end-tone.
Some of these preferences lend themselves to formulation in
terms of the Lipps-Meyer law of the number 2; but this law
is only a special case of the more general law that every
melodic interval trends toward one of the tones of the tonic
chord of the tonality which it arouses. The law is based
upon the tendency of every interval, yes, of even a single
musical sound, to establish a tonality attitude. The manner
in which the law operates will be evident from one or two
simple illustrations.
What shall be said, for instance, of those curious, some-
times baffling experiences, in which a second tone is at first
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STVDIBS IN MSIODT. 39
unwelcome, and then quicldy makes itself at home and usurps
the place of what had before been anticipated as the final
tone? In certain instances nothing is more natural or
inevitable. The first tone arouses a slight tonality feeling,
making itself the tonic, so that if we call this tone c, we shall
have an 'attitude' in which any of the tones c, e, and g of the
tonic chord (but especially c itself), would be welcomed as
possessing something of the quality of finality. Suppose now
we hear the rising fourth c-J. When / first enters, as a final
tone it is not welcomed; it does not meet the requirements of
those expectations aroused by the first tone. But c-f is a
harmonious interval: it immediately tends to shift the oi^ani-
zation of the tonality feeling to something which will include
both c and / in one common tonic chord. This is, of course,
thechordZ-a-c-/, of which/is the fundamental. If this tran»-
tion is successfully made, — and the chances are that such a
transition can be avoided only with conscious effort, — then
/ becomes a final tone, and the interval which at first felt
incomplete and unsatisfactory comes to a definite close.
Why does the descending fifth end while the rising fifth
does not? When one hears a tone c and then its fifth, both
fit without readjustment into the c-e-g tonality suggested
by the first tone, and for complete finality one wishes to
hear again the tonic c. But if, instead of ascending from the
tone c, we hear a descending fifth from the samestarting point
the situation is altered. The chord which includes the
original c and this new tone F is the chord F-A-c. Our
demand is, accordingly, to hear as a final tone the tonic of
this chord, which is F. A similar treatment applies to
every instance of "direct relationship" in which the law of
2 was found to hold good. This law of the powers of 2 is
no primitive universal law: the phenomenon it describes
is peculiar to those minds habituated to a musical system
whose scale has a basis in the laws of consonance and dis-
sonance.
§21 . The overshadowing r6le played by habit or association
in the drama of our esthetic experience is not always rect^-
nized. The effect of habituation in rendering disagreeable
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40 W. VAN D7KB EINCBAU.
sequences tolerable or pleasant and in changing unrelated
into related tones, has been shown by Emerson' and also by
Meyer', although the latter finds in his results sut>stantiation
for a very different contention, namely, the universal applic-
ability of the "complete scale."
Emerson worked with extremely small melodic intervals
and found that after much experience with these small inter-
vals his observers developed preferences for certain sequences,
showing that a melody can be constructed of tones all of
which are within the compass of a semi-tone.
Meyer constructed some 'quarter-tone melodies' from the
intervals of his complete scale. At the initial performance,
the effect was judged by most of his observers to be disagree-
able, but on repetition this judgment was modified, and two
weeks later, at still another hearing, some of them came to
appreciate and enjoy the music which had before been strange
and incomprehensible. What an excellent illustration of
the law that we do not accept as melodically good that which
we cannot in some measure anticipate!
Subjected to careful introspective analysis, the feeling of
finality attaching to the second tone in the interval 3 : 4 differs
in no essential from the feeling of finality attaching to the last
tone of a purely arbitrary tone combination with which one
has grown familiar. In each instance the sense of finality con-
sists of the same kinaesthetic sensations in throat and dia-
phragm, the same feelings of relaxation, the same repose, the
same slight retardation in the rate of mental flow.
This effect of habituation is a familiar fact in the musical
experience of everyone. Tonal sequences at first bizarre,
strange, unmusical, later come to be appreciated, understood
and enjoyed. Some degree of habituation to £my succession
of intervals whatsoever makes possible the act of recognition,
of acknowledgment, of 'welcoming' the successive tones, to
use Professor Royce's apt phrase. Habituation, then, is
' L. E. EmeiBOQ, "The Feeling Value of Unmuiical Tone Intervals," Banord
Psyehotogieal Studies. iqo6, 2, itg.
*M. Meyer, "Experimental Studies in the Psychology of Music," Am. J. Pty.,
1903. 14, 4S6.
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STUDIBS IN UBU)DY. 4'
sometimes a powerful factor in making possible that active
participation which seems to be demanded of the hearer
before the succession of musical sounds can for him be unified
into the oi^ianic whole we call a melody.
S22, Summary. These studies began with a definition of
melody which laid stress upon the feeling of unity. When the
separate tones of a series are felt to be related to each other in
such a manner that each tone forms part of a coherent whole,
the succession of tones, we said, is felt to be a melody, and the
melody problem was stated to be the problem of explaining how
this feeling of melodic unity arises. An analysis of the psycho-
l(^cal elements of melodic structure revealed many and varied
sources contributing to the generation of this unity. One
group of factors, however, stood out as of unique importance,
namely those due to the relative pitch of the constituent tones;
and to the consideration of problems in pitch relationships the
scope of the present investigation was limited.
A survey of the efforts that have been made to reduce the
facts of melodic "relationship" and of melodic trend to simple
mathematical formulation was followed by an account of three
sets of experiments upon the phenomena of melodic trend in
two-tone groups. These trends, with which the feelings of
finality or of lack of finality are closely bound up, were found to
be due to (o) preference for the lower tone as such as an end
tone (phenomenon of the falling inflection), (4) preference for a
return to the first tone as an end tone, (c) preference for the
expected ending (if one knows that a given tone is to be the
last, its arrival may be sufficient to arouse the feeling of final-
ity quite apart from the operation of any other factors), and,
finally, {d) preference for an end on one of the tones of the
tonic chord — and especially the tonic itself — of the suggested
tonality.
This formulation, contrasted with the formulation in terms
of 'the law of the number 2,' has the advantage of covering
more of the observed facts' and the disadvantage, as some will
consider it, of conceding that the phenomenon described is
e numerous instances in which S ; q and 15 : 16 &re judged to end
rhich is not a poner of 1.
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41 W. VAN DYKB BINGBAM.
probably not elemental, primitive, but rather a resultant,
traceable to the laws of habit and the harmonic structure of
the music with which the observers were acquainted. Accord-
ing to this view, the laws of consonance are primary, not the
laws of melodic "relationship."
This latter view finds confirmation in the instances cited
where the feeUngs of "relationship" and of trend were clearly
the oul^owth of habituation, of repetition, of custom, of asso-
ciation, of mere expectation.
Mention was made of the high importance which seemed to
attach, in the introspections of certain of the observers, to
kinaesthetic factors present in their experiences of tonality,
"relationship" and trend. These facts, togetherwith the fact
that the phenomena of "relationship" are exhibited by pairs
of tones which vary so widely from the simple ratios, suggest
that it is not the sensory but the motor phase of the circuit
which contributes the unity, — that it is not the relatively eco-
nomtcalactivityof the sensory nerves, but the relatively unified
response of the motor mechanism which gives rise to the feeling
of "relationship."
Our problem, then, shapes itself as the task of studying the
motor responses which melodic stimuli elicit, to discover
whether here is to be found any further clue to the explanation
of melodic unity.
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EFFECTS OP MELODIC STIMULI UPON MUSCULAR MOVEMENT
§23 To gather definite data regarding the relation of
movement to the melody experience, the following experi-
ments were undertaken, designed to test the effects of simple
melodic stimuli upon on-going motor processes, voluntary and
involuntary.
The voluntary process studied was the tapping movement
of the index finger of the right hand. This movement was
chosen because of its simplicity and naturalness, and because
after a little practice it tends toward automatism, leaving the
attention free to be focussed upon thestimulus. Such devices
as the Jastrow automatograph and the Delabarre muscle-
recorder were rejected in favor of the means here described,
because it seemed highly probable that changes in innerva-
tion would become most readily manifest as alterations of a
motor process already going forward. Other factors remain-
ing constant, it is to be expected that a neural current will
tend, at least in part, to find its way out of the central system
along that motor channel which is already in use. Moreover
the investigations of Stetson' and others upon complex or
"combined" rhythms have made it certain that a concurrent
movement coming into coordination will affect an accom-
panying uniform movement.
The form of apparatus used is an adaptation of the simple
device employed by Stetson for recording rhythmical move-
ments. The hand and forearm rested naturally upon the
arm-rest leaving the index finger free to move throughout
its entire range of flexion and extension without contact.
(See accompanying figure). This free, unrestricted move-
ment was chosen because it was found that when the finger
taps against a hard suriace the contact sensations serve as a
>R.H.Stet«>a:"A Motor Tbony of Rbythmud Discrete Succodon." Ptyek.
JtM. 1905, 13, 150.
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44 V. VAN or KB BINGBAM.
sensory control which regulates and steadies the movement.
As our purpose was to detect any slight variations which
the melodic stimuli might produce in this motor process, it
was obviously better to avoid as many of these controls as
possible.
The periodic movement of the finger was recorded in all
its details as far as changes in rate, form, and amplitude
of movement in a vertical direction are concerned, by means
of the recording device above mentioned. From the leather
finger-cot a silk thread ran over a tiny pulley and through
FlODXK No. I
glass guides which prevented any loose motion. This thread
led to a rubber thread, in the middle of which was an alumi-
num writing point, which traced a record of the finger move-
ment upon the belt of smoked paper. A slight torsion of
the rubber served to keep the writing point against the sur-
face of the kymographic belt. By varying the length of the
rubber on either side of the writing point the relative ampli-
tude of the curve could be made as small as desired. Most
of the records, however, were taken with a!l of the rubber
upon one side of the writing point so that the curve was
equal not only tn form but also in amplitude to the vertical
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STVDISS IS UELQDt. 45
component of the finger movement. The tension of this
delicate rubber was so slight that it was barely perceptible
to the observer, and did not interfere with the freedom and
naturalness of the movement. Indeed, the superiority of
this recording device over that of a tambour lever lies in the
perfect freedom of lateral motion allowed; because there is
no restraint upon the finger movement, there are no sensory
controls other than those cutaneous and kinesthetic sensa-
tions due to the movement itself.
The belt of smoked paper ran between two cylinders placed
about two meters apart. It was driven by an alternating
current, constant-speed motor whose only variations were due
to fluctuations in the rate of the generator of the Cambridge
lighting plant. Tests with vibrating forks of 50 d. v. and
500 d. v. showed that the maximum variations in the rate
of the belt of smoked paper were less than one and one-half per
cent. As a precautionary measure, however, a time line
was made a feature of all the records, interruptions at periods
of one second being furnished by means of a Lough self-
actuating fwndulum, placed in a distant room.' Precaution
was taken to banish all sound which might arise from the
recording apparatus, such as the ticking of the electric
markers. The driving mechanism was placed outside of the
experimenting room, as otherwise a low hum from the motor
could be heard even when it was encased in a "sound-proof"
box.
Oneelectric marker, as has been said, furnished the time line.
This line also served as base line for measuring amplitudes.
Another marker was in circuit with the keyboard of the har-
monium which was used for giving the melodic stimuli, and
furnished the record of the course of the experiment.* A
silent pendulum was used to aid the experimenter in con-
trolling the length of the sounds. The smoked record was
' Only altenuU Ups o( the tiine-muker, i. e,, one every two seconds, are visible
in the sample records reproduced on p. 51.
* It is the opinion of the experimenter that a simple pneumatic attachment to the
keyboard of an organ or piano with tambour recorder would on the whole prove more
Mtisfactory than an electrical attoduwnL
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46 IT. YAK DYKE BIKGHAM.
made F>ermanent by being sprayed with a ten per cent solu-
tion of gum sandarac in alcoho].'
Pneumographs of the Sumner pattern were employed to
record the abdominal and thoracic breathing. The degree
of sensitivity of pneumographs and tambours is shown by the
clearness with which the pulse-beat appears on the pneumo-
graphic tracings, quite plainly enough indeed, especially on the
curve of the abdominal breathing, to permit the computation
of the pulse rate if desired.
Nothing of significance for the present investigation ap-
peared, however, in these pneumographic curves. The reason
doubtless is found not in the fact that melodic stimuli do
not produce important modifications in the breathing, but
rather in the fact that the duration of the stimulus used was
too brief to permit the characteristic alterations to appear.
In this respect the conditions were quite the reverse of those in
the experiments of Foster and Gamble.' These experimenters
using musical selections of various kinds as stimuli found that
listening always tends to shorten the expiratory pause and to
make the breathing faster and shallower, but not steadier; but
no remarkable differences were found in the effects of loud and
soft or major and minor music. One is not surprised to learn
that characteristic breathing phenomena could not be isolated
when use was made of such highly complex stimuli as actual
musical selections.
524 When the subject had taken his place and the pneu-
mt^raphs and finger apparatus had been adjusted, the nature
of the particular experiment to be performed was explained.
The number of tones which were to be used was told, but
nothing further was said regarding the nature of the melodic
intervals. The subject then closed his eyes and the experi-
menter started the kymograph, so that a brief record of the
breathing was obtained before the finger movement began.
' The double-glazed p^xr uaed was too thick to be fixed by the usual device of
painting on the wrong dde. The use of a spray proved to be convenient and eiq>edi-
tjous. A"fixativespray/' to beiiadfor ten centsatanyart store, when fitted to afoot-
power bellows, proves veiy satisfactory.
'Eugenia Foster and E. A. McC. Gamble: "The Effect of Music on Tboradc
Breathing. " Amtr. Jour. Psyck., 1906. 17, 406.
Digilizcd by Google
STVDIBS IS UELODY. 47
At a word from the experimenter the subject began the tap-
ping movement taking whatever rate was most natural to
him. After the tapping had continued for twelve seconds or
longer the melodic stimulus was given. The tones were
played upon a reed organ the mechanism of which was in
electrical connection with a marker which recorded the instant
of depressing and raising the keys. The general plan was for
the experimenter to sound each tone for a period of three
seconds. It may be thought that this period was unneces-
sarily long, but the observers did not find it objectionable
and it has two very obvious advantages. In the first place
a period as long as three seconds is sufficient to permit any
motor changes which the stimulus may produce to become
evident in the record of the finger movement. And in the
second place the use of the three-second period minimized,
if it did not indeed entirely rule out, the factor of rhythm.
Stimuli whose rate is as slow as one in three seconds do not
tend to become rhythmlzed.
After the melodic stimulus the tapping was continued for
ten seconds or longer. The observer was then called upon to
give his introspection. Aside from a general introspective
record of the course of the experiment, the naturalness of
the tapping, effect of external disturbances, and the like, the
points toward which inquiry was especially directed were
two: first, does this melody end? Has it the characteristic
of finality, or is it unfinished? Does it leave you in suspense?
Does it demand something further? Secondly, the question
was raised as to whether or not the melody was pleasing. In
many cases but not in all, these two aspects, the affective and
the aspect of completeness, seemed to be felt as identical ; that
is to' say, a melody was judged to be agreeable because it
came to a good ending, or tx> be unsatisfactory because
incomplete. Not infrequently, however, one met with intro-
spective rep>orts like the following: "That is good; I like that
but it is not finished," or, " That isn't particularly pleasant,
but it ends very emphatically."
A word ought to be said about the way in which the observers
were first brought to an understanding of the phenomenon
Digilizcd by Google
48 W. VAU DTKB BlUGBAM.
which was under investigation. They were not told what
the phenomenon was, and then asked if they could observe it.
On the contrary, the plan employed was to play an inter-
val of an ascending fifth and then to play the same interval
descending and then ask for a full introspective account.
Some observers would quickly detect the feeling of
relaxation, of repose, of completeness which accompanied the
perceptiom of the descending fifth and which was lacking
when the ascending fifth was heard. Lest they should
immediately form the opinion that this characteristic of
finality always accompanied a descending interval, the per-
fect fourth was next played. This interval they soon dis-
covered makes a better ending upon the upper tone than upon
the lower. Only after the observers had become thoroughly
familiar with the phenomenon were they asked to serve as
reagents in the main experiments. With two of the obser-
vers not a little persistence tc^ther with many repetitions
of the intervals was required before they discovered the
phenomenon, but in every case it was a genuine discovery
of their own, and was not suggested to them.
§25 The observers were research students or instructors
in the Harvard Psycholc^cal Laboratory, with the excep-
tion of Po., who had, however, had training as an observer
elsewhere. All with the exception of Da. and Pu. were men.
It will be convenient to divide the observers into three
groups according to musical ability. This classification is
based upon tests in recognition and vocal reproduction of
melodic intervals, immediate memory for intervals and for
short melodies, and recognition of the fundamental note of a
chord.' The method employed in this last test was as fol-
lows: a three-clang chord was played, and after it a single
low clang, with the question, "Is this the fundamental basic
tone of this chord? Does it, in a way, represent the whole
chord? If you had to supply a bass to this chord, is this
the tone you would use?" Twenty four chords were given,
eight in the first position, and eight each in the first and
*Tlie writer scknonledges indebtedness to Profeaor Meyer for the niggntioo of
this tat of music&l abibty.
Digilizcd by Google
STUDIES III MELODY. 49
second inversions. The low tone which followed was always
a lower octave of one of the tones of the chord, and in one
half of the instances it was the fundamental. The number
of right judgments for each observer is given in the second
column of the accompanying Table 3. The percentages in
TABLE NO. s
T»h of muwa Mlily.
«o«mo.o,.™«™x^o,c™»
™e„..,.»^„™,»™»»„
1
1
1
\
J
1
1
1
i
Po
Rk
R«
D*
Ho
Ft
Ta
Me
Pu
34
10
so
16
a
4
0
100
t&
88
7S
5»
S»
a4
17
18
;:
4
-
97
9a
97
7S
77
SO
S*
the last column represent the success of the subjects in hum-
ming the fundamental tone after hearing the chord, the
series of chords used being similar to the one employed in
the previous test. Errors were most frequently made when
the low note was not the fundamental, but was a lower
octave of the highest note in the chord. It was found after
the series was ended that fewer errors of this kind are made
if the observer is instructed not to give his judgment immedi-
ately, but first to im^;e the three tonesof thechord separately,
choose the fundamental, and then make the comparison with
the low tone. On repetition of the test, this precaution
served to eliminate all errors from the judgments of Rk.,
Ho., and Da., but did not operate so successfully with those
observers whose auditory im^^nation is less facile.
The results of these tests when combined with the other
Digilizcd by Google
S« W. VAN DTKB BIKGBAM.
observations on musical ability and with the results of an
inquiry into the observers' musical interests, their eariy
training and later musical experience, made it evident that
the first three observers on the list had a fair orderof musical
capacity, although Po. was the only one whose abilities had
been much developed by training. The last three observers
form a distinct group, since they all fall much below the
others in the tests reported in Table 3, and also in accuracy
of recognition and reproduction of melodic intervals. Pu.
could not even be induced to attempt vocal reproduction.
The remaining three observers form an intermediate group.
None of the nine were entirely lacking in musical interest,
although the range represented was a very wide one.
An accurate test of ability in pitch discrimination was
not carried through to completion because it became evident
that accuracy in the discrimination of small differences of
pitch is no indication of musical ability. Po. and Rg. did
not serve during the preliminary exiieriments. Da. and Mc.
did not serve during the second half year, and their records
are included only in the first of the tables presented here.
Each observer served for a period of three quarters of an hour
once a week.
The observers it will be recalled were directed to take
whatever rate of finger movement seemed most natural to
them. The individual differences, and also the individual
variations from time to time, proved to be extremely wide.
Early in the practice experiments, the tapping of Rk., Da.,
Ta., and Mc. was much slower than it became later on, and
nearly all of the observers showed some tendency to increase
the natural rate with practice. Within a series of experi-
ments at a single ^tting, R^., Rk., and Mc. were apt to
choose a much more rapid rate for the later experiments,
unless they happened to select an unusually rapid rate to
begin with. This they were apt to do if they had been walk-
ing rapidly or otherwise exercising shortly before, or if they
had been under any slight excitement.
Not only do the records show great individual differences
in the rate of finger movement, but also in the amplitude and
Digilizcd by Google
DiBiiizcdb, Google
$3 W. VAN DrKB BISGBAM,
the general form. Ta.'s record is characteristically slow,
wide, and extremely regular. The back stroke is similar to
the beat stroke In every respect, and the transitions from the
ballistic part of the movement to the controlled portion are
smooth and even. The tapping of Da. and Mc. is also slow
and wide, but very different from that of Ta. because the
ballistic strokes are made with a jerky movement, and the
portions of the curve between the ballistic strokes are very
irregular. The muscular coordination is much less accurate.
Ho. and Pu. also use a characteristically slow rate, but the
amplitude of movement is small. One finds very consider-
able variations in amplitude in the records of both these
observers. There is also an irregularity of line due to the
fact that the ballistic portion of the movement seems to be
almost wholly lacking, even from the beat strokes, (*. e., the
finger seems to be almost continuously under control of
extensor and flexor muscle sets combined.) The maximum
velocity of the beat stroke is much less with these observers
than with any of the others. Rk. and Rg. are the two who
show the widest variations of natural rate from time to time
and also the greatest changes in the form of the finger move-
ment. Both of them use a medium amplitude, but this ampli-
tude varies widely. On the whole, their records show that a
much greater prominence is given to the ballistic phase in
both beat stroke and back stroke. In Po.'a records, which
exhibit the most rapid rates of any of the observers, there
is very littie in the curve other than the ballistic phase: there
is almost no pause between strokes. In the records of Fr.,
on the other hand, there is always between the vigorous
ballistic strokes a relatively long relaxation phase during
which the movement is extremely irregular: during these
periods the finger seems to be not under the control of either
the extensors or the flexors.
With reference to the amplitude of finger movement, it
may be noted that with the exception of Ta., those who used
a wide amplitude were those who had had some practice at
the piano.
Digilizcd by Google
STUDIES IN MELODY.
TABLE NO. 4
Normal record of rate of^ger mmcmeiU, and fatigue record. Rale of lapping during sue-
eetsiae periods of Mru tecondt each. Read from left to right. The sioieest rates are
printed in boldfaced type. Faslext rata in iiaiia.
\
..^^
,.„o„»o„
Po
3^2
»S6
a.^fi
m
aS4
Stt
aSi
160
«5J
i1
}
ass
"39
»3S
R«
107
104
106
«
w
9S
100
99
lOb
IQ4
toS
Rk ,.,
130
'33
133
130
"33
•3*
131
lae
130
124
114
Ul
U.
m
1 01
WS
WS
100
»,1
»s
104
99
97
98
Ho ...
96
9.1
90
fl>
00
1)1
91
M
8»
88
88
88
Fr
aog
aoS
»»
m8
J07
310
>«>
»i7
314
331
314
Ta ....
7*
78
TO
77
78
80
7<J
79
St
77
77
78
Mc. . . .
84
as
83
86
87
tt
JS
8S
86
93
9>
</>
Pu
III
in
104
107
104
104
109
no
i/J
hi
iiS
"S
S26 In the accompanying Table 4 are given the measure-
ments of a set of records taken without distraction or stimulus
of any kind, for purposes of comparison with records in
which melodic stimuli were used. Elach number gives the
rate of 5nger movement during a period of three seconds.
The rate is expressed in beats per minute, which is the same
as the method employed in music for designating rates. The
numbers, then, represent the metronome rates at which the
observer was tapping during succesave periods of three
seconds each. To facilitate the reading of the table, the
rate of the period of slowest tapping within the record of
each observer is printed in bold-faced type, and the fastest
rate is printed in italics. A glance at the table will show the
extremes between which the rate of tapping varied within the
course of the period of twenty-seven seconds covered by the
record. It will be seen that four of the nine observifts
exhibit a tendency toward an increase in rate during this
time, while an opposite tendency appears in the records of
two observers.
The question naturally arises whether the factor of fatigue
may not enter in to modify the nature of the tapping move-
ment as the experiment proceeds. This does not seem to be
the case when an experiment does not continue for more
Digilizcd by Google
54 IT. VAS DYKE BINGBAU.
than thirty seconds, as was the case with nearly all of those
to be described below. For purposes of comparison, how-
ever, there is given in connection with the normal record of
the accompanying table what may be called a fatigue record.
This is really a continuation of the normal records, one
minute of unrecorded tapping having been permitted to elapse
between the close of the normal record and the beginningof the
fatigue record. During this interval the rate of tapping of
four of the observers showed a diminution. With four of the
others an increase in rate is seen. The record of Fr. showed
the greatest variability and irregularity during this closing
period. Only two observers, Da. and Mc, reported any
feeling of fat^e after this experiment.
Fatigue maJces its appearance very quickly if a rate more
rapid dian the natural rate of tapping is employed. When
the recent taps as rapidly as possible the entrance of fatigue
brings with it a slowing of the rate and an increase in irregu-
larity of rate and of amplitude.
§27 Tables 5 and 6 exhibit the effect of auditory stimuli
upon the rate of tapping. These tables are prepared in a
manner similar to the table of normal tapping; each number
represents the rate of tapping during a three-second period.
Measurements of the first few taps of each record were not
made because they are certain to be more or less irregular.
Measurements of the rate of tappii^ are given for three periods
of three seconds each before the incoming of the stimulus.
The stimulus consisted of the tone a sounded for six seconds
on the harmonium. Then after an interval of three seconds, '
this tone was sounded again, this time for only three secxtnds,
but it was immediately repeated and sustained for three
seconds longer.
A study of this table should disclose the effects which are
produced upon the rate of tapping by a musical sound and also
by the repetition of a musical sound. It will be noticed that
in the records of four of the seven observers there is a marked
diminution of rate following the entrance of the first stimulus.
The record of one observer shows a marked increase of rate
at this point. In all cases there appears to be a tendency
Digilizcd by Google
STUDIES IN MBlOOr.
TABLE Na I
Bffeaofaan^tont,aiidoflkaiUn£Tepeated.onr(>teoffimttr-m<wmaii. The rale durint
tack thrte-steoud ptriod of tMe exptriment is then. Stadfromleft lo rifkl. Niamberi
skmnnt dtereatt in ratt at eritictil points in the record art prinltd in bold face typt;
ale art printed in italics.
,
' 1 '
■c)
■
Rk
.*
140
141
>»
130
13s
«3J '35
13s
158
IH
.0.
109
104
82
96
So
78 78
(97)*
90
Ho
79
81
So
79
78
76
7S
7*
71
60
Fr
..«
IS7
'S7
166
15s
US
UO
iSi
ISO
iss
He
■ 16
118
iiS
"S
118
III
"7
iig
130
T>
77
77
76
69
75
77
76
76
80
Pu
60
63
69
66
es
65
66
67
7'
ja
« fori.] Ma wbs
uMoppad; uul UtMi b«t>D XnMof V7.
Effect of sudden noise on rale of finger-motetnenl. Entrance of stinmlus at beginmnfof
fifth Ihree-stcond period of Ike record.
60
I
116
114
IS3
160
"9
"4
194
194
69
70
197
to return to the original rate while the tone is still sounding.
The records of three observers show another diminution in
rate immediately following the cessation of the stimulus, but
no decided change occurs in the other four records at this
point. With the entrance of the stimulus the second time a
retardation occurs in three records, but this time it is not
nearly as large as in the first instance. The repetition of this
stimulus is accompanied by an increase in the rate of one
observer and a decrease in the rate of another, the rates of
the other five observers not changing materially at this point
in the records. The cessation of the stimulus, however, is
accompanied by an increase in the rate with two observers,
and a decrease in a single instance. One observer stopped
tapping entirely for a brief time when the stimulus stopped
and then began again at a rapid rate.
Digilizcd by Google
56 W, VAN DYKB BIHGBAM.
It thus becomes evident that under the conditions of this
experiment the entrance of an auditory stimulus introduces
a disturbance in the process of tapping which shows itself as
a change in rate, usually of the nature of a retardation.
The nature of the disturbance to the tapping is made very
evident by direct inspection of the kymographic records.
The next tap after the one during which the stimulus enters
is frequently the slowest and also has the greatest amplitude
of excursion of any tap on the record. The entrance of the
stimulus a second time, after a pause, produces similar but
much less marked effects; and when no time interval elapses
between the clang stimulus and its repetition no effect what-
ever is apparent.
The effects of a momentary noise as a distraction are illus-
trated in the experiments summarized in Table 6. Here,
too, a marked change of rate appears in nearly every instance.
The solitary exception is Rk., and a closer examination of his
record than the table permits shows clearly that here too the
the stimulus had its effect. The tap immediately following
the one in which the stimulus entered is the slowest tap of
the record, but in this instance it is followed immediately by
taps of a more rapid rate which bring the rate for the entire
three seconds up to the figure given.
It seems to be a general tendency, then, for alterations in the
natural tapping rate of the finger to occur upon the entrance
into consciousness of an auditory sensation. This very
natural phenomenon does not call for an elaborate explana-
tion. It may be dismissed by referring it to that large group
of experiences which have as their most prominent feature the
characteristic of "shock," of sudden disturbance of equi-
librium demanding an adjusting act of attention, and which
consequently interfere more or less with pre-existing adjust-
ments and on-going activities. Stated in strictiy neural
terms, the phenomenon is reducible to an instance of the
general law of diffusion, the auditory stimulus introducing
a shift of neural tensions throughout the cortex, and more
particularly affecting those localities in the Rolandic region
which are active at the time.
Digilizcd by Google
STUDIES in ItELODr. SI
The modification of rate shows itself most frequently as a
retardation probably because new activities of adjustment
result in inhibition of the finger movement through drain^^
of the neural energies elsewhere. To explain those relatively
infrequent instances (15 per cent of the total number) where
acceleration follows the entrance of the auditory stimulus,
one might assume that the stimulus operates to produce a
greater alertness, or heightened general activity in which the
tapping movement shares. To explain why the very first tap
following the onset of the stimulus is sometimes unusually
wide and of long duration, but occasionally the reverse,
recourse may be had to the facts brought out by Hofbauer*
and Cleghom* that an auditory stimulus occurring at the
beginning of the contraction phase of a movement augments
the movementand this reinforcement makes the total duration
of the contraction-relaxation process greater; but if the
stimulus enters at the banning of the relaxation phase of the
cycle, the process of relaxation is hastened and the total period
is diminished.
§28 We may now turn to the experiments in which melo-
dic stimuli were employed, asking what significant changes of
rate appear, to what extent these variations are the same for
the different observers under identical conditions, and especi-
ally, what relations exist between changes of rate and the
typical phenomena of melody. Do characteristic changes
accompany the perception of a melodic interval which is felt
to lack finality? How do these changesdiffer from those pro-
duced by an interval which "ends?" Does a succession of
two tones which lack melodic "relationship" have a peculiar
effect? Whatof the "return?" What of disappointed expec-
tation? What of the passage to a tone which necessitates a
shift of tonality?
Tables 7 and 8 show the changes in rate of tapping which
accompany the hearing of the melodic interval of the fourth,
i.e., of two tones whose vibration rates are in the ratio 34.
> L. Hofbauer, Areh.f. d. (ei. Phyiiol. (Pfltlger's) 1897, 63, 546.
■Alleo Cleghoni, "Tlie Rdafarcement of Voluntary Musculu Conbactioa."
Am. Jour. Pkysicl. 1898, /, 338.
,v Google
58 W. VAN DYKE BINCBAU.
This is one of the most interesting of any of the melodic inter-
vals from a psychological point of view because of the strong
sense of finality which it gives when the higher tone is the last.
When heard as a descending interval, it lacks this finality, and
yet does not leave one wholly in suspense, for it has those ele-
ments of finality which are the property of any descending
interval as such, and also those which belong to every tone in
the tonic chord. Because of this complexity, judgments
regarding the finality of the descending fourth are often uncer-
tain and variable. As an ascending interval, however, there
is seldom any doubt in the mind of the observer that the group
is a completed whole, emphatically coming to an end. It is
indeed the only ascending interval of which so broad and posi-
tive an assertion can be made. The minor second and minor
sixth are the only other intervals at all comparable with it in
these respects.
The tables are made up, as were the previous ones, of num-
bers representing the metronome rate of the tapping move-
ment during successive periods each three seconds in length.
The two tones were each sounded for three seconds, and the
numbers immediately under the letters which represent the
tones consequently express the rate of tapping during the
course of the melodic stimulus. To call attention to changes
of rate at critical points in the course of the record, use is made
of bold faced type where retardations occur, while accelera-
tions are indicated by italics. In deciding whether or not a
change of rate accompanying the entrance of a stimulus was
sufhcient in amount to be of any significance, the writer has
taken into account the degree of regularity shown In the tap-
ping of the six seconds preceding, but has neglected the pieriod
before that, which was often so near the beginning of the tap-
ping record that the reagent had not as yet found his pace.
Examining Table 7 with reference to the distribution of
retardations and accelerations during and immediately follow-
ing the melodic stimulus, one notices at once that the retarda-
tions all occur during the sounding of the tones (six during
the first tone and two during the second) whereas all the accel-
erations are found within the period of the last tone and the
Digilizcd by Google
STUDIES tit MEWDT. 59
period immediately after it (two during, and six after, the last
tone).
In contrast with this table of the ascending fourth, the table
of the descending fourth exhibits much less uniformity in the
distribution of accelerations and retardations. The most
striking feature is the large proportion of retardations which
occur during or immediately after the sounding of the second
tone.
eriiKol poini,.
<! r
Po .
»07
94
los
190
76
iiS
loS
95
106
103
192
75
117
94
104
103
186
86
i»
91
103
93
180
73
US
91
99
93
173
7»
118
MS
lOI
'85
87
M3
96
96
179
78
93
90
•ft
•Stopi»l twine
TABLE NO. 8
PaStd Fourth, Deicaidini.
f ('
148
91
104
95
81
93
97
it4
3S8
95
98
99
»I9
85
3U
96
">}
99
ai3
80
loS
»58
97
103
103
SIO
74
Utt
390
96
un
104
3X8
73
116
9S
«3
77
114
as8
Rg.
103
Ho
116
529 The significance of these facts appears when they are
brought into comparison with the results of the previous group
of experiments. There it was found that a repetition of a mus-
ical sound following shortly after the cessation of the original
stimulus produces effects similar to those of the first sound,
but much less marked. And when one musical sound is imme-
diately followed by another which does not differ from it in
Digilizcd by Google
«0 W. VAN DrSE BINGBAM.
pitch or intensity there is no apparent effect upon the on-going
activity, the only changes observable being in the direction of
a return to the natural rate.
When successive tonal stimuli differing in pitch are used —
in this instance two tones at an interval of a fourth — the char-
acteristic variations of rate, most of them retardations, follow
the entrance of the first tone; but when this is succeeded by
the second tone, one does not find the same absence of further
variations which marked the appearance of a second tone iden-
tical in pitch with the first. Instead one finds fresh changes of
rate; and upon comparing the ascending fourth with the des-
cending fourth one is impressed with the fact that the accelera-
tions belong mainly to the rising interval, while most of the
new retardations accompany the hearing of the descending
fourth. This, it will be bom in mind, is an interval that "ends"
better on the higher tone.
An hypothesis with reference to the significance of these
motor phenomena may here be briefly outitned, as follows:
(a) Attention is an activity which involves both special and
general motor adjustments. (6) The general aspects of
attentive activity are of such a nature as to affect general
bodily conditions; and, specifically, (c) the rate of a circular
motor process (such as the finger-movement) which is going
forward semi-automatically, will be affected by these activi-
ties, a decrease in rate signifying inhibition, due to increased
activity elsewhere, and an acceleration signifying that the
task of attention in oi^anizing these activities is being suc-
cessfully carried out. Retardation or inhibition, it is to be ex-
pected, will enter with the appearance of the stimulus demand-
ing attention. Continued slow rate of movement will result if
the organizing activities of the attentive process continue to
meet with difficulties, while the rate will be augmented as the
new adjustments come to be efiicientiy established.
In terms of this hypothesis, the above facts with reference
to the hearing of the rising fourth would be described as fol-
lows: Sudden rise in the level of attention at entrance of stim-
ulus, continued attentive activity during the sounding of the
tones, and finally, subsidence of attentive activity with the
Digilizcd by Google
STODIRS lit UELODF. 6 1
satisfactory completion of its task; or, stated differently, pre-
sentation of a problem of adjustment as stimulus enters, con-
tinuance of the process of establishing coordination during the
sounding of tones, and then increase of rate signifying the effi-
cient accomplishment of this act.
It is this acceleration accompanying the sense of finality
which seems to be of particular significance.
S30 In testing the hypothesis, the introspections of the
observers must be taken into consideration, for not always is a
melodic interval heard in the same way. What an interval is
to the observer depends as much upon the "attitude" with
which it is received as it does upon the ratios of the physical
vibration rates.'
The order of arrangement of the observers in all the tables,
it will be recalled, is that determined by the tests of musical
ability. Po., the most musical, reported that the ascending
fourth, while it has the attribute of finality, is less final than
some, e.g., the descending fifth.
"The pitch of the second tone came as a surprise. The feeling of
satisfaction came only toward the end of the second sound, after I had
got it placed with reference to the firat. The instant of entrance of the
sense of satisfaction was very marked."
(The rate for the first four taps of this period was 210, for the
next four it was 228 and for the remaining three, 232.) This ex-
perience might be described as the final acceptance of a second
tone as a tonic which when first heard was not so construed.
If, during the hearing of the first tone, a tonality feeling gets
established with this tone as a tonic — as is very frequently the
case — the transition to a tone of different pitch presents three
possibilities, (fl) It may be an "unrelated" tone, foreign not
only to the tonality already in mind but also to any other tonal-
ity withinwhich the first tone would find a place. In such an
instance there can be no melody feeling,' for there is no coher-
ence or relevance between the tones; they do not tend to insti-
'C/.«t^a,p. ja/.
' Here, and througbout the discussion o( the experiments, it will be understood
that these statements are made soldy with reference to the experience of observers
who are (amiliar with a harmanic muacal system.
Digilizcd by Google
6» W. ¥AS DYKB BIHCBAM.
tute a common set of expectations; they do not belong to the
same whole. (A) The second of the two tones may be "related"
to the first as to a tonic. It belongs to the tonality already in
mind, and consequently it is welcomed, as partially satisfying
the expectations of the hearer; but it does not wholly satisfy
them. Instead, it only makes more definite and insistent the
demand that the first tone shall be heard again, at the end of the
melody; it intensifies the original tonality feeling. If the se-
quence of tones ends here, one experiences the feeling of unrest
and dissatisfaction which accompanies disappointed expecta-
tion or thwarted intent, (c) The second tone may be capable
of entering into tonality relations with the first, but not into the
tonality of which that tone is the tonic. This necessitates a
shiftoftonality. In place of the organized set of expectations
already present, a different set appears. The octreme instance
of this peculiarly subtile and elusive process occurs when the
second tone becomes itself the tonic of a new tonality, usurping
the power and function originally held by its predecessor, and
organizing a new set of expectations. Such an instance is
found in the interval of the ascending fourth.
Po. was probably not the only observer who experienced this
peculiar shift of tonality upon hearing the interval of the
ascending fourth ; but he is the only one who detected and de-
scribed the feeling of transition and the satisfaction which fol-
lowed. Rg. reported that the interval seemed to him to be
rather indifferent, but after hearing /c' he said that c'f had
more finality about it than he had thought at first. Rk.
reports, "That sounds like 'soldo'; there is no need of a third
tone." Ho. "Thatends! It is very agreeable." Fr. "That's
all right." Ta. found it difficult to give an introspective
report. The interval he said was elusive, and it was hard to
say just what the effect was. Pu. reported no definite effect
of any sort. It must be noted that even in the case of these
last two observers an acceleration of rate occurred immediately
after the close of the tone.
With the descending fourth we find much less uniformity in
the distribution of accelerations and retardations, and also a
greater diveraty in the introspective reports. The most
Digilizcd by Google
STUDIES IN MELODY. 6 j
striking and important feature is the large proportion of retar-
dations which occur during or immediately after the sounding
of the second tone. Po. reports that the interval was pleas-
ing, but not wholly satisfactory because it lacked finality.
During the sounding of the second tone his rate recovered
from the slowing-up produced by the first tone but after the
melody ended there was a retardation. For R^. the interval
lacked finality but as to agreeableness it was indifferent.
Rk.'s introspections were interesting. "That is all right, but
I can't help thinking in three's." That is to say, he gave an
intellectual judgment that the interval was complete but
really felt a need for something further. (Note the retardation
in rate.) Ho.says, " I should like to add a third note but it is
not bad." Fr., "Unfinished, but pleasant as far as it goes."
Ta. "I cannot decide. I keep changing my mind. It is a
puzzling interval." Pu., "Very definitely complete and
pleasant."
If one examines the table in the light of these introspective
comments, it is found that five of the seven records suppwrt
our hypothesis with reference to the motor eflect of the finality
experience.
With all of the remaining tables the introspections are pre-
sented in very brief summary. The observer's own words are
used, as far as the necessities of condensation allow.
§31 Tables 9 and 10 should be examined tt^ther. They
show the effects produced by the melodic interval of the per-
fect fifth, ascending and descending. With regard to the
aspect of finality, all the observers with the exception of the
two least musical ones are agreed that the ascending fifth is
lacking in completeness. In spite of this fact, the proportion
of retardations and accelerations during the period while the
second tone was sounding and immediately after, do not show
a balance in favor of the retardations. The lack of finality in
this interval is not sufficientiy marked to produce the vivid
experiences of tension which characterize the perception of
some melodic intervals. A more significant reason why one
should not expect a larger proportion of retardations here, will
become evident shortiy.
Digilizcd by Google
W. VAN DYKE BINCBAM.
TABLE NO. >
Perfed Fifth, Auttidint- Rait of tafping during ._.
Rtadfnm kfl U> rigU. Nrnnberi thawing decrtate
art printed in bald fact type. Increosti in rait or
ptritds «} three stcondt each.
rate at eritical points in the record
»2S
314
12S
114
338
336
iig
130
IJ7
irf
laS
133
>»7
117
iiS
119
U6
M
"S
*34
»33
13s
'J7
m.
»3J
73
74
76
71
77
80
10*
109
loS
lOB
III
IM
fnlrotpeclions.
Po, A Knse of finality, but not completely final. Pleasant.
Rg. A beginning, not an end. Wanted to go 00.
Rk. Want to hear first again.
Ho. Needs third tone. Not extremely bad.
Fr. Unfinished. Pleasant.
Ta. llat is finisbedl Felt so the instant it sounded.
Pu. Faiiiy complete. Agreeable ending, but I do not like so wide an interval.
TABLE NO. 10
Perfea F^lh, deicending.
l"
c-
Po
•97
..,
106
109
78
103
S04
"5
toS
113
335
78
106
*oS
I3S
108
78
"3
9H
13a
lOS
un
78
un
308
Ui
106
78
97
"4
10$
lop
110
S3
319
133
103
104
R«
143
105
aig
Ta
*Btappad Tapplnc
Introsptetioni.
Po. No suggestion of further movement. Satisfactory.
Rg. Left no impression.
Rk. Doesn't need a third. Pleasant.
Ho. Can't say as to finality. Faidy agreeable.
Fr. Incoherent Unfinished. Unpleasant.
Ta. (Introspection uncertain,)
Pu. Did iK>t demand third note.
Digilizcd by Google
STUDIES III MSLODT. 6$
Table lo, the descending fifth, presents a much more uni-
form appearance. Accelerations following the close of the
melody occur in every record except that of Fr., which shows
no change in rate at this point. The introspections, however,
are not as definite, three observers failing to report anything
positive regarding the finished, self-complete character of the
melody. The only one, however, who found the melody
incomplete was Fr., the observer whose rate is the only one to
show no increase at this point.
TABLE NO. II
Ptrftcl Fifth, ittetitdiit[. TkrM Uma txftckd. Aterate rait tf tappmf hy Ihrtc-tecond
periods. Read from l^t U rifU.
po
>84
io8
104
184
117
108
375
m6
117
77
to8
a77
US
«8
106
104
106
TO
108
am
IM
in
73
100
169
197
1.8
99
,11
169
m
73
1<H
Pu
tnlroiptclioiu.
Po. Ammttig Incomplete.
Rg. A feeUng of ioconqjleteDCU.
Rk. Dinppnntuig.
Ho. Unfiiusbed, because of eipecUjicy of utother tocte.
Tft. lacoo^ilete. Thou^t you were trying to fool me.
Pu. Surpiised that there were not three. Incomplete.
The records from which Table 1 1 were prepared were taken
at the end of the year's experimenting because it was desired
to avoid the suspicious attitude which it might possibly have
induced in some observers. One of the details of method, it
will be recalled, was to let the observer know beforehand how
many tones were to be expected, in order to keep the conditions
in this respect as constant as possible. In this final experi-
ment, however, the observer was led to expect three tones,
but only two were given, the same two used in the experiment
just described. (Table lo). Any changes in rate of tapping
produced by unftUfiUed expectation ought then to become evi-
dent by a comparison of these two tables, 9 and 10, and indeed
Digilizcd by Google
46 W. VAN DYKB BISCBAM.
the difference is sufficiently striking. Instead of uniform
accelerations following the tones one finds retardations in
nearly every instance.
This, then, may aid us in understanding the accelerations so
frequently found where introspection reports that the interval
lacks finality. As a melodic interval it is left unfinished, but
in so far as the hearer was expecting a certain number of tones
and that expectation was fulfilled, the experience as a whole
gets a certain completeness and unity. Part, at least, of the
adjustments of attention have functioned as intended, and
only so much of the total motor attitude as was immediately
concerned with the tonality experience as such has to be re-ad-
justed when the melody comes to an end on what is not a final
tone.
The diminished fifth (45:64) was selected as an example
■of a group of two "unrelated" tones. The testimony of the
observers is nearly unanimous that the interval lacks complete-
ness and is dis^reeable to hear both ascending and descending.
(Tables 12 and 13.) Nevertheless there area lai^ernumber of
accelerations than of retardations. A comparison of the
"exceptions" with those in the introspective table clears up the
difficulty somewhat, but even then it must be said that this
pair of tables tells against our hypothesis. The only recourse
TABLE NO, 11
DtnanisM Fifth, ascmdinf. Average role by tkree-see«nd periods. Read acrott.
b
r
265
147
76
74
80
73
377
lis
78
7S
no
n
»67
ltd
SS3
73
76
J70
UT
»47
76
79
170
116
78
79
36s
Pu
H
Inlrosptelions.
Po. A n« rough Interval. AssodatioDS with Wagner nude it less diugtcesUe.
Incomplete.
Rg. Disagreeable because incomplete.
Ft. Not finished but good as fu as it went.
Ta. Unfinished but a pleasant interval.
Fu. Very disagreeable. Felt at entrance o[ second tone.
Digilizcd by Google
STUDIES IN MBIODY.
TABLE NO. a
asked Fifth, Jescetiding. Awarage rate by time-second periodt. Read aerois.
/'
6
J63
116
193
76
So
.76
118
78
79
117
77
J63
"S
J07
TO
79
J67
19B
7'
n
»7J
130
76
8a
J70
•31
74
is
»67
119
76
77
Po. Incomplete, but not seriously so.
Rg. One more tooe (he hummed c) would make a great difference.
Fr. Very unpleasant. It seemed complete because you told me there would be but
At fint thought it disagreeable, then not
Ta. Finished. A pleasant interval.
Pu. Didn't think about completenesi
is to the principle that the tapping tends to become rapid
whenever attention is freed from the stimulus, irrespective
of what the stimulus may be.
The descending major third is an emphatically final melody
(although Fr. and Pu. did not so describe it), and the table
(No. 14} shows the expected accelerations. The most inter-
esting feature is, however, the marked retardation in the
record of Rk. The last tone was a final tone, he said, but
he wanted a third tone in between the first and second, and
tried to figure out what tone that should be. The retarda-
tion occurs in the portion of the record where this was being
done.
In this and several of the following tables are given the
measurements of a single record in which the rate of each
separate tap is determined. Samples of the tapping of each
of the different observers are thus made available for detailed
inspection. It is interesting that the rate for individual taps
can fluctuate as widely as it does without greater variability
in the rate as measured for periods of three seconds.
The minor sixth (5 : 8) was, somewhat to the surprise of
the experimenter, judged to be an incomplete and disappoint-
ing melody, ascending as well as descending. It has the
Digilizcd by Google
W. YA« DYK.R BISCBAM.
Major Third, iacatdini.
177
i8i
187
161
198
191
ai8
178
149
148
106
148
181
i6S
181
101
i«S
'S3
148
346
IBs
177
tte
179
191
171
IS9
198
iSS
iSi
16*
18s
.76
i6>
j8)
171
176
183
■60
M9
181
.48
'53
169
>8a
'S3
190
in
'6.1
'S9
191
IS8
177
»7»
197
Ml
I3»
148
185
171
iSi
1S3
166
i>6
183
'«3
148
Attract rait
for eachOret-tecend peruxt. StadacroK
178
aJS
'93
80
171
103
>95
81
«8s
J»S
104
109
8s
i07
»i7
»
17
188
»19
97
106
80
188
106
213
88
'76
330
.06
19s
84
»37
Pu
86
Introtptctimu.
Rk. Wanted a third toiw UhM»m. Tried to dedde wtwt it should be.
Po. Surprising, but very udsfying. Fliwl.
Ho. It became satisfactniiy complete after I had thought about It.
Fr. Coheient, but suggested aomethiiig further.
Pu. Needed a third tone b
TABLE NO. It
ilinor Sixth, dtittHdim. ilttronomt rale of tach ttparaU lap. Read itimt.
103
106
"3
"S
119
'<H
109
«9
'OS
9>
103
117
119
81
96
los
101
110
I03
114
106
no
"7
"3
106
118
»9
97
106
89
AMragt rait by Urte-iicond periodt. Road «
f
b
13S
SKI
314
SM
3M
»i
»37
138
I3S
'39
t4S
180
104
106
113
108
108
98
17a
isi
181
I7S
183
'8.1
106
toi
'OS
'OS
107
100
lis
III
113
"4
"7
U8
DBiizcdb, Google
STUDIES IS MStODY.
Ititrosptttioru
Po. Surprise and disappointnieiit on teooud tone. Uiuatufactory.
Rk. E>oes not eod.
Ho. Very noticeably lacked finality.
Fr. Quite unrelated.
Ta. Tooe pteaaant but iDek>dy does not end.
Pu. Ungatiafactoty. Incomplete.
TABLE HO. II
UinorSatk,aKaidi»(. Melroitome rale of each stparaie tap. Rtaddawn
b
('
Ta
So
86
75
81
77
79
79
81
86
81
«3
7*
81
77
79
79
81
81
8,1
7a
79
Si
81
Si
81
81
83
73
71
86
81
75
Attragt role by liret-ieamd periods. Riadacron.
97
97
97
95
Introiptclions
Kg. No melody; do finality.
Ho. Seemed bad at first but changes to a final interval.
Fr. Unconnected and therefore unpleMant.
Ta. Incomplete.
Pu. Unrelated. The second note seemed to change in character.
character of incompleteness very strongly as a descending
interval, but when heard in the opposite direction itispossible
so to reconstruct the tonality as to make the higher tone a
tonic. This, the observers, with a single exception, failed
to do.
Consequently Tables 15 and 16 may both be taken as
showing the effects of a melody that lacks finality. The
unusually large number of retardations strikes the eye at a
glance.
§32 Turning now to some examples of three-tone groups
(tables 17 and 18), we are confronted at the outset with the
Digilizcd by Google
W. VAN DYKR BINCBAM.
difficulty that it is usually quite possible to interpret any
group of three related tones in a variety of ways, and we are
thrown back upon the introspections of the observers for a
starting point in our interpretation of the results. This
method has its obvious disadvantages, notably those result-
ing from the probably imperfect reports which the average
observer can give about so complex an experience as the
course of a three-tone melody.
TABLE NO. IT
Tkree- lone froufs. Attrage rate for each Ikree-teamd period. Rsai aeroit.
t
Rk
140
'43
I4>
143
"41
146
iSS
■47
141
Ho
111
iia
116
IM
117
118
116
llS
III
Ta
71
74 1
71
70
70
s?
as
75
7»
Pu
i»3
110 1
•35
U4
tiS
117
137
iji
138
Inlroipeclhtu
Rk. Finished. Very good mdody.
Ho. CoII^>lete, satisfactory.
Ta. Inoomi^ete.
Pu. Uncertain.
TABLE NO. IS
t
el^
frl>
Rk
..| ..V.
>3i
116
'Si
'3Q
iS^
170
139
1.16
Ho
118
113
'IS
lU
iiS
118
Ta
70
70
6S
C3
67
76
66
66
66
Pu
.. 145
144
154
138
141
'4S
lU
146
IS'
Introsptclimu
Rk. Leaves me in sublease.
Ho. Unfini^ied. Don't like it
Ta. Second note did not fit in at all. Very disconnected.
Pu. Fairly good ending, but the intervals are too wide.
The two melodies placed together here for comparison are
very similar in form, and both £ire made up of wide, conso-
nant intervals, but one of them, the first, seemed to the experi-
menter to have a more positive finality. The more mumcal
Digilizcd by Google
STUDtSS in MSIODT. Jt
observers ^ree with him in this. All of the retardations
(n^lecting of course those which accompany the entrance of
the first tone) occur at the end of the less final of the two
melodies.
On the whole these tables are not very illuminating.
TABLE NO. IS
Thrtt'iont poupi. Ateraft rale for taek tkret-iecond pvioi. Read across.
c' a b
Rk
Ho
T»
Pu
'54
"S
103
107
160
tog
71
los
104
70
96
'S9
1»
71
71
166
gf
70
too
179
70
"4
160
104
7»
Rk. Unsatisfactory. UusI go back to fint tone.
Ho. Periectly horridl Due to the lut tone.
Ta. Could give do tntro^KcUon. (Note regularity of n
Pu. IndiSerent.
TABLE NO. 10
Pu..
£'
a
fib
164
ite
'S9
'73
US
180
170
177
*S9
IS6
157
m
14S
146
'SS
171
178
180
tH
m
tSo
'ST
1S8
t8i
97
I03
106
104
w
103
101
100
77
80
77
n
7S
St
8^
78
97
99
98
too
m
111
IM
99
t. Rk. Wrong, but not very bad. Second note spoiled it.
1. Rk andsRk. (repetitions at a later date of some tones.) Both satisfactory and com-
plete, the latter reassuringly so.
Ha Last note predominates and becomes satisfactory ending.
Ta. Indifferent ending. Last note a disappaintmeDt.
Pu. Tones seemed disconnected.
Table 20 is of interest mainly because it shows the different
reactions which the same melody elicited from one of the
subjects at different times. The group of intervals, c'-a-bl»,
is one which demands a shift of tonality, but which then ends,
satisfactorily. When it was first given, Rk. did not so hear
the melody: the tonality did not become readjusted. Two
weeks later the experiment was repeated and this time the
tones were heard as a complete melody. It was immediately
given again, with similar but more positive introspective
Digilizcd by Google
71 W. VAK DrKE BINGBAM.
reports as the result. The three records show the expected
differences in the tapping.
A striking record is that of Ta. (Table 19). He tapped
throughout the course of the experiment almost with the
regularity of a ruling engine. When asked for an introspec*
tive report, he could find nothing to say! The tones had had
no effect whatever.
Every retardation shown in these tables (indsits explanation
in the introspective records. Not quite as much can be said
for all of the accelerations.
With table 21 we take up the study of the "Return." The
interval here used is the major second (8: 9). This is a very
satisfactory melodic figure when the lower tone is the start-
TABLE NO. It
Tkru-Ume group, iiajor taond. Avtrage rate for tack tkru-ttcond period. Read
95
91
'OS
103
Po. Second tone very lu^leawnt. Third reimtated calm and repose of the fint. At
loose cods OD second. The return cluoged all this.
Rk. Veiy unsatisfactory as a whole but had a (%rtaiD unity about iL
Ho. I think that ended nicdy. It b curious that I can not recall the middle tone.
Ta, The lower would have been a better ending.
Pu. Second note not right. Return to first gave feeling of finality.
TABLE NO. n
J59
j6.
=6S
sn
2H
261
SH
26s
161
1S8
181
IM
ue
m
m
193
"4
lOJ
no
97
too
99
too
93
114
106
lOI
to?
SB
102
70}
118
101
98
95
toS
lOO 1
Ta..
Pu..
Po. Third tone a pleasant rehef from suspense.
Rk. It was all right at the time.
Ho. Very pleasant and complete.
Ta. Positively finished.
Pu. Pleasant and complete.
Digilizcd by Google
STUDISS IS MBWDT.
ing point and the end, and one is not surprised to find a large
proportion of accelerations at the close. (See table 22, c'-
d'-c'.) The record fits well with the introspections.
When the upper tone is made the point of departure and
return, the melody tends to fall apart. The middle tone
positively will not fit into any tonality suggested by the first.
This appears very prominently in the introspective records.
Another feature is that without exception the observers felt
that the return from this lower tone to the upper was very
satisfactory. "The third reinstated the calm and repose of
the first," etc. The entire set of introspections accompany-
ing this table is recommended for careful perusal as clearly
setting forth the result of a return from a tone felt to be
foreign to the first. The experience acquires a unity which is
most certainly not contributed by any interval "relationship."
TABLE NO. S
Thne-Ume tfoufi. "Tk« Return." Aterafe rait for tatk Ikret-ticond ptrtMl. lUad
d r *>
Po
i8s
afo
»S4 1 ajJJ
SM
SS8
'48
>S6
>S8
'S4
161
t64 , 16S
160
tji
178
176
167
81
8l
81 { 78
79
78
74
76
84
99
loS
tio 1 96
no
»
"3
107
108
IntroapeetioTu.
Po. Much lesa complete th&a if uppd tone were last.
Rk. Satisfactory ending, but not so good as f-<-^ (hummed).
Ta, Fmished.
TABLE NO. M
/' c r
Po 149
149 249 ^ 236 ; »34 1 iS4
»}g
161
16}
Bg , "9
116
i2ti 1 133
1X7
US
126
13S
116
Rk 171
iSo
183 1 173
170
176
176
181
Ta 79
76
7S 1 73
70
73
7J
7S
76
Pu 81
86
87 1 90
86
90
101
97
96
Po. Emphatically final.
Rg. O. K. Finished.
Rk, Fairly satisfactory. More so than c-f-t (hiunmed).
Ta. Fairly complete.
Pu. Complete.
Digilizcd by Google
W. VAS DrKS aiSGBAM.
TABLB NO. H
Tkrtt-Unu tnmfs. "The ROurn."
Sou for each ttparoU lap. Read dawn.
«'
t
c'
Po
m
874
343
340
367
336
348
'36
3S'
»8s
167
346
m
'36
'S4
346
139
367
»S8
336
360
376
304
367
aOS
360
>i6
347
3,6
3sa
36,
"3
'46
*S«
131
339
353
376
»54
363
313
343
160
33a
321
363
361
369
336
339
'S4
»7a
1S»
334
348
367
378
'47
3S6
'S4
2tS
^S4
'S3
'33
360
350
360
36s
U3
36a
3.16
336
333
331
350
353
360
367
37b
Ml
336
as*
369
348
»33
356
340
171
334
JS«
376
377
334
370
350
373
369
333
343
373
356
33S
360
'S8
'S3
a;*
336
340
373
»S8
340
'34
346
'S4
Tkret-4oiutmipt. "TfteRaurn." A^erateraUbythree-itcoHdpmoit. Reaiat
tf
i
e
Po
368
3^8
aifl
'54
3^8
'48
'St
340
'S4
Rk
118
118
118
T18
wS
115
117
Ho
79
80
79
78
80
8i
93
9S
9S
308
303
3O0
»99
196
206
307
300
198
Inlrotpeeliotu.
Po. More or less complete. Not very good.
Ri. O. K. Finished.
Ho. Complete. Very pleasant.
Fr. Complete, but not wholly satisfactory.
A Study of the table of rates itself is equally illuminating.
In number and distribution of accelerations, it is almost
identical with the companion table, where the return was
from a tone felt to be quite coherent with the first tone of
the melody.
Tables 23-26 also show the effects of the return to the start-
ing point. The intervals used differ from the preceding in
that they are wider, and consonant intervals. The fourth
(tables 23 and 24) ends more emphatically upon the upper
note, the fifth (tables 25 and 26) on the lower. This was the
judgment of the observers. , The small sprinkling of retarda-
Digilizcd by Google
STDDtaS IM UEWDT.
tions at the close of these melodies would indicate that this
difference in finality is unable to maintain ttself,as against
the two factors that tend to exert an opposing influence upon
the tapping, the factors, namely, of the return, and of the
fact that the expected number of tones was heard and nothing
further anticipated.
TABLE NO. M
*' «'
i
no
118
77
74
*30
■38
78
197
74
W*5
»37
140
80
106
80
107
m
w.
79
"97
74
Utt
soe
140
77
us
73
'39
139
80
'9S
76
it6
340
lae
86
193
81
no
118
84
196
7S
Rk
Ho
81
to8
T»
P«
Fo. No feeling o( finality; therefore uopleatant.
Rk. Not as complete as e'-g'-c' (hummed), but one isn't left in suspense.
Ho. Can't say as to comidetcaesa. Unpleasant.
Ti. Inono^ete.
Ta. Better to end mi second note.
Pu. Not enqkhatic finality; only snch as any 'return' ^vca.
What of the octave? Meyer was unable to detect any
stronger "trend" to the lower than to the upper tone, and
consequently put himself on record as opposed to Lipps and
the other writers who assert that the lower tone possesses the
stronger finality.*
The question was put to each of my observers. They were
asked to judge with reference to the finality of ascendii^
octaves, descending octaves, and also groups of three tones,
involving the return. Intervals in the middle region of the
scaleand alsointhegreatoctave wereused. Theresults were
strongly j^ainst Meyer's view. Pu., the least musical of the
observers, could detect no difference in finality between the
end on the upper and the end on the lower of two tones an
" octave apart. All others found that a stronger feeling of
finality attached to the end on the lower tone. This dif-
' Psyck. Rev. 1900, 7, 148. In the light of Ms more recent studies on the efiect of
the faUing inflectioD (see above, p. 18) ire suspect that Meyer would today formulate
somewhat more guardedly his statements r^arding the psychological effect of the close
Digilizcd by Google
W. VAN DTKB BINCBAM.
ference of preference does not make itself evident, however,
in the tapping records of tables 27 and 28 (the octave). At
the close of the melody there is found almost exactly the same
preponderance of accelerations over retardations in each of
the two tables. Although one ending is better, both are good.
TABLE NO. IT
The OdoN. Rale of tack leparaU lap. Rtad d«tm.
Bl
90
93
96
88
8.1
79
81
8^
86
81
83
93
8S
93
83
9a
93
90
88
88
95
93
81
88
97
83
83
93
88
88
81
79
81
86
90
«S
Awrage rate for each tkret-teeond period. Read acrow.
88
88
93
as
89
8(
SB
88
>S8
ija
>S4
MB
SS8
*39
»S7
2s6
»38
23a
116
Ul
9H
MS
no
>i8
"9
IM
108
109
»
107
186
199
>99
305
ai6
807
106
»8
78
8t
78
n
71
73
77
81
96
93
98
109
III
UU
'"
110
TABLE NO. «
The OcUte. Kate of tack separate lap. Riod damn.
tr e
e"
Kg
93
96
9«
76
9S
90
94
88
98
9S
91
93
93
8.S
99
99
101
9"
90
90
93
89
88
88
90
9*
93
96
" 1 «
88
89
85
86
9>
9»
4. Raadaerott.
c" if
c"
93
94
93
8B
90
90
93
93
36t
177
W
2SS
«Sa
aH
as6
«■
ajo
»S9
a?6
a6a
160
JS9
ii68
107
to8
U8
97
t04
to6
III
198
199
19a
"S
116
VI
WS
m6
81
81
81
78
IS7
81
80
8t
130
138
116
111
114
114
124
i»
DiBiiizcdb, Google
STVDiaS IN UELODr. 77
§33 In the last two tables to be presented, Nos. 29 and
30, are shown the rates of tapping during the hearing of a
longer group of tones. Here the exact number of tones was
not told in advance, the observers being informed merely
that they might expect several more than the usual number.
The two "melodies" are alike in that they both start and
end with "c," and both use the same intermediate tones; but
they differ in the order of these tones. The firstgroup moves
slowly but naturally forward, and at length comes inevitably
to rest on the last of the seven tones. The second
moves as slowly and as regularly, and reaches the same goal, —
and yet the goal is not the same. Subjectively it is no goal
at all. None of the observers knew when it had been reached
until the tones abruptly ceased, whereas with the previous
group, all but one reported that they knew the last tone was
the last as soon as it began to sound. The first sequence,
then, is a genuine melody; the seoind is not.
One or two typical introspections may be quoted as repre-
sentative of the sort of experience which was more or less
common to all of the observers. Rk. {first seven-tone group.)
During the first three notes I did not know what was the melodic
■"""'"g or general direction, but on the fourth note it took sh^>e and
I anticyiated what the next would be, and 30 cm to the last. The Last
was definitely final. It didn't occur to me that there might have been
more tones until you suggested the possilulity of it
(Second group.) The third note was not what I expected. The
sixth would possibly have made a good ending. The last note was
a disappointment; it wasn't offensive, but obviously was not the best
possible.
None were satisfied with the ending of the second group
of tones; all thought it moreorless incoherent throughout and
hard to grasp. But with the first group every observer with
one exception was sure, when the last tone had been reached,
that that was to be the final tone. The one exception, Pu.,
could not give a definite answer to the question whether the
ending were a surprise or not, whether or not anything
fiuther was anticipated.
Digilizcd by Google
W. VAN DYKS BINGBAM.
TABLE NO. »
Group of lona judged So be a mdi>dy. Rate of tadt stparale lap. Read dawn.
c*
e'
t
e-
/'
(C
e'
Po
esi
».l8
3.,6
*,18
3S3
33S
331
3.18
3S8
338
3,1^
'48
'.16
146
138
ass
340
318
330
133
333
3S6
304
3S6
3.16
'.18
2SO
»,17
3.16
337
308
330
136
340
140
311
160
3.0
»S4
»,lo
3,16
»,17
346
308
3,1,1
118
SI8
»1I
186
«,11
346
118
350
",18
3.1«
330
aos
311
330
132
146
310
318
10
IM
118
3,,(.
3,13
311
33g
330
3S3
3t<t
2,16
3H
141
'S4
..rt
».,&
3SO
3.0
330
306
'.1,1
»,1.1
338
340
313
3lS
3,,6
>,«
M7
34t>
»S8
311
".M
110
».1I
s."
138
*,14
'44
3.16
..1!
346
"37
iii
20s
1.17
334
3.17
1,17
»4.'!
2.18
356
'S4
'It
117
3M
IS?
317
330
317
330
3M
trfi
336
34'
=.14
>.«
345
3SO
3S3
3,13
311
»3
310
«,18
a.l8
346
340
'.M
>.»
«6
»,rt
»S7
136
110
310
313
330
3.16
346
3.16
344
Averaff rate for each tknt-steotid period. Read <k
TABLE NO. M
Po...
. 160
Rr...
Rk...
■ »5'
Ho...
. I03
Pu...
■1 117
e'
r d'
f
e"
/'
e-
*,M
361
36B
276 am
380
338
364
«T
a6o
i!i%
36,
108
108
lOp 113
■ 13
I,*0
Ui
lOS
lOI
lO^
108
"53
los
161
,69
100
"7
172 168
110 : 112
t6S
M
163
113
106
11,T
m
"I
US
106
Its
IS3
I'S
171
In the tables the changes of rate are shown throughout the
course of the melody, but the ones which are of special
significance for our purposes are of course those accompany-
ing the strongly contrasted feelings at the end of the tonal
sequences. At the close of the first, every record reveals an
acceleration in the rate of tapping. In marked contrast are
Digilizcd by Google
STUDIES IN MBLODT.
the retardations found at the close of the other sequence.
(See accompanying graph. Fig. 3.)
FiGnxE No. 3. Effects of a Melodv and a Non-Mewjdy Contrasted.
Each tone sounded br thne seconds. Gnphs represent rate of tapping during each
of these three-second periods. Note general tendency toward increase in rate at
dose of melody, uid absence of such acceleration at close of non-melodic sequence.
§34 It remains to summarize and evaluate the foregoing
experimental data.
The facts which stand out with most prominence are, first
the correlation between the banning of a tonal sequence and
a drop in rate of tapping; second, the correlation, nearly as
close, between the conclusion of a tonal sequence and an
increase in rate in case the observer knows in advance how
many tones are to be expected ; third, the retardation of rate
at the end of a two-tone sequence when the observer has been
led to expect three tones, the sequence being one which under
the usual conditions produced acceleration instead of retarda-
donof rate; fourth, retardations at the close are much more
frequently encountered among those two-tone intervals which
Digilizcd by Google
W. VAK DYKE BIHGBAM.
are judged to be "unrelated", incoherent or decidedly " inconi'
plete,' ' than among intervals judged to be melodious, coherent
or chEiracterized by finality; (vid., especially, descending vs.
ascending fourth, ascending vs. descending fifth, minor sixth
vs. major third) ; fifth, the return to a first tone is felt as giv-
ing unity to a three-tone group, and retardations at the
close are not often met with, no matter how unrelated and
foreign the middle tone may have been ; sixth, longer sequences
of tones, the pitch relations of whose elements give to them
opposite characters as regards internal coherence and final-
ity, produce opposite effects upon the rate of tapping.
In an examination of our data, these six points come to
view. The attempts to apply our hypothecs in detail to
some of the results must be considered, however, simply as
indications toward a possible development of the method into
an analytic tool of much usefulness, rather than as brii^-
ing forward further positive evidence on the question of the
motor aspects of the perception of a melody.
Digilizcd by Google
SUGGESTIONS TOWARD A MOTOR THEORY OF MELODY.
Such evidence of the interconnection between muscular
activity and melody experience as has been here adduced is
too slender to serve as the support of an elaborate and detailed
theory. But the broad lines along which a motor theory
of melody must some day be worked out may be with pro-
priety suggested here, as harmonizing with the experimental
facts in so far as they are available.
535. Every melody, like every other experience which is
a ' whole,' must have, in Aristotelian phrase, " a beginning, a
middle and an end." A motor theory of melody finds the
'beginning' in the upsetting of established muscular tensions
which the onset of the tonal sequence involves.
The 'middle' includes the taking of the proper 'attitude, '
the organization of a set of incipient responses, and then as
the tonal sequence proceeds, the making of these responses
explicit and overt in the acts of responding to the successive
tones. Each tone demands a specific act of adjustment for
which a general and also a more or less specific preparation
has already been made, and each contributes in turn to the
further more definite organization of the total attitude. If
a tone appears which is of such a pitch that an entirely new
adjustment is necessary, that tone is unrelated: unity is
destroyed; the succession of tones is not a melody. But if
the new tone is so related to its predecessors that it institutes
a response which is in part a continuation of the act already
in progress, the unity is preserved.
The 'end' comes only with the arrival of a phase of the com-
plex ongoing activities in which the balanced tensions can
merge into each other and harmoniously resolve theiroppos-
ii^ strains. This becomes possible when a suflliciently defi-
Digilizcd by Google
83 W. VAN DtKB BtNGBAM,
nite set of expectations has been aroused and then sadsDed.
Here we find a reason why a close on the tonic has to be
'prepared for,' in musical phraseol(^;y, by a 'teadii^ tone'
not in the tonic chord. The expectations, the muscular
strains and tensions, must be developed to a certain degree
of definiteness of oi^anization before a return to the tonic
can serve as the cue for a general 'resolution.' 'Losung^
describes the close of the motor process somewhat better than
its English equivalent, relaxation. A single muscle can
relax. But this process of muscular Losuttg which marks the
end of a melodic phrase, a spoken sentence, or a rhythmical
period, is more than mere relaxation; it is an organized,
balanced muscular "resolution," to borrow a very apt tech-
nical term from the musicians.
Of some such 'beginning' and of some such 'end,' even so
crude and apparently remote a line of experimental attack
as the one we have used, has furnished an indication. In
order to learn about the nature of the 'middle ' muscular proc-
esses a more refined way of approach to the delicately com-
plex mechanism of the melody experience must be deVised.
One would like best of all to record the tensions of the laryn-
geal muscles when no sound is being emitted. Here doubt-
less is one of the centers, with many persons at least, of
those activities by means of which a series of separate musical
sounds is bound together into the unified experience we call
a melody. Already some few significant facts have been
accumulated regarding vocal tensions durit^ auditory stimu-
lation. Seashore and Cameron have independently demon-
strated that a vocal tone sung against an auditory distrac-
tion tends to vary toward a pitch which is consonant with
the distracting tone.*
Is this muscular process whose arousal and subsidence give
shape and unity to a melody, a rhythm? It certainly has
many of the earmarks of a rhythm, — its motor mechanism,
its relaxation following tension, its conscious aspect describ-
able as a satisfaction of expectation — all these would lead
> E. H. Ctinenw. "Tonal Reutioiu." PtycM. fict. Ueno. SuppUmmOs. 1907,
8, 187.
Digilizcd by Google
STUDIES IN MEWDY. 83
one to call it a sort of macro-rhythm, a giant process similar
in its essential nature to a rhythm in the usual sense. But
there are fundamental objections to such an identification,
chief of which are (l) that a rhythm involves repeatedly
recurrent stresses, with recognition of similarities, as this
'ground-swell' muscular process does not, and (2) that a
certain regularity, with possible variations between well-
defined limits only, is essential to rhythms. The two phenom-
ena, although both motor at basis, must not be confused.
The experimental study of rhythm has, however, disclosed
a motor phenomenon essentially like the large, basic motor
activity underlying a melodic unity. I refer to the particular
sort of muscular tension-relaxation process which Stetson*
found to be essential to the unity of a group of rhythmic ele-
ments felt to constitute a verse, or a rhythmic phrase.
Using a modification of the principle of the phonographic
recorder. Stetson made records of spoken verse, and measured
with microscope and micrometer the duration and the rela-
tive intensity of the separate syllables.
In unrhymed stanzas the duration of the verse pause was
found to vary widely, but it was invariably longer than the
foot pause. The typical dynamic shading of the verse was
found to be of the crescendo- diminuendo form. The intro-
duction of rhyme often shifted the climax of the crescendo
to the final foot by increasing the intensity of the rhymed
syllable. Although as great a verse pause was found to be
possible with rhyme as without it, the presence of rhyme
tended to shorten the verse pause, to bring the verse to a close
more rapidly.
WithiD the verse the general form of the syllable as it appears in the
mass of closely written vibrations often varies, but nearly always shows
a square end. Several veiy common shapes are Doticed and f^pear in
the record as 'truncated cones,' 'boxes' and 'truncated spindles.' . .
One syllable form has an espedal interest, because of its
bearing on the problem of ' finality ' feeling at the dose of the verse. At
the dose of each verse, whether with or without rhyme, the syllable
>R. H. Stetson. Rhythm and Rhyme. Uanard Ptyck. Studies, VoL L Ptyek.
Re*. Mono. Suppl. igo], 4, 413.
Digilizcd by Google
84 W. VAK DTKE BINGBAM.
fonn is always a 'cone.' Of about 600 verses measured not more than
15 are exceptions to this rule
The fotm very rarely occurs within the verse, and when it does it is
usually before some caesura, or under unusual conditions.
This 'cone' form of the closing syllable of the verse indicates a fall-
ing of the intensi^ of the voice. It is often, though not always, asso-
ciated with a fall in the pitch, showing relaxation of the vocal cords.
It seems to be an indication of the dying out of the intensity factor, a
sinking of the tension, at the dose of the verse. In the case of unrhymed
verses, with long verse pause, the cone is often very much elongated, and
it is quite impossible to say where the sound ceases.'
It will not be necessary to treat here of those portions of the
motor theory of rhythm which explain, as the central, or
"mental activity" theories have failed to do, the peculiar
nature of the various sorts of unit groups.' We shall briefly
sketch only so much of the theory as is requisite to explain
the larger groupings such as the phrase, the verse, the period.
Stetson's theory of rhythm assumes a movement cycle in-
volving the activity of two opposing sets of muscles. The
varying tension between these muscle sets as beat follows
beat never entirely disappears until the close is reached.
The continuity of the rhythmic series, whereby all the beats of a
period seem to belong to a single whole, is due to the continuity of the
muscle sensations involved and the continuous feeling of slight tendon
between the positive and negative muscle sets; nowhere within the period
does the feeling of strain die out.
But at the dose of the period we have a pause which is demon-
strably not a function of any of the intervals of the period. During this
pause the tension between the two sets 'dies out,' and we have a feelii^
of finality. This gradual dying out of the tension is clearly seen in the
constant appearance of the cone-shaped final syllable at the end of each
nonsense verse.
The period composed of a number of unit groups (the verse, in non-
sense syllables) has a general form which suggests strongly that it has
' L. e., 447-
' For a detenninatjOD and cqdaiutjoD of these peculiarities, such as the closer
proximity of the unacceoted to the accented beat in the iambic as coatiasted with the
trochaic foot, etc., cf,, StetsoD,"AMotot Theory of Rhythm and Discrete Si
Psych. RcB. IQOJ, ja, 393 ff.
Digilizcd by Google
STVDiES IN MBWDr. 85
the uni^ of a single co5rdiiiated movement. There is no more reason
for assuming a transcendental mental activity in the case of a rhythmic
period than in the case of a single act which appears in consciousness as
a muty At some point in the [>e-
riod there is a definite dimax, a chief accent; the movement 'rises' to
that point and then falls off. This is strikingly seen in nonsense veises
qmken with a heavy accent within the verse. The accent does not
stand out from a dead level, but the verse culminates at that point."
As a result of his previous study of perceived as opposed
to produced rhythms and especially the effects of rhyme and
of wide variations of tempo, — '1;^,' — introduced into differ-
ent portions of the verse and of the stanza, Stetson was led to
the conclusion that
there is some definite process at the end of the verse which marks
the dose of the verse and which takes more time in the case of blank verse
than in the case of rhymed verse. If we conceive the end of the verse as
a point where a dying out of the tension occurs, we may imagine that
the rhyme brings an emphasis, and becomes a qualitative signal for
this rdease. The slight increase of intensity on the rhyme contributes
to the breaking up of the coSrdination, and at the same time exhausts
and satisfies the feeling of tension which the verse embodies
A qualitative change may be supposed to produce the e0ect more rapidly
than the simple dying out of the tensions, which occurs in bUnk verse
without a differentiated end accent.'
This finality effect which rhyme augments is entirely analo-
gous with the finality phenomenon in melody. We have seen
that in three-tone sequences mere return to the original pitch
mayfumish thequalitative signal forthemuscular'resolution.'
If the hnal tone is not merely a repetition of the initial
tone, but has also the characteristics of a ' tonic, ' the com-
pletion of the finality process is much more definitely assured.
A third cause which sometimes operates to produce the
same effect is the mere satisfaction of expectation. If one
hears a certain irregular series of pitches, " related " or " unre-
lated, " often enough so that the final tone can be recognized
as such, one comes to feel that the group has a certain sort of
' Rkytkm and Kkyme, 4SS-
*L.C. t3i.
Digilizcd by Google
86 W. VAN DTKK BINGBAU.
unity even though there is neither a return to a starting point
nor an end on the tonic. The same holds true, to a certain
extent, with reference to an unfamiliar succession of tones
whose number is known in advance. If the observer is told
to expect four tones, a motor disposition or attitude is estab-
lished which constitutes a preparedness to react to four tones,
and if only three tones are heard, the finality effect may fail
to appear, although the third and final tone is at once a
tonic and a return to the pitch of the initial tone of the
sequence.
In each of these types of melodic finality, the closing tone
institutes a response which is not wholly a new reaction but
which is, on the contrary, the completion of an act already tn
progress. The feeling of finality arises only when the comple-
tion of the act issues in a muscular relaxation which is a dying
out of balanced tensions. The facts regarding those finality
effects which are due to the falling inflection also coincide with
such a view. Rise in pitch is not merely a result of increased
tension of the vocal apparatus: it likewise produces increased
muscular tension in the hearer. A falling inflection at the
close consequently serves to hasten the relaxation process
which marks the completion of the melody.
Finally, a motor theory of melody makes possible an unam-
biguous statement of the nature of melodic "relationship."
Two or more tones are felt to be " related " when there is com-
munity of organized response. "Unrelated" pitches fall
apart because each demands its own separate attentive act of
adjustment; but with "related" tones the attitude which
appears as a response to the first is a preparation for the
response to the second and is completed, not destroyed, by
that response. The feeling of "relationship" is the feeling
that arises when the tones elicit reactions which are in some
measure common. When, on the other hand, the first tone
calls up one set of associates and establishes a certain attitude
or organization of incipient tendencies, while the second tone
tends to call up a set of associates and establish an attitude
which is at variance with the first, there can be no adequacy of
coordinated response and the feeling of "relationship" is pre-
vented from arising.
Digilizcd by Google
STUDIES IK MBLODT. 87
The origin of these well-articulated responses which gener-
ate the feelings of "relationship" is not to be sought in a
single source. The operation of two main forces must he
distinguished — one of them sensory, the other associative.
The first of these, the phenomenon of consonance, is native
and doubtless has its basis in the relatively simple action of
the sensory apparatus in responding to auditory stimuli which
are mcM^ or less similar — are, indeed, in a measure identical.
But although the basis for consonance inheres in the inborn
structure of the nervous system and the acoustical properties
of vibrating bodies, nevertheless it isa commonplace of musi-
cal history and observation that these same native tendencies
are subject to tremendous modification in the course of experi-
ence. One race, one age hears as consonant intervals which
another age or race has never learned to tolerate; and within
the history of individuals it is easily observable that conso-
nance and dissonance are merely relative terms whose deno-
tation shifts with growing experience. Moreover the whole
complex group of phenomena we call tonality bears witness
to the f)ower of association to amplify and oi^anize these
native feelings.
But the associative factor or the factor of experience is
directly efficient in determining what tones shall be felt
as "related," quite apart from any effects which it has upon
judgments of consonance. Mere custom, mere habituation
to a certain succession of pitches results in a facility of recog-
nition and response which is capable of generating these
feelings of "relationship." The same kind of coordinated
reaction is instituted and this makes possible the same result-
ant feeling as that brought about by response to two succes-
sive consonant tones. The "relationship " is in both instances
traceable to the motor phase of the process.
The unity, then, which marks the difference between a mere
succession of discrete tonal stimuli and a melody, arises not
from the tones themselves: it is contributed by act of the
listener. When tone follows tone in such a manner that the
hearer can react adequately to each, when the response to
the successive members of the series is not a series of separate
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88 W. YAM BTKM MIMCaAM.
or conflicting acts but rather in each instance only a continu-
ation or further elaboration of an act already going forward,
then the tones are not felt as discrete, separate, independent,
but as "related" to each other. And when, finally, theseries
of tones comes to such a close that what has been a continuous
act of response is also brought to definite completion, the
balanced muscular "resolution" gives rise to the feeling of
finality, and the series is recognized as a unity, a whole, a
melody.
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Psychological Monographs
April, 1911
Wbck N*^ f I
Psychological Review
SDITMD BY
JOHN B. WATSON
JOHHI HoTKni DKtnMtTT
JAMES R. ANOEIX
Uhivihitt or Cbicaoo
Report of the Committee of the American Psycho-
logical Association on the Teaching of Psychology.
Presented to the Association December 29, 1909.
Committee :
Carl E. Seashore, Chairman
James R. Angell
Maiy Whiton Calkins
Edmund C. Sanford
Guy Montrose Whipple
Published by the Association.
THE REVIEW PUBLISHING COMPANY
41 NORTH QUEEN ST., LANCASTER, PA.
AND BALTIMORE, MD.
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DiBiiizcdb, Google
REPORT OF THE COMMITTEE ON THE TEACH-
ING OF PSYCHOLOGY.
To the Members of the American Psychohgical Assodaiion:
Your committee appointed a year ago to investigate and
report upon the teaching of psychology respectfully submits
its report herewith.
The committee at once limited its investigation to the
teiaching of the first year course in psychology; and, to secure
uniformity, this course was defined as a sophomore course run-
ning three hours a week throughout the year, or five hours a
week for one semester, whether this time is given to a single
course or to two.
The committee then resolved itself into three subcommittees
for the division of labor as follows:
1. The Normal Schools, Guy Montrose Whipple.
2. The Colleges without laboratories, Mary Whiton Cal-
kins.
3. TheColIegesandUniversitieswithlaboratories, Edmund
C. Sanford, James R. Angell.
Each of these subcommittees has circulated a questionary,
worked over the returns, and made certain recommendations
on the basis of these returns. E^ach of these four reports is
herewith presented entire and independent. The arrangement
represents the division of labor in the committee. No effort
has been made to reduce these individual contributions to
any formal committee report having the stamp of authority
either from the committee as a whole or from the Association.
Our aim has been to present a survey of existing conditions,
to bring t<^ether some of the most helpful hints for improve-
ment, and to stimulate interest and effective cooperation for
the advancement of the teaching of the first-year course in
psychology.
The committee tenders its most sincere thanks to all the
psychologists who have given their generous cooperation in
answering our inquiries.
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THE TEACHING OF PSYCHOLOGY IN NORMAL
SCHOOLS.
By Guy Montrose Whipple.
Comdl UnivertUy.
This report is based upon loo replies (84 from public, 16
from private normal schools), which were received in response
to a printed questionary, mailed to the 259 institutions (189
public, 70 private) listed as normal schools in the Report of
the United States Commissioner of Education for 1907.
The following states are not represented in my replies: —
Arkansas, Georgia, Indiana, Kentucky, Louisiana, Missouri,
New Hampshire, Oregon, Rhode Island, Tennessee, and Texas.
In the consideration of the items which follow, therefore, it
should be borne in mind that 1 1 state systems are unrepre-
sented, and that somewhat less than half of the existing institu-
tions have contributed data. At the same time, it is safe, I
believe, to regard this report as a fair representation of the pre-
sent status of psychology in our normal schools.
The printed questionary (with the omission of spaces left
for replies) is as follows:
QUESTIONS ON THE TEACHING OF PSYCHOLOGY IN NOR-
MAL SCHOOLS.
Please read all the questions before begirtrting to answer. When the space
allowed is insufficietU Jot your reply, phase attach extra sheets, but number
the replies thereon to correspond with the numbering of the questions. If
you can do so, mail me a catalog of your institution, and mark the courses
in psychology.
Name and location of institution.
Own name and title.
Address to which you irish printed rqiort sent.
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fsrcBouxsr in noxmal schools 3
A. GENERALADCOFWOBEINPSYCHOLOGY: ITSFLACEINTHECCKEICtJI.UH.
I. State concisely the general aim of the work in psychology, i. e.,
tell what it is designed to do for the students.
a. Do you give separate courses in general (or elementary) psychology
and in educational psychology, or are these combined in one course?
3. Do you offer any courses in experimental or laboratory psychology
in addition to those in general or educational psychology?
4. (a) Have you a psychological or psycho-educational laboratory?
(b) Xf not, have you any collection of psychological apparatus?
(c) What b the approximate value of th^ equipment?
(d) When was the laboratory established?
(e) Is it supported by a yearly appropriation? (f) How much?
(g) Has it separate rooms or is it united with other laboratories?
(N. B. In what follows, consider all courses in psychology.)
5. What is the length of the course or courses, *. e., number of exerdses
pet week, length of each exercise, number of weeks given?
6. Is the course elective (freely), or is it required? If the latter, of
what group of students (what year, course, etc)?
7. Is the course a prerequisite for other courses, e. g., psychology, prin-
dfdes of education, methods, practise-teaching, etc.? (Please submit a
brief outline showing these interrelations.)
8. What is the average number of students registered in the several
courses in psychology each year?
B. METHOD OF COKDUCTING THE WORK.
9. Do you use a r^ular text-book or books? If so, what?
10. Does the work in psychology center chiefly about l^e text-book
(recitations, discussions, etc.)?
II. If you use any of the following devices, indicate approximatdy
the rdative amount of time devoted to their use:
(a) Lectures by the teacher.
(6) Demonstrations by the teacher.
(c) Experiments by students (give examines).
(d) Class discussion of text or lectures.
(e) Dictation by the teacher, to be taken down verbatim by students.
(J) Written exercises of various sorts.
(g) Exercises demanding introspection by students.
(A) Exercises demanding observation of others.
(t) Outside reading by students in books other than the text-boc^
(Required of all students or assigned individually for report?
If confined to a few books, please name these.)
(j) Personal appointments with individual students to discuss dif-
ficulties, etc.
(i) Printed or mimeographed lists of questions or outlines for use by
students to chedk up their knowledge of the course. (If feas*
iUe, send a copy, or state where it may be bought.)
(0 Any other devices.
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4 car MONTKOSE WBIPPLE
13. Of the devices justmentioned, which is most valuable in aiding the
students to assimilate the work?
13. If you give any demonstrations in class, submit a list of these.
14. Mention any pieces of apparatus that you consider eqwdaUy use-
ful for illustration or demonstration-work.
15. Is the class period ever used merely as a study-period, or is all
study done outside of the classroom?
16. If you give lectures, do these merely illustrate and explain the text-
book, or do they develop topics not mentioned in the text?
17. Upon what is the final grade of the student determined, — recita-
tions, exercises, examination on the text-book, or what? (Please en-
dose a sample set of examination questions.)
18. Does the class always meet as a whole, or at times in sections? Is
it ever quizzed by assistants or by anyone other than the regular teacher?
19. Do you have lectures on psychological topics given at your insti-
tution by persons not connected with your faculty? Is there any regular
system of such lectures?
C. CONTENTS OP COUBSES.
{Note. If you faUow exactly Ike topics and conietUs of a textbook, U may
not be necessary to answer questions in this Section in detail.)
30. Submit an outline of the topics given or discussed, lecture by
lecture, e. g., (1) nature of psychology, (2) nervous system, etc.
31. Please iiulicate as nearly as possible the absolute (or relative) time
that is devoted to the following topics:
(d) Development of notions of scientific method (meaning of experi-
ment, introq>ection, etc.).
{b) Quad-pbilosophical problems, such as the relation of mind and
body, nature of mind, biological significance of consciousness,
etc.
(c) Anatomy and physiology of the central nervous system.
{d) Psychology of sensation (including structure of the sense-
organs).
(e) Attention (including interest).
(f) Affective processes, feeling, and emotion.
(e) Reflexes and instincts.
(a) Psychology of learning, habit, educative processes.
(i) Complex forms of action, e. g., impulsive, selective, volitional,
etc.
(j) Association.
(k) Perception (including observation).
(l) Memory.
(m) Imagination.
(«) Conception, judging, and reasoning.
(0) Problems of mental development, such as inheritance, contata
of children's minds, adolescence, and other child-study t<^cs.
(p) Individual differences of all kinds.
iqj Animal psychology.
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FSTCBOUXT in SOKMAL SCHOOLS
fy) Borderline phenomena, such as hypnotism, sleep, dreams, psy-
chotherapy, etc.
(s) Any other topics, such as hygiene of the sense-oi^ans, fatigue,
psychology of primitive peoples, etc.
as. Do you give instruction in other courses than psychology? If so,
in what?
23. Is there more than one teacher directly or indirectly engaged in
giving instruction in psychology?
34. Do you attempt to do any original work in psychology? If so,
are you aided by students?
35. Enumerate any studies (magazine articles, books, etc.) on psycho-
logical topics published by you or by your pupUs in the institution.
a6. Where did you receive your training in psychology?
2j. What degrees do you hold, or what diplomas or certificates have you
received?
38. How long have you taught psychology?
E. RESULTS, DIFnCTTLTIES, POSSIBLE IHFSOVEUENTS.
39. Do the students display distinct interest in psychology? In what
way?
30. Enumerate the ways in which you think the work in psychology
helps the students in their work as teachers.
31. Inpresenting the subject, do you encounter any difficulties that the
text-book does not resolve? What are they?
3 2 . If you had a free hand, would you make any changes in your present
methods of teaching psychology, and if so, what changes?
33. In what ways could this Committee be of assistance to you in your
work?
F. KEUASKS.
Kindly add any remai^ that would assist us in understanding the
status of the teaching of psychology in your institution.
Before listing the replies to the questionary in detail, a
bird's-eye view of the teaching of psychology in the normal
school may be of value. Such a view may be secured by de-
scribing, on the basis of the data submitted, the condition of
psychology in the typical (or average) institution.
In this typical institution, then, the teacher has received his
training froiii an American college, and holds a bachelor's,
and possibly also an advanced d^;ree. He has taught psy-
chology for 8.5 years, has sole charge of the courses therein,
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CU¥ MONTROSE WHIPPLE
and, in addition, gives instruction in certain courses in educa-
tion.
His class of 107 pupils demands much time and energy, and
other circumstances, such as scanty library and laboratory
facilities and the immaturity of his pupils, conspire to render
it difficult or impossible for him to prosecute original work, or
to keep pace with the contributions of others.
In teaching psychology, he encounters difficulties, due in
part possibly to his own lack of preparation, in part to the im-
maturity of his pupils, in part to the inherent complexity of
the subject-matter, but more especially (at least in his opinion)
to the inadequacy of the available text-books.
He is, of course, anxious to improvehis instruction : he would
would like to know what the instructors in other schools are
doing in psychology, and would be glad to receive helpful
suggestions concerning the arrangements and conduct of his
course. If he could, he would extend the time given to psy-
chology, and would work out more satisfactory correlations
between the work in psychology and that in biolc^y and in
education.
The coui^e he gives in psychology is a combination of gen-
eral and educational psychology: it is required of all students
as a prerequisite for subsequent or concurrent work in edu-
cation,— especially in the study of methods and in practise-
teaching. The class meets in one section for 45-minute pe-
riods. In all, 90 (actual) hours are devoted to the subject.
The typical teacher £ums to give his pupils general familiar-
ity with the laws and operations of mental life, with the par-
ticular idea of rendering this knowledge practical and useful in
the life work of the teacher, and he firmly believes that this
result is attained, — that those who have had psychology have
gained a sympathetic knowledge of the child's mental life, that
they appreciate the rationale of methods, and teach more skill-
fully. Whether the students are at the time convinced of the
serviceability of their study of psychology is, perhaps, an open
question. Probably about half the class exhibit interest: the
other half take the course because they must, and in so far, the
teacher is always conscious of the necessity of striving to make
psycholc^y at once attractive and practical.
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MTcaoLOcr is sosmal scbools
The content of the course is determined almost entirely by
the text-book (probably some one of the volumes of Angell,
Halleck, James, Thomdike or Titchener). This text may or
may not distribute the emphasis upon those topics that are
most significant for education. The chances are that too
much time is paid to the nervous system and not enough to
habit, the inheritance and acquisition of capacities, and other
features of the educative process. The chances are, however,
that the distribution of time in any single institution does
not coincide with that in any other institution.
In presenting psychology, the teacher relies m^nly on the
text-book: he lectures only occasionally, and in an informal
manner, either upon topics discussed or topics not discussed
by the text.
All studying is done outside the classroom.
The very few demonstrations that are given are confined
to the nervous system, central or peripheral.
The student performs few or no experiments for himself,
and is not properly trained in introspection; he may submit
occasional reports of observation upon the children or the
teaching in the practise school.
Discussion in the class is a feature of the course and there is
a reasonable amount of as^gned outside reading, both of
which devices are regarded as valuable adjuncts of the course.
These exercises are supplemented by fairly frequent written
Qcerdses, — themes, tests, etc.
The chances are about even that the teacher hasoccasional
personal appointments, especially with those students whose
work is below par. The chances are that he does not use
formal dictation, or printed outiines, or quiz-lists.
Finally, in our 'typical' normal school there is no psycho-
Ic^cal or educational laboratory, and probably not even a
collection of apparatus. If such a collection exists, it is
probably confined to a few models, charts, or lantern slides
of the nervous system, or to a few 'show-pieces' like the
ei^c^raph, the color-mixer, or a simple reaction-time appara-
tus.
With this glance at the condition of psychology in an aver-
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8 CVY MOITTICOSE WBlfetK
a^e normal school, we may. now consider the statistical results
of the inquiry as exhibited by the returns from the lOO insti-
tutions.
For convenience of discussion, the order of presentation
will depart from that embodied in the questionary. Atten-
tion is asked (A) to the teachers (their training, opportunities,
difficulties and desires), (B) to the place of psychology in
the curriculum, (C) to the aim and success attained in teach-
ing psychology, (D) to the content of the course, (E) to the
method of conducting it, (F) to the use of experimental or
laboratory work, (G) to a number of conclusions and sugges-
tions.
A. THE TEACHERS
I. Their academic status
Question 27. Degrees. Of the loo teachers 8i reported
collegiate degrees. These include 64 Bachelor's, 47 Master's,
and 32 Doctor's degrees, besides 2 Medical and 3 Honorary
degrees. Five hold only normal-school diplomas, or state
or other certificates.
Question 26. Institutions at wkick training in psychology
was received. Aside from 20 normal schools, training in
psychology is reported as follows; at Chicago, 19; Columbia,
14; Clark, 13; Harvard, 11; Michigan, 8; Indiana, 5; Penn-
sylvania, 4; 3 each at California, Jena, Leipzig, New York
University, Iowa, Wisconsin, and Yale; 2 each at Berlin,
Cornell, Gdttingen, Illinois, Minnesota, Stanford, Zurich;
I each at Adelbert, Albion, Amherst, Bryn Mawr, Columbian,
Cumberland, Edinburg, Erskine, Halle, Hamline, Hillsdale,
Hobart, Howard, Illinois College, Kansas, Lafayette, Lebanon,
Nebraska, Northern University, Oberlin, Pennsylvania State
College, Smith, Toronto, Tennessee, Tufts, University of the
City of New York, University of Nashville, University of
North Carolina, Wellesley, and Yankton College. In many
cases the teacher had attended two or more institutions of col-
legiate rank.
Question 28. Length of time the teacher has taught psy-
chology. The replies to the question; "How long have you
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rsrcBowar in normal schools g
taught psychology?" are summarized in Table I, whence it
is evident that teaching-experience ranges from one term to
26 years. If we disregard the tendency to give the nearest
5-year multiple, — a tendency which has obviously distorted
the frequencies at 5, 10, 20, and possibly- at 15 years, — we
may determine the average teaching-experience at 8.5 years.
Table i.
Teaching-Experience, in Years, of Normal School Teachers o( Psychology.
Years...! 1234 s 6 7 S 9 10 It II 15 17 18 20 25 j6
Number., 3 565? i" 3671 14 6 7 2 2 4 $ • ■
Question 23. Number teaching psychology in each school.
But 43 replies were made to this query. Since, presumably,
lack of reply indicates that but one teacher is engaged in
psychology, we may, by adding 9 replies of 'one only,' con-
clude that in 65 of the 100 schools, the work in psychology is
given by a single teacher. In 18 schools there are 2 teachers
of psychology, in 7 schools 3 teachers, in i school 4 teachers
in 6 there is more than one teacher, but the number is not
stated.
Question 22. Number giving other instruction than in psy-
chology. In the typical normal school, not only is there but
one teacher of psychology, but this teacher is also in charge
of instruction in other, often quite unrelated subjects. To
be specific, 78 of the 100 teachers give instruction in courses
other than psychology. This additional instruction is com-
monly concerned with some phase of pedagogy or with logic
and ethics, as the following figures indicate:
31 History of education. 3 Child-study.
30 Pedagogy or 'education.' 3 Biology.
t4 Methods. 3 Phyacs.
13 School administration or school 3 Latin.
management. 3 Economics.
II Ethics. 3 Philosophy of education.
10 Logic. 3 Algebra. -
8 Principles of education. i Arithmetic.
6 Literature. i Astronomy.
6 Histoiy. I Botany.
4 English. I Chemistry.
4 School law. I Critic teadung.
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lO GUr UONTBOSB WBIPPLK
4 Civics. I Kinderg&rten methods.
3 Philosophy. i Manual training.
3 Physiology. i School hygiene.
3 Geography. i Seconda^ education.
I Zo5logy.
Question 24. Original work attempt^. Of the lOO teachers
who reported, 22 attempt to do some form of research work,
in which 7 of them are aided by seniors or selected pupils.
But most of these 22 state that in the normal-school environ-
ment it is hard to get the time, energy, or incentive to do such
work.'
Question 2S. Publications by teacher or pupils. Twenty-
seven normal-school teachers have published articles or books
upon psychological topics. In several instances, however, the
titles mentioned are those of doctorate theses or other studies
prepared by the teacher in the university or at least outside of
the normal school. It appears again, therefore, that only in a
few exceptional institutions are the conditions (whether of
teaching staff or institutional routine) such as to favor cre-
ative work.
2. Their difficulties and desires.
Question 31. Difficulties encountered in teaching psychol-
ogy. Difficulties are attributed (a) to the pupil, (b) to the
teacher himself, (c) to the inherent complexity of certain top-
ics, and (d) to the text-book.
'The writer is impresMd with the bet thst the (^>portuiiity ^qiuently open to the
normil-Khool teacher of psychology to conduct eqieriments on 4 Unge scale in regaid
to the application in classroom teaching of psychological principles, >. «., the opportunity
to indulge in experimental pedagogy-is not, for one reason or another, adequately utili-
zed. The model, practice, and observation dassea attached to the normal schools would
seem to offer a rich field for experimental work of this kind. The most obvious difficulty
is, presumably, the lack of properly trained students, and the short time availaUe in
the average nonnal-school course, which puts pressure on the teacher to concentrate
his attention upon the work of teaching his pupils the elementary facts of psydiology.
But there are a limited number of normal schools that aspire to the dignity of "Normal
Collies "and that even grant an A.B. degree. Here, with high-school preparation of all
students and a four-year profesuonal course, there should be a place lor valuable experi-
mental woA.
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fSYCBOLOcr m sokmal schools i i
(a) The pupil is said to be too immature (2)* or disin-
clined to think, to be willing to mjister the text, but not the
subject.
(d) Only two teachers attribute their difficulties in some
measure to themselves. One teacher does not feel sure what
ought or what could be taught in psychology in the normal
school : another regrets his inability to keep up with the litera-
ture of the subject.
(c) Special difficulty is reported with heredity, the theory
of evolution, the psychol(^y of hearing, the affective pro-
cesses, the "physiolc^cal side," the nervous system, the
history of psychology, volition, the hygiene of study, the
functional point of view, the tendency to confuse the mental
and the physical. Five teachers say that the principal
difficulty is that of so adapting psychology that it shall bear
on the daily life of the pupils and particularly upon the work
of teaching. Two believe that the absence of a laboratory
equipment makes their work more difficult.
(d) But the text-book is evidently the bite-noire of the
normal-school teacher, although at the same time, as will be
seen later, it is a main reliance in his teaching. The text-
book is said to have too few historical sketches, to be too
vague, too abstract (5), too difficult (6), too technical in
terminology (5). It fails to show the bearing of psychology
upon conduct, and fails to make proper use of the student as
his own laboratory {3). "The scientific texts are too hard:
the easy texts are not scientific. " Those at present on the
market are declared to be "the pedag(^cal blunders of great
scientists who know enough psycholc^y to write a book, but
not enough to understand the mind of the high-school graduate.
Again, it is remarked that " the text-book doesn't resolve any
difficulties: it makes them."
Question 33. How assistance could berendered. The normal-
school teachers think that they could be best helped in their
work (a) by the preparation and circulation of reports such
'Numben in parentheses following duaificatoir data in this and other pangr^du
refer to the niunber of reports in triiich the data appear, but irtiere an itemiamentioaed
but once the number has been frequently omitted.
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1 1 Gur MONmosE wbifflk
as the present one, because they "want to know what others
are doing" (incidentally, a few desire that this report be sent
to their state superintendent of public instruction or to those
that prepare the state examinations in psychology), (6) by
extending suggestions as to the arrangement and conduct of
courses in psychology, (d) by giving attention to the text-
book evil, and (e) in miscellaneous ways.
(b) The desire (or help in the conduct of oiurses may be
evidenced by the following quotations: "Outline for us a
laboratory course, giving a list of apparatus, maker, cost,
etc." "Outline a course in educational psychology, with
experiments and apparatus" (2). "Outline a two-year
course in normal-school psychology, recommending texts, and
supplying a bibliography." "Outline a 20-weeks course in
psychology." "Show us how to teach psychology to 16-
year old pupils." "Set standards for this kind of work.
Show us the essentials" (3). "Suggest books on the psy-
chology of method," etc.
(d) Five teachers beg the Committee to write "a decent
text-book. " The characteristics of such a text are also speci-
fied by several correspondents: it should be "aliving, working
psychology," "one that is free from scientific 3lang,"(!) "one
that treats of psychology as personal experience," and "a
sensible one for beginners."
(e) Other suggestions of ways of assistance are : " Develop
cooperation between university and normal-school teachers. "
"Find out from teachers who have graduated from normal
schools what work In psychology was actually helpful to
them." Some teachers ask for specific information, e.g.,
"Give me some scientific information about the relation of
blood to brain activity." "Tell me if there are any psycho-
logical differences between the whites and the colored race."
Question 32. Changes desired. The changes that would
be made by the teachers of psychology, if they had a free
hand, relate in the main either (a) to the place of psychology
in the curriculum and its relation to other branches, or (ft)
to the content or method of the course.
(a) The crying need is that of more time (11). It is also
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rsTCBOLOcr in NOKMAL SCSOOLS 13
desired to defer psychology until the last year (3), or to divide
the work into two courses, an elementary and an
advanced (3). The wish is expressed, also, for better articu-
lation with biology (3), physiology (3), pedagogy, school
hygiene, methods, and practise teaching.
{b) So far as alteration of content or method of presenta-
tion is concerned, it is significant that 19 wish to introduce
laboratory or experimental work. Seven wish to give more
exercises in the observation of children, 4 to "emphasize the
genetic side," e.g., by adding a course in child-study, 4 to
give more demonstrations in class, 3 to work more by the
inductive method. Other desired changes are to emphasize
social psychology, philosophy, religion, and mental hygiene,
to provide more reference books, to institute more group work,
more conferences with students, to give intensive work on a
few important topics, to increase the teaching staff, and to
provide a vacant period after each recitation for use in dis-
cussion, conferences, experiments, etc.
B. THE PLACE OP PSYCHOLOGY IN THE CURRICXn.tTU.
Question 8. Number of students. Restricting considera-
tion where more than one course is offered to the introductory
or first general course in psychology, we find that 90 institu-
tions report 9,669 students in psychology, an average per
class of 107.3 (in.v. 68.6). The largest number is 500, at
Ypsilanti, Michigan;thesmallest5,attheJ. K. Birch [Private]
School, Enfield, N. C.
Question 18. Meeting in sections or as a whole? In 71
schools the psychology class meets as a whole; in 14 it meets
in 2, 3, 6, 8 or 9 sections. In 6 institutions the class meets
occasionally in sections, e.g., for laboratory, or some form of
advanced work.
Question 2. Elementary and educational psychology com-
bined or separate? The 97 replies show that these courses are
combined in 67, separated in 30 institutions.
Question 6. Elective or required course? Only 6 schools
report elective courses. These courses may be taken after
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14 GVF MOr/TSOSE WBIPPLB
the introductory course in general psychology (including
usually educational psycholt^y), and are devoted to such
phases as physiological, genetic, or abnormal psychology, or
'mental hygiene.'
Question 6 (ctmtinued). Required of what group of students?
It is impossible from the data at hand to draw reliable con-
clusions upon this point, both because practise evidently
differs widely in different institutions, and because the normal-
school course varies from i to 4 years in length, and the
descriptive terms "2d year," "Junior," "Sophomores," etc.,
have no meaning unless a catalogue of every school is at hand '
to discover their significance. From appended remarks,
however, it is clear that two factors are at work, (l) a desire
to postpone psycholt^y as late as possible in order that
students may be more mature and experienced, and (a) a
desire to introduce it earlier so that it may serve as a basis for
the study of method, and for observation-work and practise-
teaching. Even when psychology is deferred to the final year
of the normal-school course, it precedes or accompanies the
courses and work just mentioned. In a few schools a very
elementary course is given in the first and a more systematic
course in the last year, — a procedure which evidently aims at
the accomplishment of both of the desires cited.
Question 7. Psychology a prerequisite for what courses?
As has been noted, psychology in the normal schools is a
required subject and must commonly precede certain other
courses. In the68 replies received to Question7,thesesequent
courses are specified as follows : practise- teaching (48) , general
or special method (29), pedagogy in general (17), history of
education (13), principles of education (12), observation
work (9), supervision or school man^ement (9), philosophy
of education (6), advanced psychology (3), child-study (3),
moral philosophy (i).
Question 5. Length of the course. The length of each daily
exercise in psychology was reported by 83 institutions. From
the accompanying distribution (Table 2) it is clear that 40-
45 minutes is the typical class period in the normal school.
The few cases of 90-minute exercises presumably refer to
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psrcBOLoar in nokmal schools
laboratory or demonstration periods or to exerdses given
over partly to observations, discussions, etc.
Tabu 3.
Number of Minutea Devoted to CIui Period* in Psycbcdogy.
In 81 reports, the data were sufficient to enable the compu-
tation (with a possible error of some 5 per cent) of the total
time (in 60-minute hours) given to psychol(^y. The results
are; average time, 90 hours (m.v. 34); maximum, 270 hours
(3 years, 120 weeks, at the State Normal School, Albany,
N. Y.); minimum, 22.5 hours, (10 weeks, three 45-minute
periods each, at the State Normal School, Danbury, Conn.).
These extremes and the large mean variation of the averse
indicate that there exists litUe ^reement in normal schools
with regard to the time to be devoted to psychology.
C. THE AIM IN TEACHING PSYCHOLOGY AND ITS REALIZATION.
Question 1. General aim of the course. The usual answers
are: the aim of psychology is to give a general familiarity
with the operations and the laws of mental activity (28) in
such a manner as to afford a satisfactory basis for the art of
teaching (75). Less frequentiy is the aim considered to be the
supplying of general culture (19). The introductory course
is often conducted primarily as the basis for further study
of advanced psychology (22). In a few instances (3), the
aim is frankly stated to be the satisfaction of legal require-
ments.
Question 29. Interest displayed by students. Of 54 replies,
distinct interest is reported in 50, interest on the part of a few
students in 4 cases. It may be fair to assume that in the 46
institutions that fail to reply, little interest is shown in psy-
chology. When it is displayed, interest is said to be mani-
fested by questions, by participation in discussioBS aad
debates (21), by the voluntary assumption of studyand lead-
ing beyond the class assignments (14), by the appUcatiaa of
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t(i GVY MOKTKOSR WBIPPLE
psychological principles in practise- teaching (9), by general
good work and zeal in the classroom (5), by the election ci
non<required advanced courses (3), by continuing to study
psychol(^^ after graduation (2), by acknowledging help from
psychology in other studies (2), by acknowledging a changed
attitude toward books, people, and life in general (2).
Question 30. How psychology helps students in their work
as teachers. As already noted, a primary aim in normal-
school psychology is to afford a basis for the art of teaching.
It is evident that as a rule, the teachers of psychology, believe
that this aim is attained, though not to the degree that might
be wished. We have, unfortunately, no information from
the graduates of the schools themselves as to the value they
have gained from psychology: according, however, to the
school authorities, psycholc^y gives teachers greater sym-
pathy, tolerance, and patience (10) , enables them to teach more
intelligentiy, scientifically and skillfully (8), especially because
they know how to organize or plan their work, (8) and see the
reasons for the devices and rules of method (6), which now
become guides instead of rules, so that teaching becomes a
profession instead of a trade (2). Psycholc^y develops
thoughtfulness (2), an investigating spirit (2), and common-
sense (i); it prevents sentimentalism, makes students more
critical (i), in that they search for causes and know what
proof is (i); it makes them also more observant (2), more
confident (i), more tactful (i), more progressive (i). It
''pves a safe attitude toward mental processes" (1), and
makes a saner disciplinarian (i).^
Psycholt^y is calculated also to improve the relation of the
teacher to the child, since the teacher who has studied psy-
(Aology has a better understanding of the child's nature (7),
knows what to expect and what not to expect of children (6),
and appreciates individual differences in children (6).
■Id the irords of one enthusiutic teacher: "If the great truths presented thereiiiu«
Gompreheiided, the teacher is enabled to see life as a compact whole, with all itt mem-
bers bound tx>Kether by a common Creator, common tenqitations, and a common des-
tiny. He is able to rise above the petty vexatious things of every-day life to the serene
hdghts attained only by those who can see from the beginning to the end the plan of
an all-wise Creator working itself out to a glorious triumphant endingl"
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PSrCBOWCr IN NOKMAL SCHOOLS IJ
Again, psychology renders assistance because it makes
clear the real nature of the educative process (2), particularly
of the process of learning (1), and shows the teacher how to
develop concepts (l), how to develop ideals and motives (i),
how to secure independent work by pupils (i), and how to
utilize play, imitation, suggestion, and other instinctive ten-
dencies.
By showing the physical conditions of mental life, psy-
cholc^y enables teachers to understand mental hygiene (3).
It is said both to "get students away from books," and to
"enable them to understand pedagogical literature."
" It induces organization with reference to development of
children, school hygiene-nature and value of subject-matter,
means of communication, personal and social control "(i).
D. THE CONTENT OF THE COURSE IN PSYCHOLOGY.
Question 20. Outline of topics presented. Only 8 outlines
were submitted in response to this query. These have been
subsumed under Question 2 1 . One institution follows a state
syllabus: several institutions shift the contents of the course
from year to year: 27 follow a prescribed text-book for the
content, and of the 60-odd institutions that remain, the
majority may be assumed to follow a text*book, so that the
content of the course is best indicated in the list of texts that
follows.
Question 9. Text-book used? If so, what? (a) No text
is used in 5 institutions, a single text-book in 34, two texts in
26, three texts in 15, four or more texts in 12 institutions.
Many teachers assert emphatically that no one should attempt
to teach psychology with but a single text-book, and it is
probable that, of the 34 that use only a single text, there is
more or less use of other books for collateral reading.
(b) Classification of texts used in normal schools.
If we divide the texts, as reported, into three groups, we
obtain the following distribution: (i) extensively used, —
Angell, Halleck, James, Thomdike, Titchener; (2) less exten-
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I8 GDV MOSTSOSR WBtfPLS
sively used, — Betts, Dexter and Garlick, Gordy, Kirkpatrick
Salisbury, Witmer, (3) used only occasionally, — Baker, Bald-
win, Binet, Buelt, Davis, Deatrick, Dewey, Hall, Hannahs,
Harris, Hill, Home, Huey,Judd, Ladd, Maher, McLellan,
Morgan, Putnam, Ribot, Roark, Sanford, Seashore, Stout,
Sully, Tracy, White.
It is to be understood, of course, that many institutions
that use one of these books for a text make more or less use
of others for outside reading, especially of texts on experi-
mental work, such as Judd, Seashore, Sanford, Titchener,
Witmer. Use is made also of Baldwin's Dictionary of Psychol-
ogy and of texts in neurology and physiology.
Question 2 1 . Distribution of time to the several topics within
the course. Because the majority of teachers follow the dis-
tribution found in the text-book at hand it is well-nigh impos-
sible to present a satisfactory picture of the distribution of
time in normal schools to the several topics that comprise
the usual course in psychology. Unless these text-books are
collected and examined, the status of the courses in which they
are used cannot be reduced to quantitative terms, and the
difficulty of this task has seemed out of proportion to the
probable value of the results that would be obtained. In
some 35 cases, the classification embodied in the quesdonary
has been utilized, and these data have been summarized in
Table 3.»
Perhaps the most interesting feature of this Table is the
divergence that it reveals in the extent of time that different
institutions devote to the several topics. This divergence is,
of course, due in large part to the divergence already noted in
the total amount of time devoted to psychology, yet it seems
worth while to accentuate the variability in the allotment of
'Id ezpUnatioii of this Table, it should be uid tlut the data were submitted ia abto-
lute, ia icUtive, and in descriptive teims. Where the distribution of time was indicated
as a fraction of the totiU time, this has been recalculated by reference to the data sap-
plied under Question 5 lo that it might be stated in absolute units. The descriptive
terms have been reduced to three groiqM, (i) "incidental," "brief," or "very little,"
{») "■ome,""occaMonal," (3) "much," "wnphaaitwl," or "spedal attention."
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FSYcaouoor in nokmal schools
time by bringing together in another place (Table 4) the min-
imal and the maximal time devoted to the several topics, in so
far as this is revealed by the data of Table 3.'
Table 3.
DufrtfrvliM of Time to Various Topics in Fsycliology, by Itumbtr of InttiHiUoiu.
1
■5-H
1
1
1
1
1
1
1
1
i
1
1
1
1
1
■
!
i
:
1
i
1
1
1
A
b
c
d
«
t
8
h
i
i
k
I
m
.
0
P
q
r
•
I
3
,
J
I
,
,
3
.,
Lessons i
3
6
5
9
S
'
3
3
,
6
J
^
3
3
]
4
3
'
3
4
3
4
3
t
4
'
^
*
»
^
^
"
'
3
3
•
'
'
,
,
6
7
7
6
7
4
6
u
9
10
7
,
J
I
4
3
»
3
8
8
8
'3
8
9
9
5
5
7
9
'3
I
I
I
3
I
I
4
3
I
2
I
3
1
S
4
1
1
t
4
3
3
»
*
3
>
'
Weds
6
9
»4
■
■
I
VeryUttk....
S
8
4
,
,
3
3
S
3
,
1
,
,
4
4
10
6
Some.
4
4
1
a
6
'
'
3
9
S
3
7
"
4
S
S
3
6
6
'
■This divergence in emphasis of different pluses of psydiology io the normal school
msy be further illustrated by the following examples of questions selected from num-
erous ezamination papas submitted with the replies to the questionary. An inqtec-
tion of these questions will convince the reader that the instruction in the schools con-
cerned is sometimes too technical, sometimes too diSuse, and that it often exacts on
the part of the piqiih ability to answer questions that scarcely confonn to a sdentlfic
standard.
I. On what docs the value of a school eierdse depend?
3. Why is he who is no longer a student unfit to lead others?
3. Name lo standpoints from which one may study the stream of thought.
DiBiiizcdb, Google
GBf MONTSOSB WBIPFLS
Minimal and Maximol Amovnti of Time DaeUi to Important Topia in Ikt Cenrst n
Psydulogy.
Topic.
(a) Sdentificmethodi
(b) Quaai-philoMiplucal probtani
(c) Central nervous system
(d) Sensation and the sense-oigans.
<c) Attention and iotcRat
(f) Afiection, feeling, and emotion
(g) Reflexes and instincts
(h) Learning, habit, educative processes
(i) Action and volition
(j) Association
(k) Perception and observation
(1) Memoiy
(m) Imagination
(q) Conception, judging, reasoning
(o) Mental development, heredity, child-study
and adolescence
(p) Individual differences
(q) Animal psychology
(r) Hypnotism, sleep, dreams, etc
(s) Hygieneoftbesenses, fatigue, etc
HinlmilTImt. MutatlTI
I Lesson
aLessons
3 Lessons
4PeTiodi
jWe^
9We^
9 Weeks
3Weeb
3We^
3 Weeks
6 Weeks
4 Weeks
jWe^
4We^
3 Weeks
>We^
4 Weeks
i4Wedks
sWe^
SWeAs
3 Weeks
4 Weeks
eof th«
5. Analyze water in teims o( the Atomic theory.
6. Distinguish between sensations and associations.
7. Name 10 differences in pitch.
8. Is an educated man always a good man?
g. Outline imagination as in class.
10. Recall thewdght of your books on your arm: contrast and con^wietbewd^t
of the inner order with that of the outer otder.
J I . Give in full the principles of a system of education that is the logical outcome of
psychology.
11. Name 50 instincts, localizing each loosely in its period.
13. What is right, good, wrong, evil, and what drives us to do right?
14. Define materialism, personal identity, intuition, synlhem, enthymeme.
15. Name 10 recognized psychologists; mention some of their writings and state their
general position in the field of psychology.
16. Is space subjective or objective? Give your reasons for our answer.
17 Discuss the validity of the conclusions readied by experimental psyduJogy.
18. Arrange a program of studies for children from three to sixteen that shaU be in
harmony with genetic psychology.
19. Explain the psychologic basis of "I think, therefore I am."
30. What is meant by intuitive knowledge? Give three classes of intuitions.
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FsrcBOLOcr m normal schools ai
E. METHOD OF CONDUCTING THE WORK IN PSYCHOLOGY.
Question 10. Use of the text-book. Of 73 replies, 67
asserted that the text-book was the chief feature of the work,
i.e., the text supplied the essential information, formed the
basis of recitations, discussions, etc. In 6 other schools, the
text-book is the main feature of the course, but there are con-
siderable departures into fields not therein presented. In 7
institutions, the work emphatically does not center about a
text-book, but consists in a discussion of the experiences of
the students and of their observations of the behavior of
children. In some of these institutions a text-book is
employed, but more than half of the time of the class is
occupied with discussions, outside reading, and lectures by
the teacher.
As an example of work which is but little confined to a text, I may refer
to the extended report submitted by Prof. Frank Manny of Kalamazoo,
Michigan, in the course^of which he says: "In the introductory courses,
the problem in each case is to learn to read the text and similar material
in the library with intelligence." A handbook is issued which serves the
pupils as an aid in selecting material. "We aim to introduce students
to some of the literature and materials with which they need acquaint-
ance for work in classrooms, teachers' meetings, private study, etc."
About one-fourth of the time is given to "very exact ' reaction- work, '
such as five or ten minutes writing on a prepared or unprepared topic,
furly extended individual recitation with a view to test ability to ' think
through' and organize a definite section in its larger relations. This
frees the rest of the time for more informal discussion and coofetence.
Informal lectures take probably another fourth of the time. A physician
came in and gave demonstrations on the human brain. Some simple
experimentation is done along the lines suggested by Thomdike, Judd,
Witmer, and Seashore."
Question 15. Studying in the class. In one institution
nearly all the studying done by the pupils is actually carried
on during the periods that the class meets: in 8 institutions
the class hour is either often used entirely for studying or a
portion of it is regularly so used: in 15 institutions the class
period is occasionally used as a study period, e.g., during the
first few days or at other times when the work is difiicult or
during the discussion of the assignment for the following
lesson: in the majority of institutions (66), however, all
studying is done outside of the meeting period of the class.
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39 cur MOHTKOSE WBIPPLB
Question 16. Use of lectures. Of 73 teachers who give
lectures in the classroom, 14 confine these lectures to an expo-
sition of the material of the text-book; 25 lecture only on
topics not treated in the text; 34 lecture both on the text-
book and on outside topics.
Question 19. Lectures by non-faculty members. No normal
school reports a regular system of public lectures by 'outside'
talent. In one school there are frequent, in 36 occasional
lectures on psychological matters by visiting authorities.
Question 11. Devices of method. The compilation of the
replies concerning the plans used to present psychology offers
somewhat the same difficulty that was encountered in Ques-
tion 31 (distribution of time to topics), although the replies
are more numerous and the generalizations are correspond-
ingly more reliable.
Table 5 summarizes the results, by number of institutions,
in three groups, according as the replies were given in descrip-
tive, absolute, or relative terms. For convenience, the chief
points of interest in this Table are here restated in verbal
form.
(o) Lectures by the teacher. The most common proportion
of time expended in lectures is one-fifth. Most normal-
school teachers of psychology make occasional use of lectures,
but it is not usual to devote as much as one-half of the time
to them. The single institution in which lectures are given
daily is that at Danbury, Connecticut, where but 22 hours
in all are given to psychology. Most of the lectures reported
as 'occasional' are of an informal nature and restricted to
portions of the subject-matter that offer particular difficulty.
(ft) Demonstrations by the teacher. These exercises are, as
a rule, used but seldom in the normal-school course. Pre-
sumably 5 minutes per day would cover the time thus expended
in the average institution. In so far as reported,
the demonstrations appear to be confined almost wholly to
the anatomy and physiology of the brain or of the special
senses, and only infrequently serve to illustrate more strictly
psychological principles.' It is probably fair to assume that
'See also under queadon 13, in Section F. below.
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rsrcBOLOCT in nokual scaoots
Tabu s-
Frtfuaicy 0} EmploymaU o/Diftrent Uahodt oJPrumtmt Piychology
I!
11
Seldom. .
Some —
Much...
laMonth..
laWeek...
saWeek...
3«Week...
Daily
A
A
■h
most of the 50 teachers that did not reply to this F>oint do not
use any form of class demonstration.
(c) Experiments by students. As 43 teachers do not reply
to this point, and as 43 of the 57 who do reply report either
merely 'yes' or 'seldom,' it is obvious that, unless a special
course is given in exiierimental work, or a special period is
set apart for it weekly, the normal-school student of psy-
chology does little or no experimental work.
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14 GVr MOKTROSE WBIPFLS
The following compilation of the subject-matter of these
student experiments shows that most instructors do not use
a regular laboratory manual, but pick up a few simple experi-
ments from texts like Witmer or Titchener's Primer of Psy'
chology, and that the work is confined for the most part to
sensation (especially the eye, ear, and skin) and to association,
memory, and reaction-time.
SUBJECT-MATXEE OF S3£PEBI1CENTS, BY NXniBER OF mSTITUnONS.
DeaUtif vilk setuatum Mid ftrception Dealing mlh ellur Tapiet
Sensation (not specified) 4 Attention i
Tests of the senses 3 Reaction-time i
Training of the senses. i Association 5
Visual sensation 3 Memory 9
Optical illusions 5 Imagery i
Colormixture i Halut i
After-images i Fatigue. .
Color Vision i
Temperature 3
Esthesiometiy i
Weber's law i
Space perc^tion 2
Localization of sound. i
Suggestions for this work are derived from Judd (2), San-
ford (l), Scripture (i), Seashore (4), Titchener (5), Witmer
(7).
(d) Class discussions. The practise of holding class dis-
cussions of text or lecture is observed in a large proportion of
normal schools, and in many cases such discussions occupy a
large share, one-half or more, of the daily recitation period.
This practise has, of course, both advantages and disadvan-
t^;es, chief among the latter being the waste of time, — at
least the waste of time from the point of view of the exposition
of a system of psychology.
(e) Dictation. It is to be inferred from the data at hand
that in 69 of the 100 schools listed, no use is made of formal
dictation by the teacher to pupil. In the 24 schools where
occasional dictation is reported, the material thus presented
appears to be outiines or summaries. Some 5 institutions
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rsTCBOiocr in nosual schools 15
indulge in what is undoubtedly an undesirable use of this
form of instruction. In one school, indeed, the work in psy-
chology consists substantially in the dictation from day to
day of the substance of a text-book on psychology.
(J) Written exercises. The normal schools make much
use of written exercises in the form of topic-reviews, themes,
tests, answers to questions in the text, or individual reports
of various kinds. A frequently reported plan is to have some
form of written exercise at the conclusion of each main topic
in the course.
(g) Introspective exercises. A few schools give their pupils
training in introspection in connection with experimental
work: a few have regular introspective exercises; the lai^r
number make but rare or semi-occasional use of introspective
exercises. The statement of one teacher : ' ' We give just enough
to get the method " is so typical of many statements that one
has the impression that the value of introspective work as a
constant accompanimentof the coursein psychology is not prop-
erly recognized by many normal-schopl teachera. Introspec-
tion is looked upon as something to be defined or understood,
or even to be tried once and then dropped. It does not ap-
pear always to be understood that to teach psychology one
must make the student psychologize.
(A) Exercises in observation. This form of work is used
with about the same frequency as individual introspective
exercises. It consists largely in some form of child-study
work, usually in reports upon the children (or upon the work
of the teachers) in the practise-school. In perhaps a fifth of
the schools this observation-work may be said to be a promi-
nent feature of the instruction in psychology: here the obser-
vation-work is extensive in scope; the data are tabulated and
often subjected later to class-discussion.
(0 Outside reading in books other than the text-book. This
kind of instruction is in almost universal use. It may take
the form of assigned references upon which written reports
are required from all students, or of individual reports from
different books on different topics, especially if the class be
large or the library small. The reading is, I judge, for the
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36 GVT MONTROSE WBIPPLS
most part in text-books, though some schools make a feature
of assigning reading in current psychological magazines or in
the monographic literature of child-study. In one institution
where no regular text is used, all of the work is based upon
such reports of outside reading. Many teachers are hampered
by a lack of library facilities: there are not enough reference
books to 'go round,' and the files of educational and psycho-
ogical magazines are scanty and incomplete. Herein, inci-
dentally, lies another reason for the hesitation of the normal-
school psychologist to embark upon research work or to
enga^ in publication.
(J) Personal appointments with students to discuss difficul-
ties. In about one-half of the normal schools the teacher of
psychology has occasional personal meetings with students.
As a rule these meetings are voluntary on the part of the
student: if otherwise, it is either the student that is likely
to fail or the advanced student with a special problem that is
summoned to an appointment.
(k) Printed lists of questions for use by students. Only 25
institutions employ this useful and time-saving device. The
lists reported range from occasional dictation or black-board
presentation of a few questions to the use of questions printed
in text-books or in training-schoo! or state examinations in
psychology. Five teachers have printed for local use fjurly
comprehensive lists of questions, with or without accompany-
ing synopses of lectures.
(0 Other devices. Methods of making the presentation
successful, other than those already discussed, are reported as
follows: — dictation of an outline of psychology in the form
of a series of questions and answers (3), note-books or out-
lines to be handed in by the students (2), arrangement of
debates on psycholt^cal or psycho-educational questions
(2), organization of a "psychological club," character study
of the pupil's self, 'slip-exercises' about every other les-
son, mimeographed directions and references for the con-
duct of simple experiments, study of charts and models,
the making of drawings and charts, blackboard schematic
drawings to represent the topics read about, much time devote
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PSYCB0L0G7 IN NOKUAL SCBOOIS 17
to definitions, lo-minute oral summary of a topic by a pupil
followed by general discussion of this summary, a weekly
report of reading accomplished bearing on the course.'
Question 12. Which device is most valuable? In 77 replies
the following preferences are indicated: class discussions (22),
observation work {13), introspective exercises (11), outside
reading (7), lectures by the teacher (5), experimental work
(4), printed outline of the course (3), and oneeach forthe
following: informal 'text-book talks,' individual and group
work with children, application of psychology in actual teach-
ing, oral recitations, demonstrations by the teacher, personal
appointments, questions by the inductive method, "enlarge
(?) drawings of the brain," blackboard digrams of psycho-
logical principles, collection of charts, analysis of concrete
instances of conduct, "use of the text through personal expo-
ation."
F. THE USE OF EXPERIHENTAL, OR LABORATORY WORK IN
THE NORMAL SCHOOL.
Question 3. Courses in experimental psychology. Only 4
institutions report a regular course in experimental psychology
viz: Duluth, Minn.; Cedar Falls, Iowa; Emporia, Kansas;
and Greeley, Col. Duluth, in fact, ofTers two courses: those
at Emporia and Greeley are more on the order of experimental
pedi^ogy than of regular experimental psychology.
In a number of schools circumstances are such that a for-
mal course in experimental work is out of the question, yet a
'TliiB device lepDrtedfromaMichiguiidiool, deserves &short explanation. I quote
u follows: "Onedevicegivea very utisl&ctory results: it is c&lled the "Weekly Com-
munication" and is due each Monday. The requirement is simple and does not need
. to take more than five minutes. It is that the student list any reading he has done
during the week that has bearing upon the course he is taking. Many students very
soon come to extend this to cover practically all their reading and also to mention lec-
tures, sermons, concerts, observations, etc. In many cases comment is nude and
questions asked which lead to real communication. Where the matter is too involved
for writing, there is a conference at office bouts, or at my home, or on Friday afternoon
tramps in the case of the boys. The time given to reading these 'communications'
is a real pleasure and it always brings to n^ notice material of value which otherwise
would have esc^»ed me."
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38 GUr UONTSOSB WHIPPLE
considerable amount of this work is incorporated in the
courses in general or educational psychol(^y.
Question 4. The laboratory equipment.
(a) Is there a psychological laboratory? Fiveof looschools
reply in the affirmative, but only 3 (Los Angeles, Greeley.and
the Brooklyn Training School) seem to have an equipment
worthy of the name.
(b) Any collection of psychological apparatus. Although
33 schools report collections of apparatus (not targe enough or
sufficently organized to term a laboratory), these collections
are for the most part but scanty and are not strictly psycho-
logical in character, but comprised of models, charts, and
lantern slides illustrative of the central nervous system or of
the sense-ot^ns.
(c) Its value. From 26 replies, it ts found that the average
value of the laboratory or collection of material is $215, the
maximal value $1000 (Brooklyn Training School), the mini-
mal value about $25. The laboratory at Greeley isappraised
at $500, that at Los Angeles at $300.
(rf) When established or collected. The oldest 'laboratory*
dates from 1893 (purchase of $500 worth of apparatus by the
Keystone Normal School, Kutztown, Pa.) : all the others date
since 1903. Three institutions are starting laboratories dur-
ing the present year (1908-9). It may be recalled in this
connection that a lai^ number of teachers desire to institute
laboratory work in the normal schools as soon as local condi-
tions will permit (Question 32).
(e) Yearly appropriation. Only 5 replies were received:
three stated that appropriations could be secured to meet the
teacher's demands from time to time. The Albany State
Normal School will soon have a yearly appropriation, though
the amount is not yet known. The Central State Normal
School, Mt. Pleasant, Michigan, is the only institution in
our list of 100 that enjoys a yearly appropriation ($250) for
the equipment of a psychological or psycho-educational
laboratory.
(/) Housing of the collection of apparatus. From 15
answers, we learn that 7 schools have a separate room given
over to work in psychology, while in the remaining 8 the
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PSrCBOLOGT IS NOKMAL SCBOOLS 39
psychological apparatus is housed in rooms devoted to other
laboratory work, usually to physics or biolc^y. In a number
of schools the modest equipment of charts or brain models is
tucked away somewhere in a recitation-room, while several
teachers regret that what little material they possess is not
available for want of room.
Qnestion 13. Demonstraiions of an experimental character
given in class. The frequency of the use of demonstrations
is shown in the following list:
m-time 6
Memory 5
Tests of assodatiOQ 4
Central nervous system 4
Optical illusions 3
Fatigue 3
Colormlxture a
Range of attention 2
Duration of attention 2
Auditory localizatioD 2
Perception 3
Apperception 2
Feeling-tone 2
The list, it will be noted, bears a close resemblance to that
of the experiments performed by students (Question ll, c).
Question 14. Apparatus deemed especially useful for demon-
strations. The order here naturally reflects in large measure
the preferences of the preceding list.
Use of kymograph.
Field of vision
Dermal sensation
Sense training
Color sense tests
Test3 of senses
Tests of discrimination . .
Motor sense
Weber-slaw
\^ual perception
Reflex action
Thought processes . .
Colored papers...
Electric motor...
Esthesiometer
GaltoD whistle
Ophthalmotrope . .
Prisms
Sphygomgraph. . .
Spirometer
Reaction-time a[q>aratus> 8
Colormizer , 6
Ei^ograph 4
Charts 4
Tuning forks 4
Brain models 4
Kymograph 3
Pseudc^tics 3
Set of lantern slides 2
Drop-screen apparatus a
Test-weights a
Tambours 2
Monochord 2
Autoharp i
Audiometer i
' Usually Sanford's Vemiei chroooscc^, although one school boasts a Hipp.
Resonators
Tapper'
' Time of movement apparatus' .
'Testofattraition'
Witmer's test material
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CUT MONTKOSE WBIPPLB
CONCLUSIONS AND SUGGESTIONS.
1. The normal school as an institution differs in so many
respects {requirements for entrance, age of pupils, length of
course, professional aim, etc.) from the college or university
that the teaching of psychology in the one differs, and in all
probability must differ, from its teaching in the other. It
follows that what proves to be best for the college course in
psychott^^ is not necessarily best for the normal-school
course in psychology.'
2. It would undoubtedly be advantageous to arrange
conferences among those who are interested in normal-school
psychology, for the interchange of views and for the discussion
of the problems suggested by this Report. I should, there-
fore, recommend that this Association appoint a Committee
to draw up an advisory syllabus of subject-matter, to supply
lists of references, to outline suitable experiments and demon-
strations, and, in general, to standardize, so far as may prove
feasible, the normal-school course in psycholc^.
3. The teacher of normal-school psychology should have
received at least three years of special graduate training in one
or more universities. This training should be such as is
required for the doctor's degree, and should include a thorough
acquaintance with laboratory methods. The study of the
science of education should have received a d^ree of atten-
tion at least equal to that required for a minor subject for
the doctorate, and the teacher should have paid special
regard to the points of contact between these two subjects.
4. It is desirable that the normal-school teacher of psy-
chology confine his work to that field. If circumstances com-
pel him to teach other subjects, it is best that these subjects
be those closely correlated with psychology in the work of
the institution, viz: general and special methods, school
hygiene, child-study, the principles of education, observa-
tion and practise-teaching. These are, in fact, the combina-
' The writer keenly appreciates these differeocea, and hai had no penonal experience
in nontul-Khool leaching. Hence the propoaitlona that follow are offered with no
thought of authotitativeness, but solely with the idea that they may serve as a provift.
ional basis for discussion.
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PSYCBOWCr IK HOKMAL SCHOOLS 31
tions most commonly found. Biology and physiology, and
perhaps to a less extent, ethics and logic, if these are taught.
may also be regarded as natural concurrent lines of work in
the small school with few teachers.
5. Given the preparation described in Proposition 3, the
normal-school teacher of psychology should have his work so
arranged that he secures the time and the energy required for
productive original work. This point is urged from the con-
viction that, although the normal school is essentially a
training school and is conducted for the immediate benefit
of its students, nevertheless, many capable teachers of psy-
chology can undertake original work with consequent increase
of their teaching efficiency and with advant^e to the cause
of learning, and from the further conviction that, if normal-
school teaching is to offer nothing but routine class work, the
better class of college and university graduates will never
look to these institutions for a permanent career.
6. The teaching of psychology in the normal school un-
questionably presents difficttlties that are greater than those
met with in the college. This condition follows (i) from the
immaturity and me^er general information of the average
student, (2) from the short time available for the entire course,
and (3) from the constant pressure to make everything simple
and immediately practical. To meet the first difficulty the
normal school should require a four-year high-school course
as a prerequisite for admission: to meet the second, it should
rearrange or extend its own curriculum : the third would be
partially avoided by these two modifications; it may be fur-
ther met by securing teachers who know enough pisychology
to adapt it to the situation. Just now, in not a few normal
schools, lack of preparation of the teacher is probably as
evident as lack of preparation of the student.
7. In schools offering more than a two-year course, it
would probably be found advantageous to give to first-year
students a brief, elementary, and introductory course in psy-
chology designed for general orientation, and to give one or
more advanced, systematic courses to the same students in
the last year.
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3» cur UOSTROSB WBIPPLS
8. In the normal school it is not necessary, and probably
on the whole it is not desirable, to separate general and educa-
tional psychology.
9. There is no need in the normal school for courses, either
required or elective, in physiological or in abnormal psychology.
10. Psychology should be taken up either before, or
together with, courses in the principles of education, child-
study, and exercises in observation or practise-teaching, and
the study of special methods of teaching the several studies.
A course in 'general method' would appear to be quite un-
necessary if the educational psychology has been properly
taught.
1 1 . The average time given to psychology in normal schools,
90 actual hours, is sufficient, if properly utilized, for the pre-
sentation of a sound course in psychology, general and educa-
tional. If elective or advanced courses are to be introduced,
more than 90 hours are needed.
12. Classes numbering more than 50 students ought to
meet in two or more sections, and no one of these should
exceed 30 to 35 students, if the best work is to be accomplished.
13. The general aim or purpose of normal-school psychol-
ogy is phrased in much the same way by the majority of
teachers, who seek to impart such an acquaintance with
mental operations as shall contribute to the success of the
graduate in his professional work. But, as a matter of fact,
this statement of the aim is not definite enough to determine
the actual content and method of presentation of the course.
The aim as thus stated might, for example, be interpreted
to mean that a number of isolated facts or principles should be
selected from psychology and applied to the art of teaching;
or, to mean that examples of educational procedure should
be analyzed in the effort to work back to the psychological
principles involved in them ; or, again, to mean that the course
should be conducted in such a way as to develop a 'point of
view' in the student's mind. For myself, I am convinced
that the first aim must be to familiarize the student with his
own mental processes: only when he has thus learned to
' psychol<^ze' can he be taught to see the application of
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rsrcBOWGT in normal schools 33
psychology in the classroom. And I am convinced, further-
more, that the preliminary appreciation of the ' lawful' charac-
ter of mind which the first aim implies can be gained best
through the presentation of psychological principles in a
systematic manner. The first aim is, therefore, to secure
real assimilation of a system of psychology: the second aim
is to develop skill in observing and in interpreting the mental
phenomena of daily life in terms of this assimilated knowledge.
14. The present report sheds little light upon the success
achieved in normal-school psychology, save that it reveals a
consensus of opinion on the part of the teachers of psychology
that the general aim just mentioned is attained. An investi-
gating committee might conceivably find it worth while to
collect evidence from normal-school graduates in the field
as to the manner and d^ree in which psychology has benefited
them.
15. In studying the distribution of time to the subject-
matter of psychology, we find that there is scarcely any topic
or phase of psychology that does not seem to receive relatively
too much attention in some normal schools and too little in
others. But it is probably more nearly true of psychology
than of any other normal-school subject that no two teachers
or text-book writers would agree upon the distribution of time
and emphasis. The writer's own judgment would be some-
what as follows: (i) that special consideration should be given
to instinct, attention and interest, habit, the process of learn-
ing, associative and organizing activities, including memory,
concept-forming, judging (apperception), (2) that a moderate
amount of consideration should be given to sensation and the
sense-organs, the general organization and operation of the
nervous system, the psychology of action, and the psychology
of individual diflerences (with reference to the inheritance of
capacities), and (3) that only occasional or brief reference
should be made to philosophical problems, affection, feeling,
emotion, reflex action, space-perception, animal psychology,
sleep, dreams, hypnotism, fatigue, and mental hygiene.
But any such advisory list, unsupported by reasons, must
of necessity appear personal and arbitrary. Again, it is to
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34 cor UOHTMOSE WaiFPLX
be noted that the very idea of classifying and 'pigeon-holing'
mental experience is repugnant to some teachers, who, either
because the notion of a 'system' implies for them something
formal, 'cut-and-dried,' and arbitrary, or because mental life
impresses them as being essentially unitary, prefer to study
behavior in wholes, directly, and in concrete situations, or
at least to avoid what they term the disjecta membra (sensa-
tion, imagination, memory, etc.) of the psychological texts.
I have already expressed my conviction that the use of a system is
essential in the teaching of psycholt^y, if the best results are to be secured.
Insupportof this position, it may be said: (i) that practically every ade-
?UBte text-book is cast in the fomi, and uses the terminology of a system;
2) that it is impossible for a teacher who knows psychology not to think
this psychology in terms of a system; (3) that a system is of the highest
value to the student in enabling him to comprehend and especially to
relate and organize his observations and information; (4) that an intdli-
gent student will inevitably organize his information into some system,
and this system will almost inevitably be inadequate and incorrect if
he is left to his own devices; (5) that a system serves to reveal the 'gaps'
in our knowledge; it is worth while 'knowing what we don't know;' (6)
that the sp>edal objection to system in psychology (that the several dass-
ificatory terms are interpreted by the student as entities and as isolated
elements of mind, so that his whole notion of mental life is distorted and
erroneous),isanobjectionthatmust, and may be met by careful instruc-
tion on the part of the teacher. It is quite possible, for instance, to avoid
the " maelstrom of faculty psychology," as one writer phrases it, if mem-
ory, imagination, perception, etc., are treated as typical ways in wbidi
mind may be found at work, and if the inter-relations of these and other
types of actimty are frequendy and deariy set forth, — if, for exaxajAe,
'memory' is shown to be a name for a type of mental attitude or activity
that is already familiar to the student through his study of organic plas-
ticity, retention, habit, associative tendencies, 'centrally-ezdted sensa-
tions,' etc.
16. Every normal school should offer a specific course in
school hygiene. The testing of the senses for practical pur-
poses, the hygiene of study, fatigue, and allied topics should
be placed in this course.
17. While, for normal-school use, some future text-book
may improve upon those now in the market, many teachers
apparendy fail to select the best texts now available, or to use
them with skill when they are selected. Again, it may as
well be admitted that, for some students, psychology is intrin-
sically difficult, and that psychology is necessarily more com-
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PSrcaOlOGT IK KOKMAL SCEOOLS 35
plex than other normal-school subjects, so that any text-book
that treats the subject adequately will be difficult for these
students.
1 8. Less reliance should be placed upon the text-book and
more upon the teacher's expository talks or lectures than is
at present the custom in the typical normal school. This
procedure will render the text-book less of a stumbling-block
than it seems now to be, and will enable the students to make
more rapid progress: it will thus save some of the time that
many teachers find insufficient.
19. It should be possible in any ordinary institution to
arrange that aii studying he done outside the classroom.
20. The normal-school teacher should enrich his course
by the introduction of more demonstration-experiments, espec-
ially demonstrations of the more strictly psychological princi-
ples. The Committee contemplated in Proposition 2 might
profitably collect or prepare a list of recommended demon-
strations.
21. Class-discussions should be carefully directed, and
probably less freely employed than is now the custom. These
exercises are not an end in themselves, but a means of teach-
ing psychology. To stimulate the active interest of imma-
ture students and to detect and avoid misunderstandings of
the text-book, they have unquestioned value, but, in ped^ogy
as elsewhere, there can be " too much of a good thing. " Who
has not seen 'class-discussions' degenerate into aimless anec*
dote or blind dispute over topics that might have been pre-
sented by the teacher in a few minutes of clean-cut exposition,
to the gain of the pupils in intelligent grasp of the points at
issuei* Normal-school teachers who find the time too short
to teach psychology may well consider whether a portion of
the time that they now devote to class-discussion might not
be employed more profitably in other and more direct methods
of instruction.'
' To Uke an curarae illusUatirm, I heard recently of a young teftcber who was m
impieased with Uie virtues of the inductive method that he used this mode of procedure
almost exclusively in his dais in psychology, with the result that at the end of the tenn
the dass had coiiq)leted the survey of the field of sensation. This daw even hdd,
'discussiom' of the itructuie of the central oervous system.
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36 CVr IfONTROSB WHIPPLB
22. Format dictation is out of place in normal-school psy-
chology, save for occasional and special purposes, e.g., the
dictation of a few important definitions, of summaries, etc.
22. Exercises demanding introspection are of fundamental
value in any course in general or educational psychology.
The normal-school teacher, like the college instructor, must
lead his pupils to 'psychologize,' to the end that the mental
operations of which psycholc^y treats shall be realities and
not mere empty verbal assertions.' The formulation of a
series of introspective exercises should receive careful and
intelligent consideration by the teacher. Suggestions are to
be found in many texts . The Committee already mentioned
might again be of assistance in this connection.
24. Observation-work is of special value in making the
operation of the salient principles of educational psychology
visible to the normal-school student. If the work be properly
articulated, courses in psychology and in special method ought
to play into one another's hands through the medium of
observation and practise-teaching. If observation-work can
be arranged concomitant with the work in psycholt^;y, so
much the better, but, even so, the value of the observation
will be largely lost if it is not both systematized and super-
vised by the teacher of psychology: the novice in psychology
fails to see psychology in application until he is told where to
look.*
25. The assignment of outside reading is another device of
value; but this, too, demands careful supervision. The diffi-
culties are evident: students dislike to read the same thing in
several different books; still more do they dislike to read
apparently conflicting statements or to encounter unfamiliar
terminology. If written reports are demanded, these take
' It U the writer's experience that it is always the studeot who cannot, or will not
get the introspective habit, who falls back upon the verbal reproductiou of text <m lec-
ture-mateiial as the real content of the course, and that it is nearly always this student
who finds psychology " too abstract," and who runs perilously near, if not over, the
danger-mark in the final examination.
* The writer has found, for example, that the use of a printed " Guide to Observa-
tion" very greatly increases the value to college students of the ao-hours of hi^-sdiool
observation required for the New York State College Graduate Certificate.
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rsrcaoLOGT in nohmal schools ^j
much time both from student and teacher: if they are not
demanded, the reading is lilcely to be hurried and thus to be
of little permanent value. Again, if the class be large and
the assignments numerous, the library is taxed to supply
numerous copies of certain books and may thus be unable to
purchase others that are much needed. Many students, in
our experience, have almost literally to be taught to read
intelligently. Yet, as the reports show, outside reading is,
on the whole, a valued and a valuable adjunct: it helps par-
ticularly to overcome the limitations felt to inhere in the
'single text-book' plan.
26. If lectures are given, as we think they should be, they
may be profitably accompanied by a printed or mimeographed
outline or syllabus, This plan helps the student to follow the
lectures (or to read the texts) intelligently, gives him a
general perspective of the course, and compels the instructor
to arrange his material in orderly fashion.
27. Whether or not lectures are given, the assimilation of
the work in psychology will be distinctly facilitated by the
use of lists of questions, preferably printed andsupplied to each
student. These questions must, in the main, avoid a form
that admits of answer by direct reference to the text-book,
and should seek, rather, to develop introspection, observation
and thought: in short, they should test the student's ability
to apply his psychology.*
28. The oral recitation of the examining type (quiz on the
text) is probably a necessary feature of normal-school work,
but the teacher should not employ it further than conditions
demand. Like class discussions, it may be made a fetich. It
is a time-consuming operation, more needed in instruction on
the public-school than on the professional level. The reci-
tation when used for development-work has, of course, greater
value, expedally in the hands of a skillful teacher.
'Iflnuiybe permitted ODce more to refer to my peraonaJ experience, I may itatethit
I have found a printed list of questicHis, when properly HamifiBd and supplied with
references to a number of teiU, to be of great assistance to college students in chccUng
op their progress in psychology. Such a quis-list is equally useful for review or for
■dvanod assignment: in dther case it guides the student in his study, ^ows him what
he should know, and compels his active thought and attention.
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38 cur MONTKOSB WHIPPLE
29. In general, the normal-school teacher, owing to the
conditions under which he works, must search for, and use as
skillfully as he may, all the devices of presentation that can
further his aims. Notebooks, personal appointments, debates,
psychological clubs, charts, diagrams, etc., are schemes that
will occur to all teachers. It would be absurd to attempt to
prescribe in detail which of these aids should be used, andto
what extent, since it is a matter of common observation that
every teacher works best by the methods that he himself
devises, or in which he himself most thoroughly believes, and
that a skillful teacher often achieves His success by a method
that a poor teacher employs in vain.
30. The problem of the introduction of experimental psy^
chology, or of laboratory courses, is the most perplexing one
that confronts the normal-school teacher. Various reasons
may be adduced for the introduction of such courses : the seven
that follow are, of course, not exhaustive or mutually exclusive :
(i) to illuminate and illustrate the subject-matter of the gen-
eral course in psychology, (2) to add a certain attractiveness
to the work in psychology, (3) to make cleju^er to students the
methods by which modem psychology has been elaborated, (4)
to give training in scientific procedure and acquaintance with
the spirit and method of experimental investigation in science,
(5) to train a limited number of advanced students to parti-
cipate in minor pieces of research work in the institution, (6)
to prepare students to appreciate and to participate in experi-
mental pedagogy (as distinct from experimental psycholc^y),
(7) to train students in making examinations and tests of
children in the classroom (particularly various forms of mental
and physical tests, diagnostic of retardation, sensory handicap,
etc.)
We have seen that, as matters stand, experimental psychol-
ogy is not a feature of the typical normal-school curriculum,
but that a considerable number of teachers wish to incor-
porate such work. It does not appear, however, that serious
attention has been paid by many of these teachers to the
reasons for this introduction, since the experiments that are
already in use appear to have been selected, not so much
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FsrcaoLocr in horual schools 39
because they bear upon educational psychology, as because
they are stock experiments in the psychological laboratory.
I yield to no one in my love for research work in psychology,
in my belief that a drill-course in experimental psychology
has lai^ possibilities of culture-value, or in my conviction
that the experimental method must be applied to educational
problems before these can be solved, but I do not on this
account believe that every kind of experimental work in
psychology that is given in college classes can be offered with
equal success or justification in the normal school. I see no
reason, for example, why every prospective teacher should
work out the constants for Weber's Law, or investigate the
localization of sound, or try to measure fatigue on the ergo-
graph, although these are perfectly legitimate and regular
features of experimentation in the college laboratory.
For these reasons it seems to me that the present experimental work in
the nomial schools shows faulty perspective. Take, for example, two of
the most used demonstration-experimenta — the ergograph and the reac-
tion-time test. These have the merit of being 'showy,' but it would be
hard to select another pair of experiments that would be more complex
and 'tricky' in their real meaning and interpretation. On the other hand,
the centr^ feature of educational psychology, — assuredly the process of
learning — is not mentioned specifically in the list of demonstrations,
althou^ it may be covered in part by experiments in memory or apper-
ception. Again, the demonstration of reliable tests of vision and hearing
— ^tests wbidi, in the absence of special courses in hygiene, demand treat-
ment as a phase of ' mental hygiene' in the normal-s(£ool course — is men-
tioned in the list of but a single institution.
I contend (i) that the teacher of psychology should be
drilled in laboratory methods and practice, and that he
should endeavor to keep himself informed of the progress of
experimental psychology at large, (2) that a selected number
of experiments, mainly illustrative of the more important
principles of mental elaboration, should be presented to
students in the general course in psycholc^y at a special period
and in a special room set apart for the purpose, (3) that in
institutions offering more than a two-year course, a more
systematic course in experimental work including, the solu-
tion of simple psycho-educational problems, should be given
as an elective to advanced students, and (4) that those stu-
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40 CUT UONTMOSK WBIPPLS
dents who display exceptional ability in experimental work
should be encouraged to seek further instruction in depart-
ments of psychology and education in the university.
31. In the absence of any exercise-book or ffianua/ specially
prepared to guide experimental work in normal schools, the
teacher must adopt an eclectic plan. The laboratory and
library should, accordingly, be supplied with copies of all the
texts in experimental psycholc^y. That normal-school teach-
ers would welcome suggestions as to the best selection of
experimental problems has already been pointed out.
32. The equipment of the normal-school laboratory for the
prosecution of such work as has just been proposed need not of
necessity be expensive. For an original outlay of from $200
to $750 the beginning of an experimental course canbesecured:
for maintenance and further extension a yearly appropriation
of $50 to $100 would, perhaps, suffice.'
' The practical working out of the piindples of general laboratory economy, like
the successful application of methodi of instruction, hinges in the last resort upon the
teacher. A sldUed psychologist can give an instructive danonstiatioii with such homely
materials as colored paper, strings, scissors, and cardboard, when the neophyte would
be helpless without his kymograph, his electric motor, and his other "brais-ware."
This is not to be construed, however, to discourage elaborate equipment, or to applaud
a policy of parsimony on the part of normal-school authorities. The skilled piycholo-
gist welcomes a good color-mixer, too.
If advanced or original work b attempted, then, of course, instruments ol predaion
become imperative. In working up an nlucational laboratory for research and demon-
stration-work at Cornell University, a]^>roziniatdy $1000 baa been invested during
the past eight years, while the yearly maintenance appropriation averagei about $ioo.
An inventory of this equipment will be published in the Jottmal of Eiueaiioiial
PtycMogy mthin a few months in the hope that it may ofier some auggestiona to
those who are develt^ing experimental work in the normal school.
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THE TEACHING OF ELEMENTARY PSYCHOLOGY
IN COLLEGES SUPPOSED TO HAVE NO LAB-
ORATORY.
By Mary Whiton Calkins.
WdUsUy CaUttt.
The first part of the report herewith submitted summarizes
the replies to a questionary sent out to 80 colleges and uni-
versities. Replies complete enough for use were received
from 47 institutions.' It appears from these statements
that the elementary course as given in the aver;^ college is
usually a required course, more often running less than a year,
and often, though not always, meeting in large divisions.
The course tends to be taken mainly by juniors but in con-
siderable number also by seniors on the one hand and by
sophomores on the other. It is conducted partly by lectures
and partly by discussions or recitations. The students make
use of a text-book but their study of it is supplemented in
various ways.
The replies to the questionary are summarized in more
detail in the statements which follow ; and these are condensed
from verified tables compiled by Professor E. A. McC. Gam-
ble.* The replies concern:
■The list is the following: Amherst, Bates, Bethany, Boston, Bowdoin, Brenau,
BuUer, CtJgate, Cobrado College, Columbia College (South Carolina), Dalbou^e,
Det Moines, Dickiiuon,EImira, Fayette (Upper Iowa), Geocpa, Georgetown, Grinnell,
Haveriord, Knox, Maine, Maiietta, Mercer, Middlebury, Morningdde, College of
City of New York, New York Normal College, Oberlin, Ohio University, Penn. State,
RandoIph'UacoD, Ripon, Rocbester, Rutgers, Simmons, Swarthmoie, Tennessee, Texas,
ToroDto, Trinity, Tufts, Union, Vermont, Viiginia, Wabash, Wells, West Virginia.
* To Dr. Gamble and to Mias. S. J. Woodward, who assisted her, my warm thanks are
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ItASr WBITON CALKINS
I. Tke Academic Status of the Course (47 cases).
(a) Required, absolutely: Cases 30
Elective absolutely: Cases 11
Part of a group in which a given number of hours must be
taken: Cases 5
Prerequisite to pedagogy (which is largely elected) : Cases . . i
(i) Prerequisite to other courses in psychology: Cases 23
Not a prerequisite to such courses: Cases 6
No other courses (or no answer): Cases 18
(c) Prerequisite to all or any courses in
philosophy; Cases 29
Prerequisites to all or any courses in
education : Cases 20
Prerequisite to all or any courses in
sociology: Cases 2
Not a prerequisite: Cases 8
No answer: Cases 5
Separate Cases 34
II.
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47
///. Tke CoOete Rank of the Students in the Course {47 Cases).
The course is open
To seniors only: Cases 4
To juniors, or to seniors and juniors: Cases 33
To seniors, juniors and sophomores: Cases 10
To sophomores, or to sophomores and freshmen: Cases 6
Without restriction: Cases i
No definite answer: Cases 3
IV. The Numbers in the Course.
The couise varies in number from less than 10 (In i case only) to 301-
300 (in 2 cases). In only 4 cases (out of 38) in which courses mrniber
60 or less are the classes broken into divisions. In i case, a course num-
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COLLEGES WITHOUT LABOKATORIES
bering 300-300 is undivided. Of 13 courses numbering more than 60,
5 are divided into 5 divisions each, 4 into 2 divisions each: while one
class of 301-300 meets in 8 groups.
V. The Rank and Work of the Teacher {47 Cases).
The course is taught
By ihit president (who teaches [^osophy also) : Cases i
By a professor, teaching
P^dwrfogy only: Cases 1
Philosophy also; Cases 15
Education also: Cases 1
Both philosophy and education also: Cases 11
Miscellaneous subjects: Cases 3
(No answer concerning other subjects) 3
By an instructor teaching
Philosophy also : Cases 3
Education also: Cases 3
By one man with assistants, all teaching
Psychology only: Cases i
Philosophy also: Cases a
Other cases (and question unanswered) : Cases 5
The statements which follow are contrasted with those which precede
in that they concern not so much the academic status, student- r^k, and
numbers but the avowed aims and methods of the elementary course in
psychology. Part U of this paper takes special account of these results.
Vt. The Emphasis of the Course {40 Cases. No reply in 7 Cases).
latraspectioD
Phjraiology
Biology
Practical Applicadoiu of psychology
Philoaophy
VII. The General Method of the Course {47 Cases).
(a) Predominantly by lectures: Cases 8
Predominantly by class exercise: Cases 24
A fairly even mixture of the two methods: Cases 10
No definite answer: Cases S
(b) Recitation required (31 replies).
To a considerable extent: Cases 30
To some extent only: Cases 11
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44 V>(Jtr WBITON CALKIUS
VIII. The Method of IntrodaciKe a SiOjea U? Cosa).
By assignment of reading in textbook: Cases 35
By lecture: Cases 8
By questions demanding introspection: Cases 5
No definite answer: Cases 11
IX. Details of Method (Cases 47, not exdusive).
A textbook is used: Cases 40
Outlines are used : Cases 33
Review questions are used: Cases 19
CdlateraJ reading is assigned: Cases »S
(In 10 of these cases the extent of the reading is "considerable. ")
X. The Use of Experiment (Cases 47).
(a) Real laboratory work 7
(In 3 of these cases tJie laboratory work is "important;" in 3
others it is supplemented by out-of class eiqwrimenting.)
(d) Directed experiments outside the laboratory: Cases rS
(In 9 of th^ cases in the experimenting is "important.")
No experimental work (so far as indicated) : Cases a
(c) Use by the lecturer of
Demonstration experiments: Cases 16
Physiological material: Cases 17
If we suppose that an inquiry similar to this had been con-
ducted twenty-five years ago and if we compare its hypo-
thetical results with our own figures, the outlook will be
mainly encouraging. The course in psychol(^;y has been
pushed backward from the senior year so that a student can
apply his psychology in his further college study. The
course is no longer taught by the college president in the
intervals of administrative duty, nor as a secondary occupa-
tion by the teacher of radically different subjects; and psy-
chology has been freed from its entangling alliance with
philosophy. On alt sides, also, we find evidences ofvigorous
and individual teaching.
Our results are however, of chief importance in so far as
they make clearer and more vivid our conception of the true
aim and of the right methods of the elementary course in psy-
cholt^y. In the paragraphs which follow I have ventured to
formulate the results of my own experience and observation.
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COLLEGES WirSOVT LABORATORIES
noting at various points the relation of these suggestions to
the actual procedure already described. My recommenda*
tions have reference to the general course in psychology
regarded as introductory not only (and not chiefly) to more
advanced courses in psycholt^y, but to courses in philosophy,
in education, and in other subjects. In but one respect, I
believe, may such a course differ from that elementary course
which is planned to introduce the student to further psychol-
ogy: the more general introduction-course may run through
a semester rather than through a year. Without doubt the
full year course treats the subject more adequately. Yet
precisely because of the fundamental nature of psychology,
it forms an important member of every group of studies,
literary as well as scientific or philosophical. And in many
institutions psychology can hold this central position only
if it be ofFered as a semester course. In the opinion of the
writer, such a course can be given without prejudice to
scholarship by a teacher who keeps pace with his science, who
distinguishes essential from accidental, who systematizes his
material, and who never lowers his standards of accuracy.
■ With this introduction I offer four more or less obvious
recommendations :
I . Psychology is psychology whatever the use to be made
of it. First courses in psychology should therefore be essen-
tially the same in content and in method, whether they intro-
duce the student to advanced work in psychology or to the
different problems of pedagogy, of ethics, or of metaphysics.
the immediate purpose of every course in psychology is to
make the student expert in the study of himself: to lead him
to isolate, to analyze, to classify, and (in the scientific, not in
the metaphysical sense) to explain his own perceiving, remem-
bering, thinking, feeling, and willing. In the effort to classify
and to explain, the student will of course attack the relevant
facts of sense physiology and of bodily behavior He will
study these however as conditions and accompaniments of
consciousness. Psychology is nothing less than such a study
of selves — and primarily of one's own self — in relation to the
environment, personal and impersonal; and, conversely, any-
Digilizcd by Google
46 UAKr WaiTON CALKINS
thing more than this though it may be related to psychology,
is not psychology. If we are in earnest in the belief that
psychology is an important, indeed, an essential introduction
to the disciplines already named, we must mean by the term —
psycholc^y, and not a conglomerate of which a dilute psy-
chology is one component only. Whatever is necessary to
the study of psycholc^y for itself is necessary, therefore, to
the first course in psychology as introductory to other sub-
jects. As has appeared, this does not mean, that the two
courses need be equally long and equally detailed. In par-
ticular, laboratory experiments will probably, for reasons of
time and convenience, be barred out of the general course.
Yet it has, I think, been shown that individual experiment as
well as demonstration may advant^eously be introduced.
And, on the negative side, the utmost pains should be taken
not to encourage applications of psychology at the expense
of the psychology to be applied. The bearing of psychology
on practical problems of every day living and of pedagogy
may most advantageously be emphasized by the instructor ;
but the applications should follow upon analytic study. Not
only the purposes of scholarship but the practical aims them-
selves are thwarted by the tendency to form conclusions for
the sake of applying them.
The last par^raph has made reference to the relation of
psychology to ethics and to pedagogy. I wish to say a
special word of its relation to philosophy. In my opinion the
teacher of philosophy should connect the study, constantly,
with psychology; whereas the teacher of psychology should
exclude all discussion of metaphysical problems insisting on
the purely scientific study of consciousness. He should bar
out discussions of materialism, free will, and the like, point-
ing out that psychology is compatible with any one of the
metaphysical solutions to these problems. Only by such a
differentiation of the science of psychology from philosophy
can we rightly study the former; and only psychology rightly
studied can be of real aid to philosophy. An indirect support
to this view may be found in the answer to the questions on
dbyGOOglt.
COLLEGES WITHOUT LABORATORIES 47
the"emphasisof thefirst-yearcourse."' Of the 40 instructors
whoanswer this question, 20 lay ' predominant' or ' great' stress
on introspection and only 3 set 'tittle or no' store by it;
whereas 2 lay 'predominant' and 10 'great' stress on the
applications of psychology, and 10 pay 'little or no' attention
to the applications. Only two instructors emphasize strong-
ly the relation of psychology to philosophy as against 14 who
lay great stress on physiological explanation and biological
relation. In this connection it may be noted that the courses
of these different colleges concern themselves mainly with
the problems of general individual psychology. Only 5
devote 'considerable time' to comparative psychology; and
only 2 to abnormal psychology.
2. The second group of my conclusions is of a more general
nature. The class in psychology should not, it seems to me,
be conducted by means of 'recitations,' or 'quizzes,' and the
student should more often lake part in discussion than listen
to lecture. I think there can be little doubt that the negative
part of this statement is sound. A teacher has not the right
to spend any considerable part of the time of a class in finding
out by oral questions — "how does your author define per-
ception?" or "what are the laws of color mixture?" — whether
or not the student has done the work assigned to him. The
good student does not need the questions and is bored by the
stumbling replies which he hears; and even the poor student
does not get what he needs, which is either instruction a deux,
or else a corrected written recitation.* One is often reminded
by the conventional oral recitation of the little boy's descrip-
tion of his first day at school: "An old woman asked me how
to spell 'cat,' and I told her." Not in this futile way should
the instructor squander the short hours spent with his stu-
dents. The purpose of these hours is two-fold : first, to give
to the students such necessary information as they cannot
gain, or cannot so expediently gain, in some other way; second,
and most important, to incite them to ' psychologize' for them-
' Cf. Statement VI., (p. 43 above).
* Of 39 instructors who reply on this point to the questionary, 35 nuke use o{ this
indiqtensaUe method
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MAST WBITON CALKIHS
selves. The first of these purposes is best gained bv the
lecture, the second by guided discussion. 'Guided discus-
Mon' does not mean a reversal of the redtation-process — an
hour in which students ask questions in any order, and of any
degree of relevancy and seriousness, which the instructor
answers. On the contrary, the instructor initiates and leads
the discussion : he chooses its subject, maps out its field, putls
it back when it threatens to transgress its bounds and, from
time to time, summarizes its results. This he does, however,
with the least possible show of his hand. He puts his ques-
tion and leaves it to the student interested to answer him;
he restates the bungling answer and the confused question;
he leaves one student to answer the difficulties of another.
In a word, he takes advantage of every suKcstion, he stimu-
lates and trains his students by intelligent question and swift
reasoning, he subordinates scattered conclusions to the ad-
vancement of the discussion as a whole.
The advantage of the discussion over the lecture is, thus,
that it fosters in the student the active attitude of the thinker
in place of the passive attitude of the listener. For this
reason, in the opinion of the writer, the lecture should be
used mainly as introduction and as summing up of a subject,
not as chief method. A study of the answers to the question-
ary seems to confirm my estimate of the lecture as subsidiary
method, for less than one-fifth of those who reply to this
question (8 of 42) make predominant use of the lecture.'
The answers, however, are either non-committal or negative
as regards the far more important question of the relative
merit of 'discussion' and of recitation. It is, to be sure, not
easy to reduce the replies to common terminology, yet 20
make 'considerable' use of recitation and 1 1 more make
'some' use of it. In presenting my urgent recommendation
of the guided class discussion which is neither lecture nor reci-
tation I have, therefore, no right to claim the support of ' my
constituents.'
In this connection a comment should be made on the size
' C(. Statemeot VII (p. 69),
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COLLBCES WITBOUT LABORATOKISS 49
of classes.' Obviously it is simplest to teach large classes by
lecturing to them. Yet a spirited and relevant discussion
may be conducted in a class of a hundred or so. Of course
no more than eight or twelve, or, at most, twenty of these will
take even a small part on a given day; perhaps a half or two-
thirds will never take part; and some will remain uninterested.
But there will be many intelligent listeners as well as active
participants; and these gain more, I believe, by the give and
take of good discussion than by constant lectures however
effective.
For the benefit, however, of large classes I am convinced
that careful provision for more individual instruction should
be made. It goes without saying that students with special
questions and difficulties should be welcomed in private con-
sultation hours. Yet I think ^at more than this is needed;
and, to colleges which lack the means to establish a full pre-
ceptorial system, I recommend the division of a targe class
into small weekly divisions or conferences. Such conference
divisions may take the place of one weekly appointment of the
classasawhole;or, better, each may be treated as a laboratory
hourin addition to the regular app>ointments. The timeof the
conferences may be variously used, Students disinclined to
join in discussion in a large group will express their difficulties;
assigned questions may be answered and the answers dis-
cussed; written review papers may be returned with com-
ments ; physiological modelsand preparations may be examined
by each student of these smaller groups; and, more important
perhaps than any specific result, a personal contact may be
established between teacher and student. Obviously the
success of such a plan depends on those to whom the con-
ferences are entrusted. Able and well-trained assistants may
advantageously conduct most of them; but it will be unfor-
tunate if the main instructor of the course cannot feel the
pulse of his class by himself conducting one or two of these
conferences. And it is essential that he should give over-
sight to the conference and unity to the work, by stated meet-
> CI. Statement IV (p. 68).
.yGoo^Ie
$0 MARY WBITON CALKINS
ings with the conference-instructors and discussions of am-
ference methods. I find no evidence that this plan has as
yet been adopted. Indeed, only 5 instructors report con-
ferences with individual students (and 3 of these make only
'occasional' use of the method.) In one college, however,
a class of 60 meets in one division for lectures and in three
divisions for 'quizzes.'
3. My third conclusion is closely connected with what
precedes. It is absolutely essential thai the course in psychology
supplement text-book study by methods intended to secure the inde-
Pendent work of the student. To require of the student merely
to give back, in written or in oral form, the contents of a
text-book is to run a heavy risk of missing the bull's eye of
the course; and this, we have ever to remember, is to teach
the student a first hand study of himself as conscious. I am
not recommending that the general course in psychology be
conducted without a text-book, for I believe, on the contrary,
that precisely the beginner needs the aid of a book in focus-
ing and classifying the results of his observation and reason-
ing. But better 3 thousand times no book than a book to
be memorized. An essential means to the proper use of a
text-book is, in my opinion, to forbid or discourage its use —
and to forbear, also, to lecture on a new topic — until the
student has dealt for himself with the topic of study. Thus,
before, entering on the study of perception and ima^nation
one may direct the student to 'state in writing the difference
between perceiving a hat (or chair or vase) which isseenand
imagining a similar hat (or chair or vase) which is not in the
room. Before lecturing on the individual sense-types of
imagination the student may be required to answer, again in
writing, Galton's questionary or some one of those modelled
on it. Before reading or listening to lectures on attention, the
student may answer questions such as these: "What is the
difference between attending to the demonstration of a geo-
metrical problem and attending to the buzz of a mosquito?
What bodily marks of attention have you noticed in a dog?"
It is unnecessary to multiply examples. The essential point
is that the student be led to observe his own experience, to
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COLLSaSS WITHODT LABORATORIES 51
record his observation accurately — in a word to psychologize;
and to make the observation before, not after, discovering
from book or from lecture what answers are expected to these
questions. Individual experiments should so far as possible
be performed in like manner before the class discussion of
typical results. In all cases the results of these introspec-
tions should be recorded in writing; representative
records should be read and commented on in class; and the
discussion based on them should form the starting point for
text book study and for lecture.
The instructors who have answered the questionary evi-
dently concur in the view that a text-book is necessary: only
4 of the 47 make no use of one.' But 23 of the 40 who have
a text-book make, as I believe, a radically wrong use of it
since they introduce each topic by assigned reading in the
book. Of the remaining, 8 instructors introduce each sub-
ject by lecture and only 5 by what I hold to be the right
method — some exercise in introspection, whether simple or
experimental.
On the other hand, in almost all these college courses text-
book study is supplemented in other ways : collateral reading is
required in 28 cases, review questions are assigned by 19
instructors, experiments are performed or required in 25
cases.* All these methods have their value. Collateral read-
ing is useful first in that it protects the student from the
dogmatism or one-sidedness of his teacher or of his author or
of both ; second, in that it offers an opportunity to enlarge his
field of observation. The student is no longer a man of one
book, and can not fall into the error of regarding psychology
as a closed science. In one introductory course known to
the writer though not included in this study — that at Iowa
University — the student is required to read three psycholc^-
cal text-books besides reading and working out the experi-
ments of an experimental manual. Such a requirement ob-
viously presupposes great skill, on the instructor's part, in
the codrdination of different teachings on every topic of psy-
chology. Except in the hands of a gifted and experienced
' Cf. Sutement VHI (p. 44)-
* Cf. Sutemeot DC (p. 44).
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Sa UARV WBirOK CALKIHS
teacher the result for the b^inner in psychology might well
result in a confusion of several systems and a clear knowledge
of none. Fewer text-books, with assignment of collateral
reading on selected topics will prove, in most cases, a more
practicable plan.
The discussion of experiment in first year psychology
belongs to Professor Sanford. Yet it may here be remarked
that even a semester course in large divisions may advan-
tageously include simple experiments. These may be, in the
first place, experiments to be performed out of class and
reported. Such are experiments in visual contrast, in the
localization of temperature spots, in tactual localization.
Or the experiments may be class demonstrations — of color-
mixing, for example, or of beating tones. In using these
demonstration experiments, as in the important demonstra-
tion of physiolc^cal material (models and charts of nervous
system and of sense-organs) the important point is to keep
always in mind that the experiments are in the service of psy-
chology, that they are of use in teaching the student to classify
and explain psychic phenomena, and that they are worse than
useless if they keep him from seeing the psychological wood
for the physical and physiological trees. One of the most
interesting outcomes from the questionary is the discovery
that in 25 of the 47 cases studied, some use is made of experi-
ments.'
The third class of subsidiary methods is that of the review
questions following on lecture and reading. Nineteen (19)
instructors make use of 'review questions'. Their value as
stimulus to introspection is akin to that of the questions by
which a subject should be introduced. They should test the
student's ability to translate the formal language of his science
into concrete terms, to recognize when he meets them, experi-
ences which he can define. Several of the well-known manuals
of psychology — Titchener's "Primer," Thomdike's "Ele-
ments," Whipple's "Questions in General and Educational
Psycholt^y, " and Witmer's "Analytic Psychology" — contain
excdient questions of this type. And every good teacher can
' Cf. Statement X. (p. 70}.
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COLLSGBS WITBOVT LdBORATORIBS $3
find in his immediate surroundings the material for questions
which will lead the student to make constant applications of
his psychology.
4, The exhortation to avoid mere text-book study must
not be interpreted as a criticism of so-called systematic psy-
chology. For no science can help being systematic; and my
final recommendation, which may be very briefly stated, is
accordingly the following: Insist on clear definition, consistent
use of terms, and orderly classification of psychic facts. The
definition and classification should, of course, follow on intro-
spection; should not be accepted uncritically from instructor
or from text-book: and should he subject to constant revision
as fresh observations are made. The objection to system in
psychology is based on a curious misconception. Definition
and classification are no Procrustean bed ; they form rather a
scaffolding which changes constantly with the growing edifice.
Faulty definitions, inconsistent conceptions, loose enumera-
tions in place of systematic groupings, are a sheer hindrance
to progress in any science. If the introductory course is to
have a permanent value, if it is to provide a basis for further
observation and reflection, the student must clearly identify
the objects of his study, must know the precise meaning of
his terms, must apprehend the likenesses and differences of
phenomena.
The sum and substance of these suggestions issimply there-
fore: Lead your student, by seme means or other, to psy-
chologize; teach him to observe and to describe himself pri-
marily, and then other selves, in their relations, to the environ-
ment. To that end: First, teach psychology primarily as you
would if it were an end in itself. Second, eschew altogether
the method of recitation; lecture In order to sum up and to
illustrate different topics of study, but lecture sparingly; and
cultivate constructive discussion. Third, bar out the possi-
bility of memorizing text-books by requirii^ students to
precede text-book study by the experimental introspection,
and to follow text-study by the solution of concrete problems.
Finally, do not tolerate inexact thinking, but insist on clear
definition, however provisional, and on systematic grouping
of facts, however incomplete the classification.
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THE TEACHING OF ELEMENTARY PSYCHOLOGY
IN COLLEGES AND UNIVERSITIES WITH LAB-
ORATORIES.
By E. C. Sanford,
Clark UnirersUy.
To obtain data on the teaching of first year classes in psy-
chology in such institutions, the following questionary was
sent to instructors in psychology in the leading institutions
east and west with the request that they would furnish the
information desired, making replies to the questions, if so
minded, or adopting some other form of presentation, if they
should prefer.
FntsT Yeak Psychology
IHPORHATION IS DESIRED ON THX FOLLOWING POINTS
A. Purpose of the course as new given:
Is it looked upon as a means to liberal culture chiefly, as an iotroduc-
tioD to philosophical studies in general, as a subject having useful a[^-
cations, as a science to be cultivated fot itself?
If all of these ideals enter, or several of them, please indicate thar
relative importance.
B. Academic status of the course:
Is it a free elecdve, a required part of ceitain groups, a required pre-
liminary for courses other than advanced psychology, an optional course?
Does your introductory course as now given run thiough an entire
year? How many periods a week? How much bboratoty, how much
class work?
How many usually register for the course? Are they handled in one
or several sections? About what proportion go on to take further work
in psychology?
C. Content of the course:
On what is the chief emphasis laid in the course: psychological theory,
physiologica] and experimental matters, relations to daily life, pedago-
gical and other applications?
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COLLBGBS AND VNIVBKSITIES WITH LABORATORIES SS
Do you tiy to do anything with comparative psychology (animals),
child psychology, mental and nervous diseases, psychologjcal question;
of the day such as hypnotism, telepathy, mental healing, psychology
of testimony and the like?
If all or several of these topics are treated, please give the relative im-
portance attached to them.
D. Methods of instruction:
Lectures, text-book (one chiefly, or several at a time) , collateral reading,
reports by students, themes, discussions, seminary work, individual con-
ferences— which of these, or which combination of them, do you find most
satisfactory?
Do you give the students special pedagogical assistance in the way of
outlines, reviews with or without speual review questions, quizzes, oi
examinations other than those for the determination of academic stand
ing?
Do you give much oi little time to class demonstrations and experi-
ments?
Is individual laboratory work required or optional? How many hours
a week are given to it? How many laboratory hours are counted as equi-
valent to one recitation hour?
How large laboratoiy sections an handled at any one time? Do you
work alone, or do you have legular paid assistants or student assistants?
Does laboiatory work run throughout the yeai or is it begun after a
peiiod of class instruction?
Do you follow a systematic couise of experimenL"- required of all labor-
atory students — one of your own, oi a text-book?
Do you think it well for all students to work at the same time at the
same experiments or each individually (or in small groups) at a separate
problem?
Do you have the laboratory students toward the end of the year under-
take anything like minor research problems or the repetition of special
experiments from research literature?
Are you reqxinsible for classes in any other subject than psychology?
Laboratory equipment: Number of rooms, large or small.
Are you pretty well equipped or do you have to make use of a good
many makeshifts? Have you a workshop?
Have you a fairly adequate appropriation for running expenses or are
you cramped?
£. Possible improvements in the first year's work in psychology:
In what direction would you like to see the first year's work in your
own institution develop? What would you change if you had a free
hand?
What do you find the chief difficulty in giving such a course as you
would like?
On the instructional side — ^immaturity of the students, lack of pre-
liminary training on their part in phy^ology, phydcs and other sciences,
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56 S. C. SAKPOKD
lack of skiU in introspectioD, no text-book of predseiy the right scope,
insuffideot time allowed in the piogrammr of studies?
On the material side — inadequate equipment, poor quarters, insuf-
ficient help?
Do the students fail to take p^chological experiments seriously, fail
to get what the experiments mean, are shoit in manipulative skill, aie
unwtUing to give the time necessary for careful experimentation?
F. PkUanthropkal:
Have you a general list of reading in periodicals and the like, outside
the ordinaiy psychological tests, which you have found useful in the work
with first year classes and which you would be willing to contribute tc a
bibliogiaphy of recommended " outside reading," if one should be append-
ed to the report of the committee?
Have you similariy any especially good demonstrations or simfde ex-
periments, not found in such good fonn (ot not found at all) in the man-
uals, which you would be wilUng to publish in the report, or otherwise,
foi the general good?
Have you any ^>edal pie. es of demonst rational apparatus or apparatus
for student practice courses which you have found especially convenient
and which have not yet been described?
Finally, have you any suggestion.- not extorted by the above queries
as to wl^t ought to be done in a first year's course in psychology
or as to points on which this committee could obtain information that
would be helpful to you?
Most of those who replied answered the questions as
given, a few however took advantage of the latitude
offered and gave the information in other forms. In the
minds of the sub-committee such freedom of reply was more
valuable than an enforced uniformity which would have
allowed a statistical treatment of the data. In what follows,
therefore, we shall deal with rough proportions only and not
attempt tabular statements.
In presenting this report the sub-committee wishes to make
grateful acknowledgements to those in chai^ of the work in
psychology, in the thirty or more institutions responding, for
the friendly cooperation without which the undertaking would
have been quite impossible.
The following institutions responded: Brown, Bryn Mawi, Califor-
nia, Cincinnati, Chicago, Clark College, Columbia, Cornell, Harvard,
Hobart, Illinois, Iowa, Johns Hopkins, Michigan, Miimesota, Mt. Hol-
yoke, Nebraska, New York University, Ohio State University, PennsyU
vania, Princeton, Smith, Teachers College (Columbia Uiuversity), Texas,
Toronto, Vassar, Washington (St. Louis), George Washington, Welles-
ley, Wisconsin, Wyoming, Yale.
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COLLBGBS AND VKIVSKSITIBS WITH LABORATOKIES 57
The typical beginner's course in psychology is a course in
" general psychology. " Experimental psychology comes later
though in some of the larger institutions parallel courses are
offered and the student, if so inclined, may work from the
start in the laboratory. Our questions covered both kinds of
work and a certain amount of information has been collected
with reference to introductory laboratory courses. Our
report will therefore consist of two sections, the firstand longer
dealing with the introductory "general course," the second
with the first work in the laboratory.
THE GENERAL INTRODUCTORY COURSE.
The first year's course in psychology is often a popular one
in the sense that it gathers in a relatively large txxly of stu-
dents. In many institutions some course in "philosophy"
must be taken and psychology is the one selected. In about
one quarter of those reporting, it is a definitely required course
for all arts students and in nearly a third more it is required of
students in the educational department, of pre-medical stu-
dents and of those desiring certification as teachers. In more
than half, however, it competes on an equal footing as a free-
elective, and the size of the classes testifies to the popularity
of the instructor and the subject.
The immense classes of the larger institutions 200, 300 or
400, are often handled in a single body for lectures and in a
number of smaller sections for quizzes or other reinforcements
of instruction. Where the lecture method is not used the
handling of the class in sections is of course imperative, and
these immense classes would preclude laboratory work, even
if no other reasons existed for its postponement.
The proportion of students following psychology beyond
this first course varies greatly, as might be expected, but less
than 40 per cent of the students continue in four-fifths of the
institutions reporting, and but 25 per cent or less in two-
thirds of them. The fact that large classes are enrolled year
after year shows that neither the subject nor the presentation
of it is per se repellent. The small number going further
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58 S. C. SAIIPORD
shows rather that we have to do in these large classes with a
student group whose major interests are in other directions
and who make the course in psycholc^y incidental to the main
trend of their studies.
Psychology is an important branch of human knowledge,
which has interesting bearings on every day life and vital
relations to the work of certain professions, serves excellently to
bring before the student certain fundamental questions of phil-
osophy, and is for these reasons an efHcient means of culture.
All these functions are probably present in some measure in
the minds of all instructors, but the main purpose of the
course and the relative importance of its coeffects are variously
conceived. In more than a quarter of even this group of
institutions psychology is still looked upon as first of all the
gateway to philosophy. In more than half, however, the
science is presented for its own sake chiefly and the other
results of its study (except perhaps the contribution to general
culture, which is regarded as a natural consequence of a proper
mastery of the subject) are looked upon as quite secondary.
In nearly half considerable importance is attached to the
presentation of a certain useful subject matter, and concrete-
ness and applications are emphasized. In some the cultural
purpose seems more directly in view, by which is meant, we
infer, a somewhat less detailed and technical presentation than
that used when the science is taught without ulterior con-
siderations.
In about half the cases "psychological theory" (which, as
we infer, was taken by most of those who replied to mean
systematic psychology, or psychological principles presented
in a coordinated way) receives chief emphasis. In about a
third the chief emphasis is laid upon experimental and
physiological matters; while in a few cases the relations to
daily life are especially stressed. Only two correspondents
speak of emphasizing the facts of the mental life, but this
may be due to the way in which the question was phrased and
it would perhaps be fair to count all that do not specify philo-
sophical tendencies or psychological principles as tending in
this direction. The central theme is of course the mind of
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i COLLEGES AND UNIVERSITIES WITB LABORATORIBS 59
the normal human adult and in some cases there is small
departure from it. The mental life of animals and children
and mental disease are referred to in a merely incidental way
and for illustration. In a few cases, however, where the
instructor's interest and equipment are adequate, some atten-
tion is given to borderland phenomena, child psychology and
mental and nervous diseases. Topics of popular interest are
often taken up with a view to combating superstition and
popular error.
In about half the institutions reporting there is at least one
instructor devoting himself to psychology exclusively. In
the larger institutions with parallel courses, the instructor
giving the general course gives courses also in one or more of
the philosophical branches, the work in psycholt^y being his
less important function. The instructor giving the more
special (experimental) course is usually free from such
entanglements. In a few cases in the less differentiated
departments the instructor in psycholc^y takes a single class
for his overburdened philosophical colleagues, usually in logic,
ethics or esthetics; or else carries work in pedagogy.
As regards method the course is usually a mixed text book
and lecture course, though in some cases a text alone or lec-
tures alone are mentioned. Demonstrations are frequent,
especially when the central nervous system and sensation are
under consideration, and in a few cases simple experiments are
made in the class or by the students individually at home, e.g.,
such as are found in Seashore's manual. Actual laboratory
work is not usually attempted. Of the other pedagogical
devices, discussions (probably the ordinary class discussions are
meant) are most frequently mentioned ; and collateral reading,
theme wri ting, studentreportsandindividualconferencesfollow
in the order named. The quiz appears in some form in nearly
every report. Sometimes it is written, sometimes oral, some
times it occurs once or twice a semester and is an hour long,
sometimes weekly or oftener and occupies 5 or 10 minutes.
In one college all the papers turned in, in a monthly test, are
corrected and returned to the students, in another, where a
five minute written quiz is employed, the plan calls for the
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6o S. C. SANFOMD
marking of but one-quarter of the papers each time. In
about a third of the institutions reporting something in the
way of an outline or syllabus or special set of review questions
is furnished the student as an aid. A happy variant of the
review questions is that of issuing questions which cannot be
anstuered directly from the text or lectures and which require some
active response on the part of the student. In one instance this
has gone even a step further and questions are g^ven which
demand a certain amount of simple introsptection or experi-
mentation or both. In this way a real acquaintance with
mental facts is cultivated.
With so much in recall of the generally familiar situation,
let us hear the instructors on their chief hindrances and what
they would change if they had a free hand.
Inconveniently large classes or a lack of assistance is men-
tioned as a serious difficulty by about a third of those report-
ing, but this is perhaps less an evil than the dearth of students,
which is once mentioned. Lack of equipment or inconven-
ien<% in quarters is mentioned by about a third, also. More
than half find the students ill prepared for psychological work,
especially in being unable to use the knowledge of physics
and physiology which they are supposed to possess, and in
1 heir inability to introspect. Some find themselves hindered
by the mixed and uneven character of the classes in these
and other respects. One or two mention the student's unwill-
ingness to work, or his overinterest in the practical (pedagogi-
cal) aspects of the science. More, however, report no lack
of enthusiasm on the part of the students, and one or two
feel that immature students are the teacher's excuse for being,
or state as their chief difficulties their own subjective limita-
tions. The lack of a first rate text book is mentioned a number
of times and insufficient time in the program of studies per-
haps as often. Only two mention specifically the hostility of
superior officers to scientific psycholc^y.
In answer to the question as to how they would like to
alter their courses if free to do so, about one-half the instruc-
tors in question reply that they would make the work more
concrete and tangible and especially would add more demon-
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COLLBCBS AND UNIVSKSITIES WITH LABORATORIES 61
strational and experimental work; one or two would even like
to see laboratory work required o{ every student as in chemis-
try and physics. Nearly a third would be glad of more assis-
tants in order that the classes might be handled in smaller
sections and the students receive more individual attention.
Some of these difficulties and desires are by no means pecul-
liar to psychology, and could be matched from almost any
department in any growing institution. Too lai^ classes,
too few assistants and unsatisfactory quarters are the common
lot of nearly all instructors in nearly all sciences. The same
is true in a measure of the immaturity and imperfect training
of the students. The suggestion, however, that their defi-
ciency in these particulars is only a sign that they need a
teacher meets the matter in part only: there seems to be a
real difficulty here and one resting with especial w«ght on
psychology. Inability to introspect means inability to get
at the subject matter of psychological science and points to
an unusual danger of substituting a knowledge of words and
descriptions of psychical phenomena for knowledge of the
things themselves. This in the committee's opinion is a.
matter of first class importance and needs the attention of
every teacher of beginners in psychology.
The frequent desire for more demonstrations and more
expjeriments in the beginner's course may possibly mean a
wish for a more striking lecture material only, but it ought
to mean a desire for a closer envisagement of the psychic
facts by the pupil.
The fact that many students whose main interest lies else-
where are now drawn into the first year's classes in psycholf^y
and that introspection is a hard matter at the best would
seem to make the opening of their inner eyes to the mental
world one of the first and most imperative duties of the course.
Practical bars of the most insuperable sort hinder the accom-
plishment of this by regular work in the laboratory. The
classes are almost everywhere too large and the amount of
time which the students can give to psychology too small.
What is wanted is clearly some other method of bringing the
student into contact with the psychical facts. Something is
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69 e. C. SA.VfORD
already being done, and often a good deal, in the way of
demonstrations and class experiments and this is in every
way admirable when the instructor makes use of the intro-
spective possibilities which they offer and drives home the
psychological meaning of what is presented. But the b^n-
nings which have been made in the issuing of questions requir-
ing simple introspections and experiments, and in the prepara-
tion of simple experimental courses which can be followed by
the student at home as a part of the regular preparation for
the lecture or recitation hour, are undoubtedly still more
important steps in the right direction and worthy of all
encouragemen ts.
The most interesting and valuable of the information
brought out by our questions was that which a number of
our colleagues were kind enough to give in reply to a portion
of our last question which read as follows:
" Finally, have you any suggestions not extorted by the above queries
as to what ought to be done in a first year's course io psychology?"
Several of these paragraphs of suggestion we desiie to give In extettso.
SUGGESTIONS FOR THE IHFBOVEHENT 0? THE GENERAL COOKSE.
I. "But seveial things are needed for the improvement of courses
like A (a "geneial course"). ... I might mention:
" (i) A good reliable list (a) of inexpensive demonstrational apparatus
and (b) of useful demonstrational experiments, whose use with the class
would occupy a veiy small proportion of its time, but would serve not
merely for its entertainment but as a real help in comprehending the facts
and prindples discussed. I am not fully satisfied yet with existing lists.
" (a) A good crilicai bibliography on «ch phase of the subject.
"(3) A standard set of lantern slides.
" (4) A larger agreement among the leading psychologists as to what
are the fixed and permanent underlying prindples of the sdence.
"(5) An adequate text book that will emphasize these fundamental
prindples first of all, aiming to present them soundly and (x>nvindngly
with only enough of detailed fact to make these essential prindples dear;
leaving to lectures and collateral reading the acquisition of further de-
tails and the application of the fundamental principles to them. At
present to reach this ideal, I suppose each of tis must write his own text
book; for I haven't found one yet that satisfies me."
U. "I am of the opinion that a General Introductory Course that u
required should not be a laboratory course. Too little can be covered in
such a course and to my mind the advantage of the laboratory method
should, under the circumstances, be sacrificed for the sake of the greater
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COLLBGBS AND VNIVBKSITIRS WITB LABORATORIES 63
advajitages of & course of wider scope, and such as can be given in the same
time in lectures supplemented by copious demonstrations.
"If the course is not required and if most of the students take further
work, in Psychology the force of the above objection is gieatly reduced.
Nevertheless, even in this case, a general lecture course with demon-
strations and class experiments is to be preferred by way of introduction
to a strict laboratory one.
" I insist in my general required course upon the structure, the organ-
ization and the function of the nervous system. This seems to me re-
quisite not only for a proper understanding of psychology as a science,
but also for a modem understandii^ of man and his activities. This
general culture value of a clear and not too scrappy understanding of the
organization and of the function of the nervous system is, to my mind,
of the first importance in a required course."
III. " I. Business-like administration is desirable in the interest of
the student, who is likely to get into slovenly habits. Tc this end W — has
found nothing bettei up to date, than dividing each half yeai's work
into 5 parts, each part being a subject, such as space perception, associa-
tion, memory, reaction time; the work on each part is to be completed
at a previously set date, the laboratory notes to be handed in, and an
examination on that part taken.
"3. Instead of asdgned cultural readings W — piefeir, usually, prob-
lems to be worked out by the student; as for example (a)illu£trationsof
Weber's law from common life (usually not very successful); (b) records
of trains of assodaUoQ; (c) exercises in finding aveiage, constant and
variable errors, etc."
IV. "Standardize by getting (and recommending) good sense organ
and central nervous system slides and models. By suggesting certain
sets of demonstrations. . . . (but) leavmg time for instnictorial
bent.
"Arrange some exchanges of first year examination papers between
different univeisities."
V. "I would suggest that the committee prepare or further the prepa-
ration of leaflets or pamphlets containing directions for ^ngle experi-
ments or groups of experiments in order that instructors may make any
combination suited to their needs. Even the smaller manuals contain
much not suited to some classes."
VI. "I would suggest that a loosf leaf laboratory book be prepared,
corresponding to books now used in physics, chemistiy, etc., describing
a series of simple experiments and containing all the material necessary
for perfomu'ng the experiments. If the experiments were performed
undei constant conditions, and the records sent to some central body, we
should be in possession of some psychologic norms with which we could
compare the results given by our own students. I have a lot (A this
stuff worked out now and should be glad to cooperate."
VII. "The thing that more than any other keeps us to the old lines is
the belief that the beginning student should get a firm grip on the vocab-
ulary of psychology, even if that vocabulary is somewhat archaic, and
that a study at first limited to the normal, human, adult mind, is best
for that purpose."
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64 B. C. SANPORD
Vni. "If my observations are correct Experimental Psychology is
Qow taken (elected) by only a few students. The way to save this work
for education is to combine its essentials with the introductory course,
I sincerely believe. Experimental psychology has an 'educative' value
in various ways but now this is almost entirely lost. Combining the
essentials with the introductory course would also assist in giving the
essentials of the text book. I used Seashore's Elementary Experiments in
my begiiming classs this year and found it deddedly helpful."
IX. "With respect to ordinary college first year psychology my main
divergences from customary opinion are:
" (i) That this course in psychology is not to make philosophers.
"(a) That this course in psychology is not to make psychologists.
" (3) That this course in psychology is to make men and women better
fitted to understand all the sciences and arts dealing with human natuie.
" (4) That psychology is not best taught to beginners as the study of
human consciousness but as the study of human nature and behavior.
" (s) That expeiiment dealing with realities and exercises testing knowl-
edge and power by demanding their application to new problems are a
sine qua non of success in teaching psychology (01 anything else).
" (6) That the function of the teacher is not primarily to get a great
amount of work done by the students but to get the greatest amount of
knowledge, skill, etc., fiom a given amount of work b> them.
" {7) That the actual content of the course is more important than most
teachers of psychology think and the form 01 disdpUne or foint of view,
etc., less impoitaot."
X. "If conditions permitted it, I should be in favor of giving a whole
year to the required course, in which the only labotatory work would
be of a practice character. In such a care I would like to see the dynamic,
rather than the static, aspects of mind emphasized. I would begin the
course, not with a detailed analysis of sensation but with a consideration
of the biological functions and place of the human mind. Then I would
proceed to more careful analysis with experimental illustration. I would
spend a good deal of time on the psychology of conduct, thinking, feeling,
bringing out the connection between ethics, logic, esthetics, etc., and
psydiological analysis. I would give some attention to abnormalities
of consciousness and action and point out the practical, social, moral and
educational bearing of psychology.
"Whatever may be said in favor of a structure psychology that is
rigorously atomistic, as a legitimate scientific proceeding. . . . my
experience as a teacher leads me to say that emphasis on the stiuctural,
static, and atomistic points of view is not desirable in a first year course.
" Whatever the value or interest of these very vague remarks, they are
to be taken as the expression of a teachei who, while lecognizing the inde-
pendent rights of psychology, does not deem it wise, from the standpoint
of undergraduate instruction and of philosophical culture, to divorce
if from philosophy. In fact, as one whose interests are predominently
epistemological, ethical and metaphysical, I am not at present able to
draw any ^larp dividing Une between functional psychology and philos-
ophy."
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COLLSCBS AND VNIVEgSlTlES WITB LABOKATORIBS 6$
XI. " A satisfactory consensus of opinion, today, I think is impossible
to obtain; and such as you will get I consider more likely to do haim than
good, except possibly in the smaller colleges. ... I consider the
attempt to standardize courses premature; let the men in the field expeii-
meat with couises, the best will survive; but your made to ordei course
or your average cou.s.e will never be as good as tbe best ."
XII. "I do not think that it is possible to teach a science in any other
way than as a "science to be cultivated for itself." That is to say, I
should give precisely the same introductory course, whatever the aims
and needs of the students who took it. I doubt whether it is advisable
to cut a science to suit the requirements even of a distinct professional
course; I doubt, that is, if it is advisable to teach English Literature for
Engineers or Physiology for Medical Students; I believe that the best
results are gained, in such cases, by teaching English literature and phyd-
ology. But 'general culture' or 'hberal education' — the supposed main
object of college courses in arts and sciences — is not a profession, is not
at all strictly definable; and I do not see bow it is possible, not to say
desirable, to cut psychology to fit that requirement.
"I teach psychology, at the beginning, in an elementary maimer. I
make things as simple as possible; I omit phases of problems, even whole
problems, where simplification to the necessary degree is impossible; I
am dogmatic on points where dogmatism is strictly out of place, although
the dogmatic statements are always qualified for those who have ears to
hear. But I am all the while teacliing psychology, as best I can, without
ulterior motive or ideal. I get a good many men from engineering,
medicine and law; the number of these outside students is steadily in-
creasing; but I make no conces^ons to them.
" If any other ideal is followed, it seems to me that one of two things
must happen. Either the teacher lapses into dilettantism; and for this
there is no defence. Or the teacher substitutes his personal and private
judgment for the objective judgment embodied in the actual course and
growth of the sdence; he forces on the students his own notion of cul-
tural or philosophical or practical application, instead of showing what
has been accomplished and allowing that accomplishment to sp^k for
itself. In general, this alternative must lead to bad results.
" I graat, of course, that a teacher, a man who is in love with his sub-
ject, mil do well with students whatever method he follows and whatever
choice he make. That is axiomatic. But I suppose that the aim oi
this questionary is to help the weaker brethren, and not to legislate for
those who already know. And I should accordingly counsel the weaker
brother, if he is a professor of psychology, to teach psychology. If he
does this, up to his honest limit of achievement, he will find that psych<d-
ogy will show its own bearing upon culture, its own philosophical rele-
vance, its own applicability. These references may then be followed up,
as needs arise and as the size of the staff allows, by later couises, given
either by the department of psychology or by those of philosophy and edu-
cation, etc. To interject them at the b^mning is to warp the mind of
tbe student. . . .
" My ideal is the local separation of the college from the university.
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66 B. C. SAirPORD
With this ideal realized, I sliould offer (i) an introductoiy course, mudi
as I do DOW, for graduates in other departments, and (a) research and
training courses in the laboratory. I should not, by dioice, be a 'college'
professor. Being this, however, I have rigorously pushed my univeruty
ideals into the college work. The success is patent; my 370 elective
students — if thdr number is compared with the number of the sophomore
students in the collie — are sufficient witness. To say that hard wotIi
cannot be got out of the students, or to say that scientific psychology
is uninteresting, is simply to covei up one's own laziness or incompe-
tence.
"I must here interject my ideas on the lecture system. The lecture
has a twofold advantage over the recitation. (1) It is economical, ^ce
one man handles a large number of students; the method of recitation
is extravagant. This fact alone will mean the retention of the lecture
system, wherever it can posfibly be employed with success. (2) It is
educationally the better method, for the average student and the aver-
age teacher. For the reconstruction of a lectme from notes means an
essay in original work, in original thinking; while the redtation lapses
all too readily into text-book rote and verbal repetition.
"It is, nevertheless, true that sophomore students are on the whtde
inadequate to a lecture course. They cannot take notm; they cannot
tear the heait out of a lecture. (They are also, I may add, inadequate
to the reading of textbooks or general liteiature, in much the same way.)
Hence one has to supplement the lecture by syllabi, by lists of questions
(indexes, so to speak, to the lectures), and by personal interviews. I
spend, on the aveiage, 8 hours of time on every one of my sophomore
lectures; I give 34 hours a week to a 3 houis' course. But, doing this, I
secure a fail-percentage of 2 or under.
" Evidently, this method is wasteful of good mateiial. While it costs
less than it would cost to add half a dozen assistants for recitations; and
while it is also, educationally, a better method than that, it still wastes
good professoiial time. The remedy, is, to accustom students to note-
taking in the high school. In the Engl^ public schools, a part of the
work in the upper forms is lecture-work, for which the boys are hdd
responsible; they therefore go to the um'veisity in some measuie prepared
for the lecture courses. Now lectures are frequently given, by outsiders,
to the students in American high schools; but they are looked upon as a
recreation or a bore. I suggest that these iectuies, given once or twice
a term through the four years, might be utilized for teaching the students
to take notes. The students might, in a minor way, be held responsible
for the reproduction of their contents. Then, in the fieshman year, the
student might take, say a single lecture course of 3 hours a week; so that,
in the sophomore yeai , he would come to the psychologist with some train-
ing.
"I speak of averages all the way through. A man may be a bora lec^
turer, or a bom usei of the Socratic method; he will succeed anywhere.
But we do not get congenital ability i^hroughout our faculties. I betiere
in the lecture system, for the average student and the average instructor
of our subject, but I suggest that the present state of affairs might be im-
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COLLBGBS AND VNIVBXSITIBS WITB LABORATORIES 67
proved, on the side of the student, by better high school pteporation. As
for the instructor, he must be taught, as sharply as necessary, that a lec-
ture is a work of art, and not a perfunctory delivery of information.
Murh of the failure to interest, in psycholr^, is due to the instructor's
lack of educati<Hi in hi; art: he cannot manage his voice, he has nol learned
what he wants to say, he does not propeily enunciate, he cannot vary
from narrative to exposition, to argument; bis anecdotes are purfde
patches and not relevant lightenings of the material Time and again
Ihave listened to'lectures in psychology' that made me wish I had the
lecturer alone, with nothing but the moral law in my heart and the uni-
verse of stars above me. . . .
" So — to return — my chief difficulty is immaturity of training (not of
mind) on the part of the students. Physiology and physics they have
tasted, or can get concomitantly; introspection it is my business to teach
them; text-books I can write myself; and I have my share of theii time.
I want tbem only to know how to deal with spoken oi printed material.
" Our equipment I have already described. Students who lack serious-
ness, or understanding, or manipulative skill, or time to devote to the
subject, are bowed out of the laboratory in the course of the first fort-
night. Why shoidd we bother with themP They are not obliged to
come in, and we are assuredly not obliged to hold them if they do come
io. We take all imaginable pains with the real student, whatever he may
at first be lacking in; but the unfit are eliminated. And if one has had
rxperience, the spotting of the unfit is not a very difficult thing.
" I should deprecate the publication of any list of first yeai 's collateral
reading. The science is growing by leaps and bounds, and the collateral
reading shifts and changes from year to yeai. To publish a list would
be to relieve the instructor, for some years to come, of what should be
an integral and an interesting part of his own work and growth. The list
would remain, fossilized, and students would suffer. No conixssions
should be made, I think, to the weakness of the instructor; every allow-
anoe should be made for the poor training of the student. . . .
"The sum and substance ot my lecommendations is that you provide
a competently trained instructor, and let him teach psychology as he best
can. What the student needs is the effect of an imUviduality, a person-
ality; and the lecture system provides admirably for such eSect. I
shoiUd strcHigly deprecate the issuance of any general plan of organiza-
tion, or the authoritative lecommendation of any special t(^ics or pro-
cedure, which should tend to mechanise instruction in the colleges. We
are overorganized, ovet-businesslike already. I venture to suggest that
a great dangei in the Report of the Committee lies ptedsdy in this point.
If its recommendations are over-stringent, if the fieest play is not allowed
to the instructor's personal tiainii^ and individual capacity, we shall be
out of the frying pan into the fiie.'"
> Seven! comspoadaxts would like to have iufomutiQn u to particuUr questions
with reference to the &rat year's course — as, for example, the prefeired order of presen-
atioB of the vaiious topici in the conne, whether mtioducbHy ezperimental woik
bouM b^in with bore sense-ezperiments, how fu psychologists fed an unaaUsfactoir
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68 E. C. SANFOltD
RecommendtUions. . The Committee has no such idea of its
function as that implied in the warning of our colleagues who
penned extracts XI and XII above. It does not desire to be
responsible for an average course or to standardize the courses
now given. It agrees unreservedly with the writer of extract
XII that the best way in which to secure good courses in psy-
chology is to select well trained men and give them a free
hand. Good teaching is an art and the teacher must be
assured the artist's freedom. The Committee's function, as
we conceive it, is not to establish norms of any sort, but to
formulate more clearly certain ideals on which many or all of
those teaching psychology are already agreed, to point out
means by which these can in some measure be realized, and
finally to recommend to the Association such action as will
assist those who care to work in the direction suggested.
The ideal which the Committee desires to formulate and
for which it hopes the endorsement of the Association is that
of the fullest possible acquaintance on the part of the student
with the concrete facts of consciousness as the rational basis
for a knowledge of psychology — an ideal which has been
frequently mentioned by our correspondents and which is
shared we believe by all or almost all of our colleagues. As
means to this end the Committee urges, as indicated above,
the fullest use of demonstrations and class experiments, given
always in such a way that the student shall not fail to grasp
their psychological meaning, and the development of the
scheme of simple home experiments and introspections already
in tentative use by at least two of our colleagues.
In furtherance of these ends it recommends to the Associa-
tion the formation of two permanent committees, one on
Demonstrations and Class Experiments and another on Psy-
chological Experiments Outside the Laboratory. The func-
tions of the first should be to publish from time to time in
some one of the psychological journals, first a classified bibli-
ography of such good demonstrations and class experiments
tendency toward practicality in the students which come to them from pedagogy, and
how far they still suffer from a tendency of philosophers to dominate the departmoiti
to which the psychological courses belong.
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COLLEGES AND UHIVERSITIES WITB LABORATORIES 69
as already exist in readily accessible literature, second to
collect and publish in full in the same way directions for mak-
ing such demonstrations and class experiments as are found
only in relatively inaccessible literature, and third to collect
and publish in the same way similar demonstrations, experi-
ments and descriptions of demonstrational apparatus as
are now in use in American laboratories and as yet unpub-
lished. (Several of our correspondents have already signified
their willingness to contribute to such a collection.') The
Committee on Experiments Outside the Laboratory should
undertake the same functions with reference to their particular
topic. Our purpose in suggesting that these committees be
made permanent is that they may be given time to work
slowly at the material to be gathered and publish from time
to time as it is collected without producing at once, or waiting
for, anything approaching a complete exploitation of the
field; and that the experiments and demonstrations which
they publish may be kept up to date.
THE FIRST YEAR IN THE LABORATORY.
In the half dozen or more institutions tn which parallel
introductory courses are offered, it is possible for the student
to begin the subject of psychology with its exfierimental
aspect. But even in these cases it is exceptional that a student
enters the laboratory before he has taken the general intro-
ductory course, though the two courses are sometimes carried
at the same time. In all other institutions where laboratory
work is given at all, it follows an introductory course. The
first laboratory course usually runs through a full year though
in some instances it is given in a single semester.
The preferred size of laboratory sections is ten or under,
though in some institutions, where the work has been thor-
oughly systematized larger sections (up to 30) are handled
by the instructor with one or more assistants. Practical
' We would suggest for membenhip on this latter committee our colleagues Pfofetsor
J. E. Lough of New Voric University uid Professor Margaret Floy Washburn of Vasau
Colhc* who have already used with success the methods in questioo.
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TO E. C. SAHFOJtD
reasons, especially the cost of much duplicating of apparatus,
make it necessary in most cases where the laboratory sections
are at all numerous, for different groups to work at different
problems, but some instructors in beginning the laboratory
course have all the students work at the same problem at the
same time until several problems have been covered; and in
exceptional circumstances it has been found best to carry this
method through the major part or even the whole of the
beginner's course.
After a year or so of laboratory practice several teachers
set students at repeating experiments from research literature
or assign them minor research problems under supervision.
It is rare, however, that this can be done within the first year.
In the institutions in question the number of rooms used
for laboratory purposes ranges from i to 32, but in the latter
case of course many rooms are included which arenot used for
the first year's laboratory courses. The most frequent num-
ber mentioned is 5, and half of all reporting give numbers
from 2 to 7. In two institutions the laboratory consists of
one room only though in one of these cases other rooms may
be used in time of need.
In equipment most of the laboratories supplying informa-
tion (about two dozen) are at least fairly equipped for the
sort of work required. Only three speak of their equipment
as inadequate, and one of liiese is just starting.
Appropriations are felt to be inadequate and cramping in
but four of twenty eight; and some small laboratories are
able, by economy and by concentrating research upon a
single topic at a time, to do work of excellent quality, both
practice work and research, with the expenditure of rela-
tively small sums.
With reference to the constitution of the first year's labora-
tory course there is a wide spread diversity. Eclectic courses
are common and it is once or twice remarked that the course
is varied from year to year or should be adaptable to the needs
of the students taking it. It must often be limited also by
the equipment, or even the physical situation, of the labora-
tory.
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COLLEGES AND aiflVEXSITIES WITH LABOKATORIBS JI
The data collected with reference to the first year's work
in the laboratory, while it shows that most of the laboratories
reporting are in a fairly prosperous condition is sufficient to
to justify the Committee in but a single recommendation.
Recommendation. In view of the diversity of interest,
requirement and possibility the Committee looks with favor
upon the suggestion of one of its correspondents that a labora-
tory course should be prepared on the principle of the " loose
leaf" courses now used for elementary laboratory work in
other sciences, by means of which an instructor can vary his
course with ease and within wide limits. The preparation of
such a course is not the work of the Association nor of a com-
mittee working under its authority, but we suggest that, if
so moved, the Association might further such an undertaking
by expressing its official approval of the plan.
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LABORATORY COURSES AND EQUIPMENT IN PSY-
CHOLOGY FOR COLLEGES AND UNIVERSITIES.
By Jaues R. Angell.
University of Chicago.
The two points in our educational system at which advice
is most often sought concerning the equipment of a labora-
tory for psychology are the normal school and the small
college each with a modest appropriation at disposal for the
purchase of apparatus. The normal schools are treated in
another part of this general report. The comments which
follow are directed to the consideration of collegiate institu-
tions which pwssess no equipment in psychology or to those
whose equipment is small and who may contemplate either
systematic or occasional enlai^ment. What is said of
research pertains primarily to the larger universities, but it
is included with brevity for completeness sake. Such insti-
tutions ordinarily require little advice and would be slow to
accept it, even if it were needed.
MEANS AND ENDS OF LABORATORY WORK.
Laboratory work in psychology may be designed to meet
any one of several distinct aims of which three may be men-
tioned, (i) It may be desired to offer students laboratory
methods primarily as a means of aiding them to attain direct,
personal contact with psychological materials, to assist them
in introspective observation and in general to supply them
with a technique for discovering facts about mental processes
and for arranging and presenting these facts when obtained.
(2) Another proper aim of laboratory work, which includes
but goes beyond the one first described, is that of furnishing
students immediate acquaintance with the apparatus and
methods by which important facts have been determined and
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LABORATORIBS AND BQUIPUBNT 73
significant principles established. When the opportunities
of a well-equipped laboratory are improved to the utmost
in this direction, students not only secure an excellent drill
in general scientific method, but they also gain the ability
to estimate with confidence and independence the relative
reliability and certainty of specific types of procedure. In
other words they begin to achieve scientific judgment. (3)
A third aim is that of research, together with the giving of a
thorough training in experimental technique as a preliminary
for it. Many other purposes may be involved from time to
time, but these three alone afford grounds for very consider-
able diversity in the equipment required for their realization
the first differing much more from the latter two than they
differ from one another.
The first aim demands much the least pretentious outfit of
materials and may be attained with large success on the basis
of a very slender equipment, such as can be secured at trivia!
expense. The exercises in introspection which certain of
our texts now contain and the ground covered in one or two
manuals at present on the market well supply the need for
work of this kind. To be sure many of these exercises could
not be called strictly experimental in character inasmuch as
they simply invite attention to certain facts open to casual
observation. But they shade over into a more genuinely
experimental procedure by indiscernible gradations and for
our present purposes they may well be ranked as experi-
mental.
So far as our reports enable us to judge, the results gained
by this type of work have been most salutary both in convey-
ing a just impression of experimental method and in stimulat-
ing appreciation for direct psychological information. Teach-
ing institutions of all kinds in which psychology is repre-
sented may well be ui^ed to make use of the possibilities of
work of this sort. It must not be ex^^erated in importance
as in any way taking the place of the varieties of work still
to be described. It is in no sense justly to be considered as in
competition with them. It supplies a different need for a
different constituency. But it can hardly be neglected by
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74 JAUBS R. ANGSLL
any instructor who desires his students to secure vital ideas
of the character of psychological facts. Every good teacher
has used it more or less since the beginning of the experi-
mental movement. It deserves, however, to be employed in
the most effective manner possible and for this result much
intelligent planning is necessary. Formal apparatus although
distinctly useful is altogether secondary. In any case, whether
with or without apparatus, the procedure is designed to bring
out the rudimentary mental phenomena, such as those of the
various sense experiences, attention, memory, imagery, feeling
and the like.
In this connection should be mentioned also the class experi-
ment which shares with this form of procedure just mentioned
the essential aims designated but attempts to reach its ends
by methods that permit the class to work as a group, thus
economizing the time of the instructor and the expense of pro-
viding assistants such as are usually required for the super-
vision of laboratory exercises. This is not the place to discuss
the merits and defects of this method. Suffice it to say that
experience has shown conclusively that much can be done in
this way to give accurate impressions of experimental method
and not a little can be accomplished in the actual disclosure
of unfamiliar psychological fact. The manipulation of psy-
chological data can also be effectively taught or at least illus-
trated in this way.
The use of demonstrational materials of all sorts may well
be mentioned here. Of the value of such devices when
properly employed there can be no question whatever. The
verdict of experience is unequivocal on the matter. They
add to the interest of the class, increase the breadth of out-
look and linger firmly in the memory by virtue of the vivid-
ness of the experience which generally attends their use.
They suffer from the danger of incompetent use as do other
meritorious means of instruction. If they are not used so
as definitely to assist the mastery of the matters immediately
in hand, if they are introduced so as to constitute a diversion,
if they are used with so much frequency that the main impres-
sion conveyed by the course is one of a vaudeville character.
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LABORATORIES AND EQUIPMEST 75
they are not likely to prove anything but disintegrating to
the final result.
The second main aim above mentioned, «.«., systematic
training with classical forms of apparatus, requires for its
complete realization a lai^e and relatively expensive equip-
ment of apparatus. Such a collection must keep abreast of
the time and must be well supplied with the classical pieces
of apparatus many of which are inevitably costly. But the
expense brings a fine return to the student fortunate enough
to be trained in such a laboratory by a man conversant with
his field and enthusiastic in its cultivation. No other means
can afford so firm a grip upon psycholt^cal science. For a
laboratory established with this second aim in view a realty
good shop is of the very highest value and some sort of place
for minor tinkering is absolutely indispensable.
The most perplexing problem which institutions have to
face in the matter of equipping for work in psychology is
found in cases, which come fairly under the second main
heading, where funds enough are available to permit some
measure of freedom in purchasing apparatus, but where not
enough is at hand to allow any completeness in outfitting.
The question at once arises what to secure. It may be a part
of the later work of this committee or its successor to make
explicit suggestions toward combinations of apparatus where
such conditions prevail. If so, no doubt such suggestion
will be forthcoming. At present only a few comments on
alternative courses will be offered.
One possible line of action involves a selection from among
the various pieces of apparatus of such as may be thought best
fitted to convey a generally accurate impression of the scope
and character of experimental work. In this case personal
preference as to lines of work to be emphasized will naturally
differ. The private interests of the instructor will inevitably,
and perhaps properly, dominate the choices. Such a collec*
tion will be frankly imperfect, but it will not be wholly one-
sided.
Anoth^ line of procedure contemplates the selection of one
special field of work, such for instance as that of vision, and
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76 JAMES R. ASGELL
the making of the most perfect possible collection of appara-
tus designed to permit thorough exploration and demonstra-
tion of all the features of that field. This course will inevit-
ably leave one with a collection quite unrepresentative of the
general experimental situation, but it will enable the giving
of thorough training in some one direction, it will ordinarily
permit the undertaking of stimulating research and, inasmuch
as the technique of scientific method is highly similar in many
fields of endeavor, it will render possible a very satisfactory
training in experimentation. Certainly the advant^es of
this choice for the expenditure of funds in cases where the
amount at disposal is quite limited, deserve much more atten-
tion than has commonly been given them. In combination
with the possibilities of the firat general type of procedure
described above where Httle or no apparatus is required, it
offers opportunity for most striking results.
When we come to speak of our third aim, ».e., research we,
find ourselves confronted by divergencies similar to those
which we have just discussed. It may be laid down as a
general axiom that an ideal research laboratory should be
equipped to afford the best and most symmetrical training
of a disciplinary kind such as has been considered under the
immediately preceding heading. In point of fact, however,
much good work has come from laboratories where very
different conditions prevail. Successful investigation is of
course partly a matter of resources, but it is much more
lai^ely a matter of the man conducting it: it has at its best
the spark of genius in it and all attempts to reduce it to rules
or restrictions are futile and fatuous. Nevertheless, we may
certainly recognize those conditions under which it is most
likely to flourish and attempt to secure them where possible.
In America the general tendency has been to precede research
work by a course affording not only a general survey of the
field of experimentation, but also actual drill in the execution
of experiments in the several principal fields of scientific
interest and accomplishment. Elsewhere a different pro-
cedure has often been followed. Research has been attempted
on the basis of a very narrow acquaintance at first hand with
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LABORATORIES AND EQUIPUEHT ^^
the general experimental field. A period of service as reagent
for some other student's research, tc^ether with a preliminary
training of a theoretical kind in lecture or recitation room,
has been the only introduction required for the beginning of
original investigation. It must be admitted tiiat not a little
excellent work has been achieved on this latter basis, but it is
certainly safe to say that the first method is the only one to
be encour^ed where means are at hand to permit its estab-
lishment.
The laboratory adequate both for general training and for
original investigation is extremely expensive and is not to be
thought of save by a few of the stronger and wealthier insti-
tutions. When its advant^es are,well used it represents the
most effective organization for our work. But every one who
has lived in one of these large laboratories knows full well
the dangers which always lurk to ensnare the unwary. The
very riches of the place may contribute to lassitude and to a
dangerous sense of competency which is justified by no real
attainments. The equipment too is likely to suffer from
failure to clean it out often enough. A good bonfire should
be an attachment of every lai^ laboratory and on it should
be offered up each year the rubbish which gradually accumu-
lates, which has no historic value and which often misleads
the tyro into cherishing respect for that which should only be
forgotten. Fortunate the laboratory where only those things
are cherished which are really used and which really deserve
preservation.
In connection with a research laboratory a good shop with a
comp>etent mechanic in charge is one of the most important
assets. The efficiency of such an establishment is increased
many fold by this feature. Some of our laboratory directors
have appreciated this fact and invested what might seem to
the uninitiated a disproportionate part of their funds in this
direction. But while it is no doubt possible to equip a shop
too luxuriously, the lack of an effective shop is one of the
most serious handicapts which a laboratory for research can
labor under.
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78 JAMBS K. AirCBLL
PLACE OF EXPERIMENTAL COURSES IN THE CURRICULUU.
Experimental training under our first heading evidently
finds its place in connection with the beginner's course and
the location of this in the college work is discussed elsewhere
in this report. The case of experimental courses differen-
tiated from theelementary workoffersamoredifficultproblem.
It is the almost universal practice, where such courses are
given, to insist upon the taking of the elementary course in
general psycholc^y before entering on this work. If this
prerequisite is enforced, the place of the experimental courses
is forthwith settled. In most institutions this would in effect
limit the patron^e of the experimental work to the junior
and senior years. Experience su^ests one conclusion about
the matter which seems worthy of formulation. If the patron-
age is open to very young students, it is difficult for alabora-
tory course in psychol<^y to compete with other college
courses of an attractive kind without lowering the scientific
severity and rigor of the work to a point where its solidity
and worth must suffer in the eyes of the better students.
Many instructors prefer the most mature students possible
in order to avoid the necessity of thus cheapening the work
to carry the full interest of the class. Whether this situation
arises from incompetent teaching, from failure as yet to
develop satisfactory methods of presenting the subject matter,
or from the intrinsic character of the material, whose appre-
ciation requires a certain sobriety of interest and a certain
maturity of intelligence, in any case the conclusion just indi-
cated is an expression of the experience of many instructors.
A course can be given which shall be entertaining and moder-
ately informing without str^ning the student's tenacity
unduly. But if the work is made to contribute in a sub-
stantial way to the mastery of adequate technique and to
the achievement of accuracy and thoroughness, the tax on
student patience is greater than most young undei^aduates
will endure. In general it may be said, then, that experi-
mental courses beyond the elementary course which may well
contain some experimental material, should come late in the
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LABORATOfUBS AND EQUIPMENT 79
college curriculum. For students who plan to go at once into
graduate work of a psychological kind, this arrangement is
apparently a disadvantage. But for the rank and file this
disposition of the case is undoubtedly best and, even in the
case of the would-be specialist, it may well be urged that his
time as an undergraduate can be better employed in lines
contributory to his general training than in a too early and
narrow specializing.
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GENERAL REPORT ON THE TEACHING OF THE
ELEMENTARY COURSE IN PSYCHOLOGY:
RECOMMENDATIONS.
By C. E. Seashore.
Vnitersily of Iowa.
Be it said once for all that this committee regards it neither
feasible nor desirable to recommend any one system ofpsy-
chology, any fixed mode of treatment, or any exclusive set
of aids to instruction. The content, the method, and the
means of instruction must vary with the preparation of the
teacher, the type of student, the place of the course in the
curriculum, etc.; and the growth of science, the invention of
methods and instruments, the appearance of new text books,
etc., make it necessary to change the course from year to
year.
Nor does it seem desirable to make this general report a
summary of the subcommittee reports. The reports of the
subcommittees have been worked out independently and no
effort has been made to harmonize them. We propose that
all the reports shall stand together and each supplement the
other. Although this one is the general report, it does not
represent the unanimous opinion of themembers of the com-
mittee in all respects. It was drawn by the chairman as an
expression of his personal views after careful study of the sub-
committee reports; it was then submitted to each member of
the committee for criticism and thereupon revised by the
writer so as to represent the conviction of a majority of the
committee on each point. The committee has thus made no
effort to si>eak with authority for itself or for the Associa-
tion. Although based upon the data collected, the four
reports are largely personal.
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GEITBKAL RSPORT 8l
Yet psychology has now found itself in American institu-
tions sufKciently for us to take a provisional inventory. These
reports are an attempt at such an inventory of aims, inter-
relations, conditions, methods, equipment, etc. The com-
mittee hopes that they may stimulate interchange of ideas
on the subject and prove a starting point for further coopera-
tion toward the development of the teaching of that subject
which is the foundation for all the science and art of teaching.
A word of apology must be made for the terse, brusk, and
hortatory style. It has been followed in the interest of
brevity and clearness, and for the purpose of stimulating dis-
cussion. There is hardly a statement that should not be
qualified to meet special circumstances, and much is contro-
versial; but an explanation of this at every point would leave
the report unnecessarily cumbersome. The generalscope and
form of this report was determined by the purpose of setting
forth a series of propostions, or tenets, for discussion In the
Association. The aim has been to set out a few fundamental
principles in systematic relief.
{A) Teach Psychology.
Strange to say, this is the one exhortation most needed today. While
only a few schools lag in the old rut and teach antiquated systems of
philosophy in the name of psychology, the conunoD error today is to
ramble from the study of mental processes as such into sense physiology,
moralizing, loose pedagogy, or logical quibble.
The first course in psychology should be essentially the same
in content and method whether it is taken merely for general
culture, as a foundation for philosophical studies, or in prep-
aration for specific vocations; such as, education, theology,
art, law, or medicine.
I. Teaching psychology strictiy as a science in itself lays
the best foundation for the final mastery of the relationships
and applications of psychology.
The laying of such a broad foundation for philosophy and the numerous
applications of psychology frees the teachers of ak those subjects from
the wasteful drudgery of having to improvise psychological foundations
at each step as needed.
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83 C. E. SEASBOKS
Nothing has been more potent for the improvement of the teaching of
philosophy and psychology than the recognition of this separation for
teaching purposes. The same will be seen in medicine when normal
psychology is required as a preparation for the study of psychiatty, and
ha!s been clearly demonstrated in the recent development in the t^arhing
of educational psychology.
Supplementary instruction on the relation of physiology, logic, ethics,
philosophy, etc., to psychology may, and usually should, be put into the
course, but only when it is made clear Uiat it is not psychology.
2. In the first course the applications should be incidental
and should be distributed among different aspects of daily
life with a view to the broadening of the mental perspective
of the student; as, in education, medicine, science, art, law,
literature, philosophy, religion, business, play, labor, etc.
In a sustained iUustration of the formation of associations in Q'pe-
writing, e. g., the aim is not the pedagogy of typewriting, but the psy-
chology of associations which enter into a thousand similar processes; to
an illustration of suggestion, by a realistic case of mental hedu%, the aim
is not to teach the art of mental healing, but the laws of suggestion which
operate in countless similar situations, and to vitalize and give relief to
a set of psychological facts in one coherent iUustration.
(B) Yet not psychology but to psychologize.
This does not mean that we should aim to make psychologists any
more than that a good &rst course in rhetoric should make a literary
artist or the first course in chemistry a chemist, nor does it mean that
the elementary student should be taught by the research method.
The primary aim is to train the student in the observation
and explanation of mental facts. Other aims are secondary,
such as:
1. Systematic knowledge of mental facts.
In some respects this may be coordinate with the primary aim but
there is great danger of mere nominal knowledge.
2. Culture: the ability to interpret life.
Ability in interpretation is the most fundamental element in culture;
with the knowledge of fact there must be the ability to judge for one's
self.
3. Efficiency: the ability to act effectively.
Efficiency and culture may be one ; the distinction is here made for the
purpose of emphasizing the two aspects.
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GENBRAL REPORT S3
4. Appreciation of mental life for itself, which is the basis
for the recc^nttion of its worth and manifold bearings.
"The world is different to me since I studied psychology, " is a charac-
teristic and proper remark of students.
5. A foundation for the philosophical studies.
The science of psychology furnishes the observable facts which con-
stitute a starting point for philosophy, logic, ethics, esthetics, etc.
6. A supplement to the material sciences.
Psychology is a study of tfae nature of the knower and the knowing
process — the mental half of animate life.
7. Applications.
The key to applied psychology b psychology.
The student does not really understand the mental process until he
comprehends it in some of its actual settings and uses.
(c) A little from each of all aspects of psychology and muck from
a few.
1. Give a balanced general survey of the fundamentals,
i.e., give a comprehensive bird's eye viewof the whole subject
with reference to content, point of view, relations, etc.
2. Give intensive illustrations of representative facts —
often choosing insignificant objects in order that the grasp
may be the more complete.
II. UETHOD.
(A) Secure action.
I. Keep the student doing things, instead of merely listen-
ing, reading, or seeing them done.
Fit the course to his capacity.
Make Mm feel responsible for every step that he takes.
Keep him working under pressure for accuracy and detail.
Make sure that he has the means for complying with every request.
Recognize results.
Even if he is to be entertained in the course, let it be most frequently
by his own activity.
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84 C. S. SEASBOKS
2. Let there be dramatic action in the progressive realiza-
tion of st^es in the course.
Use concrete tUustiations from the living present.
Show the meaning of each new process with reference to the whole.
Make sure that the student can follow the development
(B) Be systematic.
1. Keep a definite and detailed outline (printed or mimeo-
graphed)— of the whole course in the hands of each student.
This will aid in: (a) logical develc^ment, economy, and proper distri-
bution of empha^; (6) preparation and following, economically and
efifectively, a specific set of references; (c) the orientation of the student
so that he may see each day the relation of each new process to what has
gone before and what is to follow; {d) establishing confidence of the
student in the teacher and in himself; and (e), in short, bu^ess method
and mental economy.
2. Be reasonable and specific in all assignments and de-
mand results.
Set your task so that it may be performed when the assignment is made,
and so that you may have constant information about fidelity in work
and the que^ty of results. The sophomore is an elementary student
and psychology is necessarily somewhat abstract. Nearly every young
teacher makes the mistake of treating this elementary class by the
method of which he has become enamored as a graduate student. There
should be a radical difference in the methods of the elementary course
and following courses in psychology. It is absurd to treat the sophomore
in psychology as a research student.
Insist upon the mastering of difficulties. One of the greatest wastes
in college teaching is that we allow the student to shift when he encoun-
ters difficulty. Show him where the difficulty lies, spur him on, and
hold him to the task.
Place responsibihty.
3. Follow as far as possible the following order :
(a) From the simple to the complex; e. g., sensation, per-
ception, memory, thinking.
The principle, " from whole to part " is recognized only for the purpose
of orientation (see II. {A) 2, second note above) not for determiniag the
order of topics.
(&) From the known to the unknown; e. g., from the
common act of seeing, lead up to the attributes of sensation.
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GESRRAL XSPOST 85
(c) The course in the stream of thought; e. g., impression,
elaboration, expression.
(C) Use methods which develop efficiency in introspection,
observation, thinking and action.
Methods must, of course, be adapted to the instructor, the
equipment, the student, etc.; and all methods chosen must
be pursued with sufficient continuity to secure solid work.
Method without personal power is worthless. Among the
methods available for our purpose are the following:
1. The text book. Text books should be the source of
information and should be used very freely.
In the first yeai course of three hours, the student cannot afEord to
get along with less than three or four ordinary text books for his private
use, in addition to library sets to which he has access.
(It is veiy doubtful economy for a student to spend a year on one or
at most two text books, or to go on aimless himt in original sources before
he knows what he wants. Those "lecturers," who redte the contents of
the book to the students in order to save them the price of the book, are
too extravagant.)
The student can get more good in a course from extensive use of text
books than from more sped^zed reference work, because the text is pre-
pared specifically as an aid to the beginner. Limited reference work
should however, be encouraged.
(All teachers who cannot find good text books should at once publish
their own!)
We need a source-book to use as one of the texts.
The texts in a course should represent different points of view; e. g., the
functional, the structural, the experimental, the physiological, and the
genetic ; and the student should live in the atmosphere of different authors.
Ordinarily, the text books should not be used as a basis for oral recita-
tion; some other means of testing work must be found.
Nor should they be a constant object to be explained; let them be so
used that they help to explain the object under examination — perhai»
in the way we use an encyclopedia.
No matter what other means, such as lectures, experiments, discus-
sion, etc., are used in the class hour, we need text books with all of them;
the text book is or ought to be a most serviceable outline form of present-
ing the subject as a whole.
2. The lecture.
The lecture is one of the best means of personalizing the instruction,
yet it is one of the most .bused methods.
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86 C. S. SBASBOXB
(Hiere are three common sources of eirorio a teacher's evaluation of
the lecture method : (i) the warmth which the lecturer feels over having
made things dear: (3) the pleasure in freedom of expression and in hearing
himself, and (3) the failure to note that he has done the thinking so well
that the student gladly accepts his ready made portion without tUnking.)
In the elementary course in psychology the mere information lecture
should be tabooed.
Among the legitimate forms of lecture, for our purpose, are the follow-
ing:
\a) Hie organizing lecture.
This may occupy all or part of the hour and may answer the following
purposes: arousing in the student a point of view, interest, and ambition,
by setting up specific objects for search; outlining relations within the
work of the course; presenting supplementary ideas and concrete illus-
trations; and, first and last, to put Ufe into the course.
(b) The demonstration lecture.
The class demonstration is an economic method, when brief, to the
point, and systematically planned.
Do not make it an object in itself, but let the demonstration of a general
principle in a specific case be such that the student may see the general
principle and be able to make application of it in related cases.
(c) The special topic lecture.
This is the true "lecture" form; it may be set, finished and artistic.
These lectures give vital touch to the study by focusing attention upoa
some single aspect of mental life in the concrete; e. g., &e psydudogy (rf
piay, the formation of a habit, the psychology of writing, automatism,
the evolution of consciousness, the evolution of a moral instinct, the
meaning of infancy, fear, a case of alteration in personality, the psy-
dioiogy of Helen Keller, law in illusion, vantage groimds in the develc^
ment of i»ychology, etc. Such lectures illuminate the study of psy-
chology, arouse interest and give the student the genuine feeling that
there is more of it, and that it is all worth while.
3. Experiment.
(u) The individual experiment without a laboratory. (See Recom-
mendation (6) in Sec. VI of this report.)
This type of experiment enables the instructor to conduct work with
classes of any size, without expensive equipment, without laboratory
rooms, or much help. It saves the manifolding of equipment; frees the
student from technicalities incidental to the manipulation of apparatus
at a time when bis energies need to be conserved for the grasping of the
psychological problem; and saves time for the class periwi.
Secure the following conditions: (1) make the experiment intensive, —
"One thing well;" (2) use only such apparatus as may be at the disposal
of the student, or can be supplied freely .by the instructor; e. g., paper,
pins, cards, corks, watches, etc.; (3) supply full and specific directions
with the necessary preliminary statements for orientation ; and (4) follow
each set in the experiment with printed explanation, interpretation,
further suggestions, etc.
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GEJtERAl XBfOXT 8?
These experiments may be conducted both as class exercises and home
assignments; preferably, both combined.
They may be performed in the ordinary class room, provided the room
is equi[q)ed mtit movable desk chairs. It is good economy for the
instructor to provide for the whole class such material as may be needed.
{b) The class expenment. (See Recommendation a in Section VI)
of this report.
The d^ experiment should comply with the following three principles :
(i) every individual student shall take an active and responsible p^ in
the experiment; (a) the experiment shall be sufficiently intensive to make
it vital; and (3) each step m the experiment shall be explained and inter-
preted in print.
This is by far the most economical form of experiment, and psychology
lends itself peculiarly well to this mode of treatment.
(c) The laboratory experiment.
The laboratory experiment should be employed very conservatively,
if at all, in the elementary course, for the following reasons:
(i) The student is not ready for it. (We can begin physics with the
technical experiment, because in physics the apparatus is the one object
of experiment; but in the technical laboratory psychology, a student has
two objects, namely, the mental process and the apparatus to be manipu-
lated. He cannot do justice to both and is likely to lose himself in the
apparatus.)
(3) The tecbntcal laboratory experiment is worth while only to those
who are both amiable and willing to take psychology seriously. (Most
of the elementary students lack one or both of these qualifications.)
(3) Few, if any institutions, can supply adequate laboratory facili-
ties for elementary classes
4. Written exercises.
(o) The written review.
Spend about one-fourth of the study time in preparation for reviews.
Cramming is bad only when it is not done often enough.
One good plan is to give three or four questions a week in advance and
require the student to prepare an outline of what he proposes to write on
each of the topics. Make the tc^cs such that it will be necessary to
review all the work covered since the last review, and so as to make it
necessary for the student to organize the material for himself in some form
in which it has not been presented. On the review day, let each student
write one hour on one of the three questions, following his outline, and
hand in all of the outlines with the paper.
i_b) The written recitation.
The advantagesof the written recitation are: it encourages and secures
systematic analysis of the test by the student when he is at ease in his
room; it leaves the class-hour for lectures, demonstrations, experiments,
and (Uscussion; it secures full and specific recitation from every student
every day; it develops logical presentation.
It is erroneous to think that the outline written recitation requires
much writing. The best written redtatton requires much thinking and
very little writing.
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88 C. E. SEASEOKB
(c) Themes.
Let the theme be clearly distinguished from a report on some author
or book. Assign such topics as will favor a strictly psychological treat-
meat in terms of the student's own observation and thinking, and pre-
suppose assigned readings.
{a) Ten-minute tests.
These are an excellent substitute for the oral recitation if conducted
with rigidity.
5. Special exercises.
(a) Problems in introspection.
Introduce new topics by assigning, as a preliminary ezerdse, some
salient feature of the topic for introspection and report. Use the same
means to verify general statements.
These exercises may be small experiments, or they may be simple
unaided observations under specific instructions.
(b) Objective observation.
Set problems frequently in the objective observation of specific exprcs-
sions of mental life, mental laws, conditions, causal relations, etc
(c) Topical questions.
Prepare systematic and exhaustive questions as a basis for use as
references in daUy work, reviews, or even as a general skeleton or full sys-
tem of assignment of work in the course,
id) The topical outline.
This may be effective in the same way and for the same purposes as
the topical questions, and has the advantage of brevity.
(e) Discussion.
With the teacher who has the genius to handle it, this is one of the
most eSective methods of teaching in classes of not more than twenty-five;
but with the average teacher and the average class, it often becomes a
waste of time — an abuse of privilege. An undeserved approbrium rests
upon this method, because teachers who lack resourcefulness usually
fall back upon it. Incidental discussion should be strongly encouraged.
(J) The conference section.
Here is where discussion has its most valuable place; small sections
of the class meet with the instructor at regular intervals for that purpose.
All sorts of supplementary demonstrations and reports may be intro-
duced.
(f) Many other devices might be enumerated; such as reports on
supplementary reading, weekly "communications" on psychological
facts observed during tibe week, acting as observers in research under the
instructor or an advanced student, taking part in statistical tests, indi-
vidual conferences, etc.
111. PLACE m THE CURRICULUlf.
I. In the averse American college or university, the ele-
mentary course in psycholc^y should be taken in the sopho-
more year.
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CESRXAL KRPORT Sg
2. In the normal school it should be taken in the first year
after the high school.
3. The elementary course should run three hours through-
out the year, or five hours for one semester. (Or an equiva-
lent.)
AmoDK the reasons for this are the following:
(a) Psychology is a very laige subject. It is at least as large as
physics, chemistry, or mathematics. Yet, if a professor in a first class
institution should offer a one-semester three-hour course as the first
course in any of those subjects, it would be regarded with profound sus-
picion by an academic faculty. Psycholt^, when once established, will
come to the basis of a solid first course.
(b) Short couiaes are necessarily schematic, in rapid outline form,
and lacking in concrete illustrations and thorough experiments. The
difference between the long and the short course is not only in quantity,
but very essentially in quality.
Ordinarily, both professors and students apologize for the short course.
(c) Granted that the student should have a certain amount of psy-
chology, the instructor can plan that much better in one course than the
student can plan his work by choosing from elective semester courses.
(£) The short course represents an erroneous conception of the magni-
tude and worth of the subject.
(e) If the year is divided into two independent courses, students
seldom elect the second i whereas, if it is all in one, they are generally
pleased with it.
(/) AU courses after the elementary should be specialized; e.g. com-
parative psychology, technical laboratory course, social psychology, etc,
and the student needs a thorough foundation for these.
Wthin the coU^e course, there is no excuse for giving first a general
elementary course and later a general advanced course.
(The principal underlying the above arguments applies to the first
course in philosophy with equal force.)
4. The course should, if possible, be preceded by a course
in animal biology.
5. When the course is to be followed by some form of
applied psychology, it is all important that the applied psy-
chology, e. g., education or psychiatry, shall be built actually,
consistently, and unmistakably upon the elementary course
of psycholc^y as given.
To the disgrace of both the theoretical and the appUed courses it is
often said by students that they see no relation between them. This
correlation is a large problem in economy and efficiency.
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C. E. SEASHORE
IV. EQUIPMENT.
1. We must distinguish between the equipment for the
elementary course and the technical laboratory equipment;
the former may, however, often be drawn from the latter.
It should consist of:
(a) Apparatus for the demonstration experiments.
This should be large and portable, suitable for exhibition rather than
for fine work.
(b) Apparatus for the class e:q>eriment5.
This should be accurate, adequate, and under perfect control. Ibe
projection lantern may be used to advantage in several ei^riments of
this class,
(c) Supplies for distribution among the students in experiments which
require improvised material.
(d) Equipment for a few "q>edal topic" lectures which may be
experimental.
This is usually drawn from the technical laboratory course or the
research equipment.
(e) A full set of illustration material, such as physiological models,
charts, pictures, etc.
All the illustration material that can be reduced to charts should be
used in that way. Lantern slides should not be used when charts may
answer the purpose.
2. The elementary lecture room should be a well venti-
lated and well lighted hall furnished with movable desk
chairs, blackboards, chart cases, projection lantern, gas,
electric power, etc.
Students should be encouraged to work in this room when carrying
on experiments as outside assignments in order that they may get
inddental aid and supervision.
3. A smalt shop with simple equipment is essential.
4. The library should be equipped with sets of books to
which the whole class may be referred for certain chapters.
V. THE TEACHER.
I. The teacher of psychology, as compared with the
teachers of other college subjects, needs an exceptionally
thorough preparation.
The subject is usually taken up comparatively late. It is so large and
its interrelations are so coiiq>hcated that it takes a long time to acquire
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GENERAL KSPOKT
that knowledge about meatal facts, that ability in introspection, and
that technique in experimentatioD which is essential to the effective
Comparatively few, even of those who have completed three years of
specialized graduate study in psychology, are successful with the elemen-
tary class in psychology when they b^in. The elementary class seems
to demand a certain amount of apprenticeship. Institutions can well
afford to pay for the years of experience of a well trained psychologist.
2. Psychology is perhaps unequalled by other college
subjects in its power to influence the life of the student;
the introduction to this subject should, therefore, be taught
by mature members of the department.
Young instructors can handle advanced work better than the
elementary.
3. Pyschology perhaps su^ests more unsolved problems
than any other science; there is, therefore, a special demand
upon practical ingenuity and philosophical insight.
4. "The teacher is everything."
Id this there is a great truth. As we have learned to respect the indi>
viduatity of the pupil, we must learn to regard the individuality of the
teacher.
Aids, in the form of equipment, favorable support from the instituti<m,
knowl^lge about methods, etc., are always of minor importance
VI. SPECIAL RECOMUENDATIONS.
For furthering the advancement of the teaching of elemen-
tary psychology, the committee respectfully recommends the
following :
(a) Conferences of teachers with a common interest; e.g., state con-
ferences of teachers of psychology; east, south, central, and west con-
ferences on a larger scale; conferences of teachers of psychology in the
normal schools; conferences of the teachers of educational psychology
etc. Several such organizations exist.
(6) The appointment of a committee on the "Class Eqwriment."
(See n. C, 3, b, above.)
(c) The appcnntment of a conunittee on elementary experiments
without laboratory apparatus. (See U. C, 5, a, above.)
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NOTES ON THE DISCUSSION WHICH FOLLOWED
THE PRESENTATION OF THE REPORT.
By Helen D. Cook.
WilkiUy CoUtt*.
In the discussion which followed, Professor Pillsbury held
that the chief aim of the course should be not so much to
teach the student to psychologize as to teach him a body of
facts. (And Professor Seashore rejoined that without team-
ing to psychologize the student could never know the psychic
fact.) Professor Pillsbury dwelt also on the necessity of a
physiolc^ical basis for psychology. Professor Kirkpatrick
added that psychology should be a study not of consciousness
but of behavior.
Professor Thomdike reinforced the Committee's emphasis
on the necessity of assigning to the student questions for
preliminary study and concrete problems for solution, as
means by which to avoid a psycholc^y "which uses words
which nobody knows in order to state facts which everybody
knows. "
Professor Warren was unequivocally of the opinion that
psychology is not advantageously studied before the junior
year, whereas Professor Witmer recommended the teaching
of psychology even to freshmen and to high school classes.
Professor Witmer strongly ui^ed, also, a course extending
over at least two years.
With reference to normal school psychology, Professor
Monroe emphasized the importance in educational psychol-
ogy of biological material, urged the value of teachers' con-
ferences; and claimed that it is too early to attempt to stand-
ardize the normal school course. Dr. Rowe set forth the
difficulty of combining in one course the study of psychology
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NOTBS ON DISCUSSION „
with that of education. (Professor Seashore held that the
psychology in such a course should be taught from the point
of view of education.)
On the whole, all who took part in the discussion expressed
a very hearty approval of the report.
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THE
Psychological Monographs
EDITED BY
JAUE5 R. ANGELL, Ukiversitv or Chicago
HOWARD C. WARREN, Princeton Univsrsitv {Jndtxi
JOHN B, WATSON, Johns Hopkins UinvERSiry {Rmae) and
ARTHUR H. PIERCE, Smith College (BuUelin)
Some Mental Processes of the
Rhesus Monkey
BY
William Shepherd, Ph.D.
From the Pifchological Laboratory of the Geoige Wathiogton Ui
THE REVIEW PUBLISHING COMPANY
41 NORTH QUEEN ST., LANCASTER, PA-
AND BALTIMORE, MD.
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DiBiiizcdb, Google
Cover Read William T. Shepherd instead of William Shepherd.
Title page " " " " of " "
Page headings Read William T. Shepherd instead of William Shepherd.
Page III line 5 " 11 " of i. .
13 line 25 " not been " of been not.
37 " 28 " discriminate " of discrimination.
53 " 6 from bottom read experimenters instead of experiments.
46 " 16 read animal instead of animals.
50 " 34 " unanalyzed instead of analyzed.
53 " >9 " page 41 " of page 42-
58 " 36 " p. 45 5. " of p. 40 f!.
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Introduction*
Though one of the newest of the sciences, comparative
psychology, or, speaking more strictly, animal psychology,
may properiy claim as its father that acute observer and many-
sided Greek scientist and philosopher, Aristotle. The works
of this pioneer in science show him to have been an interested
and critical student of the mental, as well as the more strictly
zodlogical (morphological and physiological) side of animal
life, of which latter sciences (morphology and physiology)
he is the acknowledged father. His observations on the
comparative mental and moral traits of man and the lower
animals, so striking when we consider the data he had at
hand, may well entitle him to the credit of being the founder
of comparative psychology.
Within the past century, the evolution and anecdote
schools, represented preeminently by Darwin, Huxley, Rom-
anes, Lubbock and their co-laborers, have contributed largely
to this work and their observations and critical consid-
erations have thrown much light on the mental capabilities
of animals. These men, however, depended too much on a
method we now believe to be of little value in comparative
psycholc^y, viz., observation uncontrolled by experiment,
and their critical considerations have been colored because
they were interested chiefly in the theoretical, evolutionary
interpretation of their observations. This work, however,
has been invaluable in that the broader questions have been
set, and especially in that it has given great stimulus to the
study of the animal mind.
It has remained for the new, the conservative, experi-
mental, school of comparative psychology, to define more
> The animals used in this research were supplied by Prof. Shepherd Ivory Franz,
of the George Washington University, through a graDt to him from the Carnegie
Institution of Washington. Acknowledgment is, therefore, made to the Carnegie
Institution, without whose aid the work would not have been possible.
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2 WILLI A Af SHEPHERD.
accurately the problems of the science, and by more accur-
ate observations and by carefully controlled experiments to
solve those problems. To this more scientific and growing
body of workers, to Morgan and Hobhouse in England, to
Forel, Bethe and Hatchet-Suplet on the Continent, and to
Mills, Thomdike, Yerkes and Watson in America, must be
paid the highest tribute.
As results of the first part of the work of this newer school
distinct problems have been more precisely formulated by the
investigators. These problems may be divided into two
general classes, each of which may be resolved into a number
of concrete special problems. The first general problem is:
Do animals possess the lower mental powers that man pos-
sesses? Do they have the same fundamental psychic states
that man has; and, if so, how do these states differ qualita-
tively and quantitatively from those of man? To be more
concrete, we may ask: Do the lower animals discriminate
sensory qualities, do they discriminate brightness of lights,
do they discriminate colors or hues, noises, smells, and tactile
stimuli? Do they form and inhibit habits, do they retain
impressions and have the elements of memory? In what
way, if at all, do these differ from similar mental powers of
man? The second general problem is: Do the lower animals
have the so-called higher powers? Have they ideas, have
they the ability to learn by imitation, have they general
notions and reason? From any psychological considera-
tion we may omit the question of the presence of moral
judgments, a subject which is chiefly of ethical and religious
interest.
Despite both the newness and the difficulties of the prob-
lems and the imperfections of many of the present experi-
mental methods of study in this field, much work has been
accomplished and many valuable results have been obtained.
The results are, however, yet too few, and some of those of
more general interest have led to unsettled controversies.
Some of the results which at present may be considered
established are as follows: Some animals, the higher forms
at least, discriminate brightness values. Some classes of
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IKTRODUCTIOff. 3
animals discriminate pitch. All vertebrates and some in-
vertebrates show an ability to form habits of reaction to
stimuli, and they form at least simple associations. Animals
retain impressions and have a memory of some sort. Even
the most conservative and hypercritical have found this to
be the only satisfactory interpretation of the results of ex-
periments, and it is almost needless to say that the adherents
of the so-called anecdote school admit a high degree of mem-
ory in all mammalia.
The question on which comparative psychologists are
divided are as numerous as may be expected in a growing
science. Those of most interest in connection with the
present study may be briefly mentioned. Have animals
the same sensory equipment as man? Have animals <x>lor
vision? Or, do they merely appear to discriminate colors
because of differences in the brightness values of the stimuli
that are used? Do animals learn by inferential imitation?
Have the lower animals ideas or mental images?
In answer to these questions animal psychologists have
arrived at directly opposite conclusions, although alt the
recent investigators believe they follow the law of parsimony
enunciated by Lloyd Morgan. In regard to the so-called
higher mental powers, recent experimenters have taken a
less decided stand than formerly. They cease to deny to
animals reason, imitation and other similarly complex proc-
esses, but they say the case is not proven and demand
additional experiments and observations.
Among experimenters on animals Hobhouse is almost
alone in claiming that animals have true general notions.
It is true he does this after having made rather important
qualifications of the term 'idea.' The latter topic has, how-
ever, not been the subject of many experiments or, rather,
it has not been the subject of many reported experiments
and observations other than a few illy-controlled ones. The
question of the ability of animals to reason has been the
subject of numerous tests; but the casual observations of
the anecdote psychologists are the mainstay of those who
support the view that animals show ability to reason. Hob-
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4 WILLIAM SHEPHERD.
house has made some experiments which he believes indicate
some power or inference in monkeys and apes, but the obser-
vations that have been made by others of the group of
experimental animal psychologists are in the main of a de-
cidedly negative character. With the exception of Hob-
house, it may be said that the consensus of opinion is that
the presence in animals of this so-called higher faculty is not
proven.
These points we may summarize by saying that at present
comparative psychologists admit the possession by animals
of most of the lower powers of intelligence that man possesses.
Such powers of animals may, however, differ from those of
man quantitatively and in a qualitative manner. Possession
by animals of the so-called higher powers is an open question,
or set of questions, which have not been so widely studied, nor
so clearly determined ; and, respecting which the available
evidence points toward a negative answer in the form of a
verdict of 'Not proven."
On account of the ease of obtaining the domesticated
animals a large amount of the experimental work on animal
behavior has been performed upon cats, dogs and chicks.
On the other hand, the lower forms (invertebrates and non-
mammalian vertebrates) have been extensively studied in
respect to the simplest powers, such as tropisms. On account
of expense, difficulties of care and the apparent complexity
and variety of behavior, the higher mammalian types, especi-
ally anthropoids, have not been studied so consistently.
However, for studies in comparative psychology the value
of using primates instead of the lower vertebrates and inverte-
brates is almost self-evident. On the one hand, the anatomi-
cal similarities between man and the monkey are apparent.
Thereisthewell-known similarity between both their peripheral
and central nervous systems; and the similarity of arrange-
ment of muscles and bones, especially of the extremities,
must not be forgotten. Observations have made it evident
that there are also similarities in a physiological way. Move-
ments and reactions of an apparently human type are known
to be present in these higher forms, which are difficult if not
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INTRODUCTIOtr. J
impossible to observe in the lower forms. We may there-
fore expect from the careful studies of the mental states of
those animals, admitted to be immediately inferior to that
of man, more light on certain problems in the psychology
of human consciousness than from similar studies of others.
In making such a comparison of values it is not intended in
any way to detract from or to belittle the studies on the lower
forms. The value of experiments with the lower orders is
everywhere admitted. But at present it must also be ad-
mitted that the latter have received the attention of many
more writers, and their reactions have been subjected to a
much finer analysis.
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Experimental
The brief historical summary of comparative psychology
which we have given will, perhaps, appear as a sufBcient
justification for undertaking further study in the field; both
in regard to the lower and to the higher faculties in the animal
mind. This study of the psychology of monkeys was under-
taken, therefore, with a view to add to the knowledge we
now possess of the lower faculties in the animal mind, and if
possible, to throw some light upon the question of whether
or not monkeys possess some of the higher mental powers,
and also to limit or characterize any such higher powers, if
they should be found. The experiments have been much too
incomplete to be entirely satisfactory to me, and, in many
cases, the results are naturally lacking in definite conclusions,
though they yielded, to me at least, some valuable indica-
tions in the field. It must be said, however, that the unsatis-
factoriness and the indefiniteness are not peculiar to this
particular study, but that they apply to any work that is
performed in such a complex science. In certain of the later
experiments, it will be noted, definite conclusions have been
arrived at, and, had time permitted the carrying out of
further experiments, it seems probable that other tests might
have been concluded in as definite a way.
As tests of some of the so-called lower faculties of the
monkey's intelligence, experiments were made on brightness
discrimination, color discrimination, auditory discrimination,
the formation and inhibition of habits, and retentive power
(memory). In regard to the higher powers, observations
and experiments were made on learning by imitation, on
ideation, on reasoning, on adaptive intelligence and on
general notions. In brief, the chief aim of the study has
been, while profiting by the work of preceding investigators,
and with a steady adherence to the law of parsimony, to study
some of the lower powers of the animal mind, but especially
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EXPERIMENTAL. 7
by a modest study of the higher powers to seek for some
light, however little, on the subject of mental evolution.
Eleven monkeys were used in this work. All were Rhesus
(Macacus) obtained soon after their importation from India.
So far as we could ascertain .they were eight to nine months
old when received and, with the possible exception of monkey
2, they appeared to be without training of any kind. Monkey
I was a rather large, spare male, moderately active and bright
looking; in his work he showed only medium capacity;
when he could not perform an act and thus get food he showed
signs of anger, by jumping about and by shaking the wire
sides of the cage; he would sometimes jump at the experi-
menter and visitors who happened to be in the room, but it
must be remembered he was in a cage and could not get at
anyone; the movements he made were those of intimidation,
so often noticed in the Rhesus and other Macacque monkeys;
towards the end of the series of experiments he became
cross. Monkey 2 was a medium-sized male; moderately
active and of only ordinarily intelligent appearance; he
showed a mediocre capacity in work; not friendly; he wore
a collar about his neck when received and this would indicate
that he may have been accustomed to handling by sailors
or by others who previously owned him. Monkey 3 was a
small female, apparently the youngest of the eleven, very
active, alert; good-natured and friendly for a Rhesus; formed
associations the quickest of all the animals. Monkey 4
was a medium-sized male, not very active, but bright and
cunning looking; good-natured ; jumped at experimenter
half playfully; of medium capability in his work. Monkey
5 was a lai^e male, dull looking, not active; slow in learning
as compared with all theothers; he had a way of whining when
left alone; was rather ill-natured; would get angry when he
failed to do a required act, and thus fail to get food. Monkey
6 was a small female; bright and active; good-natured; very
cautious in all her work and actions. Monkey 7 was a Iar:ge
female; inactive, not very bright looking, but the most
friendly of the eleven animals; proved to be quick in forming
habits; very quiet. Monkey 8 was a lat^e male; he was the
Digilizcd by Google
8 WILLIAM SREPBERD.
master of the band ; of gruff appearance, domineering, active;
of not especially intelligent appearance; but was extremely
cautious, appeared to like to go through the tests. Monkey
9 was a medium large female; rather friendly; quick to form
habits. Monkey lo was a large female; not active; quite
friendly; fairly capable as indicated in the tests. Monkey
II was a large male; wise looking; quiet and friendly; some-
what timid; of medium capability.
Formation of habits.
Releasing fastenings: Since the appearance of Thomdike's
Animal Intelligence in 1898 the puzzle box method has been
a favorite one for comparative psychologists in studying the
formation of associations' by the mammalia. Partly as pre-
liminary to succeeding work on visual discrimination, an
experiment similar to those of Thorndike was made with
monkeys 1 , 2 and 3.
A box 2 feet long, 7 inches wide and 8 inches deep was made
with wooden slats and attached to one end of the cage in
which the three animals were kept. A solid wooden door,
6 by 4 inches, was arranged on each side of the inner or parti-
tion part of this box nearest to the cage. These doors had
vertical hinges and were kept shut by a turn button on the
side away from the animals. The hinged portions were 16
inches, the opening or button portions 8 inches apart. A
space was left on the sides of the doors next to the button
sufficiently wide to enable a monkey to put his hand through.
The doors opened inward into the feed box, i.e., outward
from the monkey cage. The food was usually so placed on
the floor of the food box that the animal could not see it,
except by going to the extreme right or left, depending upon
' The term 'association' as applied to the intelligence of animals has been loosely
used. Two principal usages are; (o) the animal's simple cerebraJ (or mental) processes
(merely anatomical, or it may be, physiological) such as is shown in a simple adjust-
ment to a stimulus, e.g,, in its learning to turn a button to open a door; {b) as eiplaio-
ing what are thought by some psychologists to be higher mental processes, «.{., idea-
tion or reasoning. When used in thb paper the word is to be understood to have a
connotation similar to the first meaning given above.
DiBiiizcdb, Google
RELEASING FASTENINGS. 9
the box into which the food was placed. In all experiments,
even in those in which no time is recorded in the paper, the
times for the performance of acts were taken by a stop watch
and recorded.
By reaching through the space or crack at the side of the
door and turning the button, the monkey could open the door
and secure the food which was placed in the food box behind
one of the doors. In the beginning of the work only one of
the doors was used ; when the association of turning the
button, i.e., of opening one door, was formed, both doors were
used. In the latter (two-door) preliminary experiments the
food was placed in a chance order behind one of the doors,
the animal not knowing which door that might be.
The records of the three animals used in this first experi-
ment are as follows: On the fourth day, after 32 trials,
monkey i gave evidence of the formation of the habit of
opening the door. Previous to this trial he had shown
many random movements, going from one part of the cage
to another, getting upon a bench in the cage, stopping all
work for a time, etc. On the fourth day, however, the habit
of going to the door directly was apparently formed, and the
method of opening was that of vigorously shaking the door
so that the button was gradually moved to permit the open-
ing of the door. On the fifth day, after 53 trials in all, he
began to fumble with the button in addition to shaking the
door. He continued to use both of these means with an
increasing tendency to rely on the button alone. On the
sixth day, after 95 trials in all, he had formed the association
of opening the doors by turning the buttons alone. His
average time for lo succeeding trials on this day was 3 seconds.
Monkey 2 formed the association of opening the door in much
the same manner as Monkey i. He pulled and shook it,
and on the third day, after 21 trials in all, manned to get
the trick of always opening it in this manner. On the fourth
day, after 51 trials in all, he began to turn the button in
addition to pulling and shaking the door. Also similarly
to the actions of Number l, he continued to use one or both
of the means, with an increasing tendency to turn the button
Digilizcd by Google
10 WILLIAM SBEPBERD.
alone. On the sixth day, after 102 trials, he always used the
button alone as the means of opening the door. His average
time for ten successive trials was 1.5 seconds. Number 3
on the second day, and after 1 1 trials in all, formed the asso-
ciation of 0F>ening the door by pulling and pressing it. On
the third day, after 34 trials in all, she began to turn the
button. On the fourth day, after 64 trials in all, she appeared
to have perfected the latter association and had inhibited
all tendency to use other means (e.g., shaking) for opening
the door. Her average time in the last 10 successive trials
on this day was approximtaely 1.5 seconds.
The method of learning in this experiment appeared to be
of the 'trial and error' type. As has been mentioned, the
animals scrambled about in a general way at first; they pulled
and bit at the door and the adjacent parts of the partition ;
shook the door violently; but, it is to be noted that after the
first few experiments the attention of the animal was always
directed to the door. Even after an accidental success in
turning the button, the association was not at once. set, but
only after a number of trials, with accidental successes many
times repeated, alternating, or rather interspersed, with many
errors. All the animals used in this work appeared, however,
to recognize a chance success and profited by it more quickly
than did raccoons under similar conditions. Another thing
of particular notice in their work, in which respect also they
differed from the raccoons, was their tendency to show signs
of anger when they could not open the door and get the
desired food. This was especially noticeable with Monkey i.
It is also of interest to note that when, preparatory to an-
other trial, I attempted to close the door after an animal
had opened the door and obtained food, the animal would
repeatedly attempt to hold the door open, as if the idea was
present that 'door- being-open' meant food. This reaction
is somewhat similar, I judge, to one observed by Thomdike
in his experiments with cats. It will be remembered this
author found a tendency on the part of the animals to walk
into the opened c^e from which they had just previously
escaped to obtain food. The action, on the other hand, may
be merely of the nature of a reflex.
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VISUAL DISCRIMISATION. II
Visual discrimination. It was formerly supposed, or rather
taken for granted, that animals possess the power of dis-
crimination of visual qualities, hues, and saturations. This
assumption was based upon observations of general be-
havior, of reactions to objects of different color, etc., but
in the past few years, however, comparative psychologists
have concluded that such power of discrimination could not
be assumed and they have sought by carefully controlled
experiments to test the truth of the matter. While the
experiments already made have yielded many valuable and
apparently positive results, several investigators, among
whom may be mentioned Yerkes (4) and Watson {2),
await more proof of such discrimination ability. The prob-
lem has been resolved into two questions. Is there a dis-
crimination by animals of brightnesses or intensities? Do
animals discriminate objects by their color or hue qualities?
In the work on visual discrimination to be recorded in this
paper nine monkeys were tested for color discrimination and
six for brightness (or intensity) discrimination.
Brightness Discrimination — Simultaneous Expos-
ures: Some ^tperiments on monkeys I, 2, and 3 were made
with the same apparatus that was employed in the prelimin-
ary experiments on the releasing of fastenings, with the addi-
tion of two cards, respectively black and white, which were
placed above the doors. The cards were 5 inches square,
and were placed above the doors. They were, therefore, 8
inches apart. A piece of food, usually a half or a whole pea-
nut was dropped in the food box; the black card was placed
above the door behind which the food had been placed, and
the white card above the other door. The monkey was to
open the door under the black card and obtain the food.
The food was placed in the compartments in an irregular
order, and the cards were correspondingly placed. At times
the food was not placed in the box until the door had been
opened by the animal, but often it was dropped in the box
immediately before or after the buttons were adjusted. In
this way it was possible to prevent the animal knowing whicii
door to open from the sight of food, and since raw peanuts
Digilizcd by Google
12 WILUAU SHEPHERD.
were used, the smell component, judging at least from human
ability to smell such food was at a minimum.
These experiments were begun December 4th and con-
tinued for eleven weeks. E^ch animal was given from 10
to 25 trials every second or third day. In some cases there
were longer intervals between the work periods. Each
animal was given a total of 1000 trials. At the end of the work
all were substantially perfect in opening the door under the
black card first. No animal was ever able to inhibit alto-
gether the tendency to open the door' under the white card
after the door under the black card had been opened and the
food had been secured. The average time for opening the
door under the black card in the last 25 trials for these three
monkeys was approximately one second. The curves of
learning, i.e., the time-experiment curves, correspond to
those found by almost all experimenters, but on account of
mistakes in opening the second door they cannot have much
value in this connection.
The fact that the animals formed the habit of opening the
door under black first would indicate that they discriminated
the cards. The quickness with which they finally performed
the act would also confirm this conclusion. Moreover their
looks and actions at the time appeared to indicate a knowledge
that the opened door meant food. When, for example, food
had been not placed in the box, after opening the door they
would look at me as if they expected their reward. The
closeness of the door buttons, and the great activity and
ready use of the hands, explain, I believe, the opening of the
second door so often. Furthermore, it was noted that while
after they had opened the door under the black card, they
appeared to expect food, when the door under white was
opened, their actions did not indicate that they expected to
be fed.
Brightness — Successive Exposures. For the tests with
monkeys 4, 5, and 6, I used a card displayer similar to that
used by Professor Cole and myself in brightness and color
tests made on raccoons. This was placed outside and about
6 inches from the animal cage. The accompanying figure
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VISUAL DISCRIMINATtOS. 13
is a diagram of the experimenter's view of this piece of ap-
paratus. (See Figure i.)
The front of the displayer was formed by a board 12 inches
high. A pin, 'P', on which two levers could be turned, was
inserted in a hole at the back and near the lower edge. On
this pin two displayers, 'W and 'B', were arranged so as to
be freely movable in the plane of the board. The two cards,
black and white, were placed at the upper end of the dis-
players so that the raising of the displayers showed the black
and white cards respectively. The card displayers were
i-inch thick so that there was a difference of i inch in the
distances of the cards from the animal box. On alternate
days, however, the cards were changed from the front to
the back lever, so the animals should not react merely to the
distance p>osition of a card. When the black was exhibited
the animal was to go upon a platform arranged inside the
cage and was fed, while he was not to go up at white and was
not fed. Usually and except at the stimulus, the animal sat
on a bench 12 inches from the floor and inside the cage.
He was, therefore, in a position to look down at the card
apparatus, for the upper portion of the card was about 5
inches below the horizontal level of his eyes. When the
black card was displayed and the monkey had climbed to the
food platform the experimenter rose from his seat and pre-
sented a piece of food to the animal. It is of interest to note,
therefore, that there was no possibility of the formation of
an association between the smell of food and food, rather
Digilizcd by Google
14 WILUAM SHEPHERD.
than between the appearance of the card and food. Since
the food was not placed near the cage or near the food plat-
form until the appropriate response was obtained the animal
had no smell stimulus for its guidance to an appropriate
reaction. ,
These experiments were begun February 5th and con-
tinued for a period of seven weeks. Each animal was given
from 10 to 25 trials daily, with intervals of two days, in some
cases of three or four days, during which intervals no work
was done with them on brightness. In all, each was given
700 trials. At the close of this work monkeys 4 and 6 ap-
peared to have the association perfected. The average times
for responding by going upon the platform when black was
displayed in the last 25 trials were 1.5 seconds for monkey 4
and 1.25 seconds for monkey 6. The tendency to climb to
the food platform when white was displayed appeared to be
entirely inhibited. Monkey 4 was, in this regard, perfect
in the last 25 trials, and monkey 6 responded to white only
once in the same number of trials. Moreover, at the time
of this mistake it was noted that in the trial (the 7th) in which
she responded to white, monkey 6 immediately came down
from the food platform with all the appearance of having
knowledge that she had made a mistake; she did not appear
to expect food and did not remain upon the platform for a
sufficient time to have food presented to her.
Monkey 5, at the end of the 700 tests, appeared to be
almost periect. In responding to black he made only one
error in the last 25 trials. His inhibition of the tendency to
respond to white was not quite periect, for during the same
series he responded to the white card three times. His
errors in this latter regard, however, were rather of the type
shown by monkey 6. He showed by his actions that he knew
he had made a mistake, for without waiting to be fed he
immediately returned from the food platform to the bench.
In the later experiments, and probably for some time
previous to the ones just mentioned, the movement of the
card displayer appeared to set up in the animals a tendency
to react, and the mistakes that were made on the last day
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VISUAL DISCRIMINATION. 1$
are, in my opinion, undoubtedly due to the lack of inhibition
of this reflex tendency to movement rather than to mistakes
in ability to discriminate.
For the next tests in this series small pieces (about one-
half inch cube) of white and rye bread were presented simul-
taneously on a board placed outside the cage but within reach
of the animal. The breads were prepared so that the taking
of one resulted in a punishment and in this way an
attempt was made to have the association formed quickly.
The rye bread was soaked in a solution of quinine bisulphate
(about I per cent, although no attempt was made to keep
the bitterness a constant factor). The white bread con-
tained no quinine and was presented in a comparatively
moist, fresh state, but much dryer than the rye bread that
had been soaked in the solution of quinine immediately before
the experiments. By taking the white bread and avoiding
the rye bread the animals were to show their ability to dis-
criminate these brightnesses.' In these experiments and in
later ones to be reported it was assumed that monkeys dis-
liked bitter tastes; this assumption, it will be noted, proved
to be true.
To obviate the objection that the smell of the quinine or
the rye bread might enable the animal to differentiate the
white from the rye bread, the two pieces of bread were placed
in varying positions on the board. At times they were placed
at equal distances from the front of the cage and within an
inch of each other. In other tests one was placed directly
in front of the other, and in other tests the positions were
irr^iularly varied, one being nearer, the other farther from
the cage. It might still be objected that the rye bread which
was wet from having been soaked in the solution of quinine
would give them a clue. That this objection was not met in
the conduct of the experiments must be admitted, but the
formation of the association, i.e., the positive reaction would
give evidence of sharp visual discrimination.
I In addition to its darfcer appeaiance, there was a hue differeace ia the lye bread.
Tbe latter, however, is the less prominent (actor.
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i6 WILLIAM SBBPSERD.
Nine animals were tested by this method, i, 2, 3, 4, 5, 6
7> 8 and 9. This plan of tests was very gratifying in its
results. It showed, apparently, complete discrimination
of the two pieces of bread. The rapidity with which the
habit of taking only the white bread was formed was striking.
This is especially noticeable when we compare the records
of the same monkeys in this and in the preceding brightness
tests. As table I shows, only from i to 14 trials were required
for each of the eight monkeys to establish the association.
This is excluding the work of monkey 9, which also dis-
criminated the white and rye bread, but which, being in the
same cage with monkey 8, could have seen the latter select
the white and reject the rye, and might be said to have learned
from or to have imitated monkey 8.
TABLE I.
™„„.
U^^n.T^
ToUlMiHiko.
Pint Day.
^.„.
9
1,1.1,40,5.6,8
1, M. 3, 4*, 66. 8i. 12a
i.ib,30,4a
13c 8
1 \
aTookrycbieadftCter having taken white, smelted or tasted, or both, and dropped
without eating.
b Took rye bread after having taken white, and ate both.
e first trial at second day; took rye bread but dropped it immediately without
smelling or tasting.
if Second trial of second day; without smelling or tasting.
It is of some interest to note the individual reactions to
the two stimuli that were presented. At the first trial each
animal took both pieces of bread, placed them in the mouth
and began to eat. In many cases the bitterness had a retard-
ing or inhibiting effect, for the animal would take the rye
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VISUAL DISCRIMINATION. 17
bread from the mouth, look at it, smell it, and then either
reject or reinsert it in the mouth.
Monkey I , in addition to eating the rye bread on the first
trial, took the piece of rye bread in the second trial, smelled,
tasted and dropped it. The bitter bread was not taken on
the third trial, but on the fourth the animal took first the white
which it ate, then the rye, which it also ate. The rye bread
was not taken on the next seven trials on that day. On the
twelfth test (the first test on the second day) the animal first
took the white bread and ate it, then took the rye bread and,
without smelling or tasting, dropped it immediately. On
this and on the following days all other tests were perfect in
that only the white bread was taken and the rye bread not
even handled, although, as has previously been noted, at
times the rye bread was placed closer to the cage than the
white bread.
Similar results were obtained with animals 2 and 3 as is
indicated in the table. The rapidity of learning is remark-
able in all animals, but particularly so in 4, 5, 6, 8 and 9.
In each of these animals two tests were sufficient to inhibit
altogether the tendency to take the darker bread. This find-
ing is so at variance with the results of comparable tests on
other animals that there would be ample opportunity to use
the results as an indication in monkeys of some form of
reasoning or of a marked activity to form pracdcal judgments.
Color discrimination — white and red. The same
general plan was followed as in the white and rye bread tests.
Rice, cooked to such a consistency as to be stiff, was, however,
used instead of bread. It was cut into small pieces of approxi-
mately the same size. Some of these pieces were used for the
white stimulus, and others when colored with Congo red for
the red. The red pieces were soaked in a quinine solution
and used while wet. The white contained no quinine and
was in a comparatively dry state. The precautions noted in
the previous test were taken to prevent an animal obtaining
a clue from either the relative positions or the smell of the
pieces of food.
The nine monkeys which had been used in the white and
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i8 WILUAM SHEPHERD.
rye bread experiments were tested in this experiment. The
rapid learning to take the white rice and to reject the red rice,
as in the white and rye bread test, was notable. From i to
3 trials were sufficient for the different animals to form the
association. Animal i took the red rice only the first trial,
and a similar result was obtained with monkeys 2, 4, 5, 6,
7, 8 and 9, Monkey 3 took the red rice only three times, on
the first, second and fifth trials. Not only is the rapidity
of the formation as striking here as in the case of the white
and rye bread, but the fact that all but one of the animals
formed the association, or, rather, inhibited the tendency to
take the red rice, after having experienced its effect only once,
may be taken as an indication of some form of reasoning.
Color discrimination — pink and green. A plan was
followed in the next test similar to that employed in the
white and red experiment. A smaller amount of coloring
matter was used and some of the rice was colored a light pink.
The pink rice also contained quinine. Another portion of
rice was colored green, and this portion containednoquinine.
The pink coloring was obtained, as has been said, by using
a weak solution of Congo red, the green was made by using
a solution of Malachite green. Both kinds of rice were used
while wet, and in this experiment, it is not probable that
discrimination could take place on account of difference in
the light reflecting qualities of the two kinds of rice. Care
was taken to have the two colors as nearly as possible of the
same approximate brightness. To this end the two colors
were mixed and compared to the colors pink and green of the
same approximate brightnesss on a color scale and the mixed
colors as well as those of the color scale were also tested by
the minimal perception method in a dark room to insure
their being of approximately the same relative brightness
{i.e., to the human eye).
In mixing the rice the coloring materials were not meas-
ured, nor was the relative amount in proportion to the water
of the solutions kept constant, nor the relative proportions
of the two colors to each other, nor to the amount of rice.
The color solutions were usually made up anew each day
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VISUAL DISCRIMINATION. I9
and there was inevitably a greater or less variation in satura-
tion and in brightness of the colors in different tests. These
remarks hold true in all the color tests. While criticism
may be made on any apparent discrimination on the basis
of hue under such conditions, to the writer discrimination
of color would be indicated by proper reaction from the very
fact of the variation of intensities. This will be pointed
out again in the discussion of the color experiments. As in
the preceding tests the same control precautions were taken
to prevent the animals from taking a cue either from the
position or from the smell of the rice,
In this test the monkeys formed the habit of taking the
green and rejecting the pink with even greater rapidity than
in the white-red test. Table II gives the records of nine
animals which were tested.
Color discrimination — pink and yellow. In this test
the same plan was followed as in the preceding experiments.
The pieces of pink rice contained quinine, while the yellow
contained no quinine. As in the preceding tests, both the
pink pieces and the yellow pieces were used while wet. The
pink coloring was produced by the same means as in the last
mentioned experiment, while the coloring of the yellow pieces
of rice was produced by the addition of lead chromate. The
test was controlled by the same means as in the pink-green
experiment to secure the same approximate degree of bright-
ness in the colors pink and yellow, and to prevent the animal
from receiving any cue from either the smell of the two
pieces of rice, or from their relative positions or relative dis-
tances. The same animals were used as in the preceding
tests, monkeys i, 2, 3, 4, 5, 6, 7, 8 and 9.
' The colors were mixed and compared to the colors pink, yellow, green of the same
approximate brightness on a color scale, and the mixed cobrs on the color scale tested
in a dark room tor quality o( brightness. Id the difFerent experiments, the pieces of
rice were also placed at varying distances from the animal to prevent his takinc a cut
dther from the smell or the positions of the two pieces.
Digilizcd by Google
D WILUAM SHEPHERD.
The following is the record for the animals for 25 trials each :
No. I took yellow in each triftl; took pink trial I
Color discrimination — pink, yellow and green. The
same method was employed in this experiment as in the
preceding ones. In this case the three colored pieces of
rice were simultaneously exposed. The pink and yellow
contained quinine, the green contained no quinine. The
TABLE n.
Discrimitutlioit of pink and iretn rice. T\oeiiSy experimentt o* tack animal.
»>«ns.
m.rArun.niAL..
»>».«»»«.
;
3
' 3
;
3
1
1
4
0
0
5
6
0
0
7
1, a. 3. 4. S
8, 9, 10, >
6,7.
14
13. 14, I
S. 16.
8
"
"
coloring for the pink, yellow and green was the same as used
in the preceding tests, each was used while wet. Exactly
the same means to control the tests were employed as above.
The same monkeys were tested as in the white and rye bread
test, the white-red, the pink-green, and the pink-yellow experi-
ments. Here again the rapidity of the rise of the habit of
response is striking. Table III gives the record of each
monkey for 25 trials.
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VISUAL DISCRIMINATION.
DiseritiUnaUoH of pint, yellev and green rice. Twtnty-Jm experiments tack animal.
Tern experiments first day, fifteen on second day. y, took yMm; p, took pink.
>on>il.
^^^r,^
lOTALIC^O.
ly.
1
'y.
I
ly,lly
»
ly
1
ly, «y.3y.4y,"yp,"y
6
»y. jy- 3y. 4y. sy. 6y.
II y. 13 y, lay. 14 y.
10
7
I y. a y. 3 y. ■« y. s y, 6 y. 7 y.
16
8y. 9y. 'oy. "y. "y.
13 y, 16 y, 17 y, 18 y.
8
»y- 1y.3y.4y, sy. 6y.
7y 11 y, liy, 13 y.
10
We see from the records and tables that the nine animals
quickly learned to select the rice that contained no quinine
and to leave the quinine rice alone. The learning to respond
quickly was much more rapid than, so far as I am aware,
that of any other monkeys which have been studied for
visual discrimination. In many cases, one trial was sufficient
to inhibit any tendency to take the quinine rice, and the
rapidity in inhibition of the wrong response was undoubtedly
due to the use of a punishment or to the association of a
disagreeable sensation, i.e., to the quinine in the rice.
Another factor in the rapid formation of the habit of
avoiding the quinine rice, in the case of pink in the pink-
green rest, was probably the knowledge or memory of dis-
agreeableness in red rice in the white-red test immediately
preceding. In the pink-yellow test and in the pink-yellow-
green test, knowledge of quinine in pink in the preceding
tests, was also probably a factor in their rapid discrimina-
tion. In the pink-yellow-green test the experience of the
preceding tests of pink-bitter, yellow-good, green-good helps
to explain the number of mistakes in yellow rice. But, with
all these allowances, we still have evidence of rapid formation
of the habits of selecting one color and of rejecting another,
and thereby apparently discriminating the colors red, pink.
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22 WILLIAU SHEPHERD.
yellow and green. That discrimination has taken place
cannot be doubted, but the question arises: did the animals
discriminate the colors as hues, or as merely brightness
values?
Watson (2), in very carefully controlled tests made on
three monkeys in 1908, failed to find evidence satisfactory
to him that his animals discriminated colors as hues. From
later tests (3) also, on monkeys, he is still not prepared to
affirm whether such discrimination is of color or of mere
brightness. Yerkes (4) , from the results of his well-controlled
experiments on the dancing-mouse, takes a view of the matter
similar to that of Watson. Both condemn the use of cards,
filters, etc., in experimenting on color discrimination. They
believe such methods are too loose to have much value
and they urge the use of more exact methods of determining
the matter.
In the experiments on cplor discrimination reported in
this paper, as has already been stated, the criticism that the
method used is a loose one may be urged. The exact propor-
tion of the different coloring materials to the bread or rice
and to the amount of water in making the solutions was not
determined. Furthermore, it may be said that as the color-
ing solutions were mixed anew almost daily, it would hardly
be possible not to have some variation in the intensities of
the colors at different times. This is true, notwithstanding
that means were taken to control the experiments, viz., com-
parison with certain color standards. Shall we infer that the
experiments were thereby so vitiated as to have little or no
value as a test of color discrimination? Such will doubtless
be the view of some, at least on first thought, but, to the
writer, these inaccuracies in method point to a different
conclusion.
It is admitted that the method and apparatus used in the
experiments herein reported appear loose and crude when
compared to the ingenious methods and complicated appara-
tus used in the experiments of Watson and others. It may
also be urged that my experiments take no adequate account
of the question of 'monochromatic bands' in the problem
,v Google
VISUAL DISCRJMINATWN. 23
of color vision. To this we may reply that in the ver>' loose-
ness and naturalness of the tests is to be found perhaps the
strongest evidence of the discrimination of color by the
animals which I tested. On the other hand I would point to
the highly artificial character of the methods used by some
experimenters. The complication of apparatus with its
reflectors, electric shocks and other appendages is artificial
in the extreme and and must result in an artificial attitude on
the part of the animal. The tests, with complicated appara-
tus, conducted in a dark room, bring about another artificial
and unusual situation, viz., the necessity for dark adaptation
by the animal. The method employed in these experiments
leaves to the animal a large amount of freedom and places
the animal in a position as natural as is possible in such work.
If, as has been urged by some, the experiments with colored
cards and filters may only mean that the animals react to
brightness or intensity, and not to hue relations, we should
expect an animal to react to a definite relation of brightness
unless we admit in animals some complex form of the feel-
ing of relation or a certain amount of inferential reasoning.
Such an explanation (t.e., brightness discrimination) may be
justified when the red-white test be considered alone. But
how may we explain the results in the pink-green test? Half
of the animals used in the latter test made no mistakes.
From the beginning of this experiment pink rice was avoided,
although it is not possible that the animals had any experi-
ence with red or pink rice previous to the time of these
experiments. Four of the animals, therefore, reacted prop-
erly to a hue of an intensity or brightness, considered
from the human standpoint, very different from that to which
the animals had learned to react. Do not these positive
reactions indicate rather clearly that somehow or in some way
the pink rice has been taken to be equivalent to or mean some
thing similar to red rice? Do not these results rather lead
to the conclusion that it is not a difference in brightness or
in intensity which has led to the appropriate adjustment,
but rather a difference in hue? Furthermore, the fact that
in the pink-green test the animals took the green and avoided
Digilizcd by Google
24 WILUAM SHEPHERD.
the pink regardless of the difference in the amount of color
is evidence that color as such was an important, and probably
the only, factor in the discrimination. This view receives
added weight from the similar results under similar condi-
tions (of approximate brightness and color) in the pink-
green-yellow tests.
It may, however, be urged that the carrying over of a
habit from a red to a pink indicates merely a dullness in dis-
crimination, that the red and pink may have been sensed or
perceived as approximate equivalents. It must be admitted
that this may be so, but the wide differences in the intensity
of the red and pink would indicate rather clearly that the
discrimination (or, compEirison, if you will) has been due not
to simple intensity relations but to hue or color similarities.
For the discussion of the results in the pink-green tests, we
may make two assumptions, that the two kinds of rice were
of equal or unequal brightness. If we assume an equal
brightness, the experiments must, it seems to me, be con-
sidered to show that discrimination has taken place because
of difference in hue. If we assume the two kinds of colored
rice to have been of unequal brightnesses, we must, remember-
ing the variations in the experiments on different days, con-
sider that the discrimination has taken place in spite of this
variation. The results then lead to the conclusion that the
discrimination has been due to a factor different to that of
intensity on the physical side, or that of brightness on the
mental. The only other factor which, in man, would pro-
duce such a reaction, is that of color.
A comparison of the results obtained in the different color
tests strengthens this view. The consideration of the results
in the white-red, pink-green and pink-yellow tests is instruc-
tive. Monkeys 4, 5 and 8 which had one experience in tast-
ing bitter red rice did not take the pink rice in the succeed-
ing tests. Now, it must be remembered that these monkeys
had no previous experience with pink rice, and their avoid-
ance of it can be accounted for only on the assumption that
something in the pink rice gave a clue to the animal.
The differences (to us humans, of course) between the red
Digilizcd by Google
VISUAL DISCRIUINATION 2$
and the white rice are three-fold: color, intensity, and, akin
to the latter, reflecting quality or sheen. The last named
was due to the differences in moisture, the red rice having
been soaked in the quinine solution only a few minutes before
the tests were begun. The sheen of the pink, green andyel-
low rice was the same, for all were equally moist at the time
of the experiments. There were, therefore, only two possible
differences between these colors, viz., hue and intensity.
If the avoidance of pink is to be explained, we must admit
that it was due either to hue or to intensity. If it were due
to a feeling of intensity difference, to an inference (taJfing the
human standpoint, of course) that darkness means bitter
and lightness means sweet we must account for a transfer
from the red (very dark) to the pink (slightly dark). We
must also account for the transfer in connection with the
other stimuli (green) which from tests was found to have an
approximate intensity equal to that of pink. So far as I
can see at present, the only possible intensity explanation
of this transfer is that red has a low brightness effect in com-
parison with other colors. However, we know that the inten-
sities of the red and the pink rice varied greatly from each
other, and we are forced to account for the phenomenon of
transfer on the basis of some quality not so markedly changed.
This, I believe, is the hue,
To sum up we may say that the evidence is in favor of the
conclusion that monkeys have the ability to discriminate
colors as such. So far as is known of the structure of the
retina and of the remainder of the visual apparatus there is
nothing to indicate any difference to the human mechanism,
and, from this point of view, no reason exists why the monkey
family may not be able to differentiate the four colors red,
green, yellow and blue. The rapidity of formation of the
association between the light bread and ^reeableness and
that between the dark bread (rye) and disagreeableness, as
evidenced by their selection of the former and their avoidance
of the latter, is indicative of sharp visual (brightness or
intensity) discrimination. The selection of one color and
the rejection of another in spite of differences in intensities
Digilizcd by Google
26 WILUAM SHEPHERD.
speaks strongly for the discrimination of hue. The transfer
of the habit from red to pink is indicative that the animals
had some form of feeling of relation or of similarity between
the colors as such, or that the hue (in itself and independent
of intensity) acted as the appropriate stimulus to inhibit the
tendency to take the particular food.
Auditory Discrimination — Noise. The apparatus used was
a wooden box 22 x 18 x 10 inches and a small board or slat
18 X 3} X f inches arranged to strike the box and thus make a
noise. One end of the board or slat was fastened to the top
of the box by a leather hinge. By raising the free epd of the
slat and suddenly letting it go, it struck the top of the box
and made a sound varying in loudness with the force with
which it struck. To give two sounds of different degrees
of intensity or loudness two small sticks, one 3 inches in
length, the other 5 inches in length, were separately used to
be placed perpendicular to the box and under the free end
of the board. By pressing slightly on the slat near the hinge,
and suddenly removing the shorter stick, the board would
strike the box and produce a noise of a noticeable intensity,
and by pressing on the board as before, and withdrawing the
larger stick that had been placed at the free end, the board
would strike the box and produce a much louder noise. The
same pressure, as nearly as possible, was exerted by the
experimenter on the board in both cases. By going upon
a platform arranged inside the cage when the louder noise
was made, the animals were to show their discrimination of
the louder and lesser noises. They were fed on the platform
when the louder noise was made, and were not fed when the
lesser noise was made. The noise apparatus was manipu-
lated near the closed side of the cage in which the monkeys
were kept. It was out of sight and it was not possible that
the reactions were made to stimuli other than the sounds.
The louder and lesser noises were made in an irr^ular order.
Three animals, 4, 5 and 6, were tested by this method.
Monkey 4 formed the habit of responding to the louder
sound and not to the lesser in eight days of 10 trials each,
i.e., 10 trials with each sound) or in 80 trials in all. In the
Digilizcd by Google
AUDITORy DISCmUINATION. J?
first day's trials he responded to the louder sound once in the
ID trials given him, and to the lesser sound twice in the same
number of trials. In lo trials on the eighth day he always
responded to the louder noise correctly and to the lesser
noise only once in the same number of trials. On the ninth
day he made no errors in the lo trials given him. Monkey
6 formed the association in eleven days of lo trials each.
On the first day she responded to the louder sound three times
and to the lesser four times. On the eleventh day she re-
sponded to the louder sound nine times and to the lesser
sound once. She made no erroi^ in the lo trials for each
sound on the twelfth day. In the time devoted to this work
with number 5, he did not form a perfect association. In
thirteen days' experiments of lO trials each he finally came
to respond to the loud sound in about 75 F>er cent of the trials.
His inhibition of response to the lesser sound was less perfect,
or about 50 per cent. Had the tests been continued it seems
likely he would have become perfect in discriminating the
two sounds. It is of some interest to note the apparent
inferior ability of 5 in comparison with 4 and 6 in this exjjeri-
ment. The work of 5 appeared typical of all his work re-
ported in this paper. Inhibition was apparently his weak
point, for he responded to no matter what form of stimulus.
The difference illustrates the individual variations in mental
capacity of the different animals.
Sound discrimination, Pitch. Kalischer (5, p. 204 ff.) has
reported experiments on sound discrimination with dogs,
which animals show an ability to discrimination pitch. Al-
though interested in the matter more from a physiological
than a psychological standpoint, he incidentally obtained
satisfactory evidence of discrimination of pitch by his animals.
His method was to sound a certain note on an organ or har-
monium as a sign that the animal should react in a certain
way, such as snapping at a piece of meat. When a different
note was sounded the dog was not to react and was not fed.
Selionyi using a form of the 'Pawlow method' on dogs has
also lately obtained evidence of discrimination by them of
the tones of an organ, organ pipes and of two whistles. He
Digilizcd by Google
28 WILUAM SHEPHERD.
also was chiefly interested in sound discrimination from a
physiological standpoint.
In experiments on auditory discrimination in raccoons
made by the present writer in 1906, reported by Cole (16,
p. 230) evidence of pitch discrimination by those animals
was obtained. In the experiments on pitch to be reported
in this paper I used the same plan that I had employed with
the raccoons, and which is similar to the method Kalischer
has used. An ordinary German mouth harp or harmonica
A was used. When I sounded the higher note, A 3, the
monkey was to go upon the platform used in the preceding
noise tests, and was fed there when the note was sounded.
When the lowest note, A i (two octaves lower), was sounded
he was not to go up and was not fed. The notes were sounded
in an irr^:ular order so the animal might not react in a rhythm
to the sounds. Care was taken to sound the notes with the
same degree of intensity, as nearly as possible. I took the
usual precautions that the animal should not obtain a cue
from my looks, motions or in any other manner, and react
to these stimuli rather than the tones.
The records for the different animals are as follows:
Monkey 4 formed the habit of responding to the high note,
A 3, and not responding to the low note, A i , in three days
tests of 10 trials each.' On the first day monkey 4 responded
to the high note six times in 10 trials, and not at all to the
low note. On the third day he responded to the high note
ten times and to the low note three times. On the fourth
day of the experiment (three days after the experiments just
noted) he responded to the high note ten times in 10 trials
and to the low note not at all in the same number of trials.
When tested on the fifth day, two days later, he was perfect
in 10 trials.
Monkey 6 formed the association in four days, in 40 trials
in all. On the first day she responded to the high note twice
in ten trials and to the low note not at all. On the fourth
day she responded to the high note nine times and to the
' i.e., ten trials of the high note and ten trials of the low DOtC.
Digilizcd by Google
INHIBITION OF HABIT. ag
low note once in lo trials of each note. In the lo trials on
the fifth day she was perfect.
Monkey 5 did not form the habit of correct response in
six days' tests of 10 trials each. In the 10 trials of high and
low pitch on the sixth day he responded to the high note six
times and to the low note only once.
If we may generalize from the work of the animals tested
in the above experiments we may conclude that Rhesus
monkeys discriminate quantitative differences in noises. They
also discriminate musical notes of widely different pitch.
These experiments also indicate that monkeys learn to dis-
criminate pitch with considerably more facility than do
raccoons in similar tests.
Inhibition of habit.
The activities or modes of behavior of animals, including
man, are of five kinds : (a) reflex actions; (b) instinctive actions ;
(c) habitual actions; (d) intelligent actions; (e) rational
actions. These different actions, in varying degrees, charac-
terize the different orders of animals. Generally speaking,
the lower the order of the animal the more the a form of
action is present, and the higher the order of the animal the
more the d and e forms of action are present. The lower
forms are, however, basal for man as well as for the amoeba.
Habitual actions are seen not only in the behavior of
animals of the higher orders but also in the activities of man.
Many apparently intelligent actions of man are of the nature
of habit. To say that habit dominates man's actions to a
very large degree, and reason to a very small degree is only
to state the simple truth.
Previous observations have indicated to comparative psy-
chologists that monkeys and other mammals have a marked
tendency to form habits of action. This was well shown
by Lloyd Mot^an and many others. A certain perceived
stimulus is followed by an agreeable or by a disagreeable
result, and an animal soon forms the habit of reacting in the
appropriate manner when the stimuli are given. The for-
Digilizcd by Google
30 WILUAU SBEPHERD.
mation of habits is, however, only one way of meeting the
conditions of the environment. Habits once acquired often
become useless, and sometimes have to be replaced by actions
opposite in character. In other words the inhibition or the
replacement of a habit is often necessary to the well being
of an animal or of man, and the ability to inhibit definite
modes of reaction, including reflex tendencies, is important
for advancement.
To test in some measure the ability of monkeys to inhibit
a recently formed habit four experiments weremade. Three
monkeys which had learned to discriminate white (normal)
from rye (quinine) bread were reviewed on this work daily
for seven days in order that the habit be firmly established.
A rest period of seven days was given, and then the memory
tested. The results of the latter test showed a perfect reten-
tion by all the animals. On the succeeding day each monkey
was presented with some pieces of rye bread that had not
been soaked in quinine. Then an experiment was performed
in which the rye bread was not made bitter. These tests
were continued for seven days, lo tests on each day. The
results are given in Table IV. It will be noticed that on the
first day monkeys 6 and 8 disregarded the rye bread, and
monkey 8 continued to disregard it for two more days.
Monkey 7 on the fourth trial on the first day took the white
bread first and then the rye. Five times thereafter she repeated
this, and the habit of refusing the rye bread when it was
simultaneously exposed with the white was broken. There-
after, on the six succeeding days of the experiment she left
the rye bread only once.
After this series a second test was made in which the
white bread was made bitter with quinine. Both pieces of
bread were presented simultaneously on a board, as in the
previous experiments. The results of the tests, 10 experi-
ments a day for seven days, are given in Table V. It will
be seen that the animals soon learned to avoid the bitter
bread. The mistake made by monkey 6 on the second day
was only a partial mistake for the animal picked up the white
bread, smelled it and immediately dropped it. The inhibi-
Digilizcd by Google
INHIBITION OP HABIT. 3I
tion in the case of monkey 7 was fixed on the first day after
four mistakes had been made.
A third series was then made in which the small pieces of
bread (white, bitter; rye, normal) were presented successively.
In these experiments the animal had a choice of taking or
of leaving the single piece, white or rye. The results are
given in Table VI. It will be seen that the three animals
avoided the white bread on the first day of the experiments,
but that 00 the second all took the white at least once. On
the second day monkey 6 took the white bread six times,
and monkey 8 four times. After these experiments both ani-
mals disregarded the white bread when it was presented to
them on the board, even though they were very hungry. Only
once during the remainder of these tests did monkey 6 touch
the white bread. On the fourth day, when the white bread
was presented, she put her hand through the wire of the cage
and swept the piece off the board.
The fourth series of experiments was begun after the
seven days of series 3. In this last series the breads were
presented to the animal by the experimenter, to see if the
inhibition effect, or the new habit of leaving the white bread
was associated with the presentation of the bread upon the
board outside the cage. Each piece of bread was taken by
the experimenter in his fingers and held just within the wire
netting of the cage. Even with this added inducement
monkey 6 refused to take the white bread, but both of the
other animals finally, and monkey 7 repeatedly, took it.
In the 70 trials with monkey 7, she took the white bread
fourteen times. At the sixth trial on the fifth day monkey
7 struck at me when I offered her the white bread, as if angry
that it should be presented to her. Monkey 8 took the white
bread twice on the second day, but after he had smelled it he
dropped it. On the fifth day he once reached toward the
white bread that was offered him, but drew back before he
had touched it. On the sixth day he struck at the white
bread or at me just as he had monkey 7 on the previous day.
These experiments show, on the part of the monkeys
investigated, a rapid inhibition of a previously formed habit,
Digilizcd by Google
32
WILUAU SBEPBERD.
and a rapid acquisition of a habit opposed to the original
habit. The acquisition of the new habit, however, took a
much longer time than that of the original habit, as can be
seen from a comparison of the results. In the later experi-
ments so many new factors, especially those of tempting the
animal by single presentations, were introduced that the
curves of learning cannot be directly compared. It would
be fair, however, to compare the results in Table V with those
in Table I. When this is done it is seen that the replacement
of the association is almost, if not equally, as rapid as the
formation. Should this result be true for other activities
of the monkey, it would indicate a rather high d^ree of
adaptivity, which goes far towards the production of appar-
ently intelligent actions.
Inhibilion of habils. All monitys had leamtd to moid quinint (ryt) bread; no quiiUiu
in eilkcr bread ft?r this test. W = took vkito, R — toot rye. Ten Ui^ tack animal
="..5-
.
.
. 1 , .
6
W lo
W 8
W 10
W lo
W lo
W lo
W to
R 0
R S
R lo
R lo
R 10
R lo
R lo
J
W 10
W lo
W lo
W lo
W lo
W 10
W lo
R S
R ID
R 10
R 9
R lo
R lo
R lo
g
W lo
W 10
W 10
W lo
W ro
W lo
W lo
R 0
R 0
R 0
R 8
R lo
R lo
Inkibilion ef habits. All monkeys had been practised on preceding tests (TabU IV).
Quinine in while bread, rye bread in natitral slate. Simultaneous presentation. K
took rye, W = took white bread. Ten trials daily.
■OHUTS AND
tWIMIMTl.
*
*
'
^
W I
W I'
W I
W 1
W lo'
W lo
W lo
6
R 10
R lo'
R 10
R 10
R lo*
R lo
R lo
W 4
W 0
W 0
W o
W o
W o
W 0
R lo
R 10
R lo
R ro
R lo
R lo
R lo
W 3
W I
W o
W o
W o
W o
W o
8
R lo
R lo
R 10
R lo
R 10
R ro
R lo
DiBiiizcdb, Google
IMITATION.
InUHlien of Habiti. All animali kad httn pretitnuly practiied on txperiments recorded
in Tables IV and V. Quinint in white bread, rye bread in natural slate. Sueces-
MM pretenlaliont. W = lack white, R — rook rye bread. Ten limes daily.
Momm An
(1U41D4W.
^
*
*
W I
W 6
W o
W o
W a
W o
W o
6
R xo
R lo
R lo
R lo
R lo
R lo
R !□
W o
W I
W 1
w s
W I
W 1
W 3
7
R lo
R lo
R lo
R lo
R lo
R lo
R lo
W o
W 4
W 0
W o
W o
W o
W 0
8
R lo
R lo
R lo
R lo
R lo
R lo
R lo
TABLE Vn.
Inkibition of Bahiis. All animals kad been prenously practised on experiments recorded
in Tables IV, V, and VI. Quinine in v>kile bread, rye bread in natural slate. Sue-
cetshe presentations tkroufk wire netting of cage inslead o/ outside. W •• look vhitt,
R " look rye bread. Ten trials daily.
MOnXra AMD
snUlMW.
'
*
*
'
W o
W o
W o
W 0
W o
W o
W o
6
R lo
R !□
R !□
R lo
R lo
R lo
R to
W o
W o
W 3
W s
W 7
W 3
W 4
7
R lo
R lo
R 10
R 10
R lo
R lo
R lo
W o
W 1
W I
W 9
W I
W o
W o
8
R lo
R 10
R 10
R lo
R lo
R 10
R lo
Imitalion.
Whether or not the higher animals learn by imitation is a
mooted question among comparative psychologists. Involv-
ing as it does the presence of ideation or of ' transferred
association' in the animal mtnd, it is of the utmost impor-
tance that this mental function be carefully considered.
Most experiments in the field of comparative psychology are
inclined to deny the higher forms of imitation to animals.
Morgan (7), Thomdike (8, 9) Yerkes (4), and Watson (10),
take this ground, while Kinnaman (11), Hobhouse (12),
Berry (13), Haggerty (14) and others believe they have
found evidence of imitation, apart from mimicry which is
Digilizcd by Google
34 WILUAM SHEPHERD.
sometimes spoken of as imitation and which may be considered
a reflex adaptation to certain stimuli.
It is necessary first to define precisely the term imitation
as it is applied in comparative psychoiogy. The term imita-
tion is used in a number of different senses. First it is used
as a synonym for what may be more accurately called instinc-
tive imitation. This is the form of imitation shown by all
animals in the performance of certain necessary acts, such as
that of a chick when it pecks at a bit of food on seeing
another chick do so. A second use of the word is in relation
to mass activities and we may therefore sp>eak of it as gre-
garious imitation. This form of imitation is the performance
of an act similar to that performed by another animal of a
herd or flock, the latter act being due to a definite stimulus
but the act of the imitator, although similar to that of the
imitatee, is not produced by this same stimulus but by the
stimulus of seeing or of hearing the first animal. This form
of imitation is illustrated by a herd of buffaloes running off
in alarm or a flock of sheep following their leader and jump-
ing over an imaginary obstacle. Lastly, there is inferential
or reflective imitation, where one individual sees another
perform an act, realizes or understands the consequences of
that act, and thereupon performs a similar act with the idea
of getting the same results.
Of the above forms of imitation the first two are of a low
order, and perhaps no comparative psychologist will deny
them to many of the higher animals below man. The con-
troversy, however, arises regarding the presence and the
amount of the higher form of imitation, the imitation that
has been defined as inferential. An attempt was made to
test the presence of this form of imitation, and three separate
kinds of tests were made.
An apparatus and plan similar to those already employed
by Hobhouse (12, chap, x), and by Watson (10, p. 175),
with which the former obtained positive and the latter nega-
tive results, were used by me in this work. This apparatus
consists of a glass tube or cylinder, 15 inches long and }-inch
in diameter, and a plunger of wood less in diameter but
Digilizcd by Google
IMITATION. 35
3 inches longer than the tube. The diameter of the wooden
plunger was such that it could be readily inserted in the tube
and was freely movable. A piece of food, usually banana or a
peanut, placed crosswise in the tube, was inserted in the
tube and pushed down about half way. A piece of food was
always selected sufficiently large not to drop through the
tube when the latter was held in a vertical position, and yet
sufficiently small that it could be readily displaced when the
plunger was used to push it through the tube. This appara-
tus was presented in turn to eight monkeys and the imita-
tion tests were begun after each had failed to manipulate
it three times. The tube and the stick were placed in
the cage with the animal to see if he could push out the food
after his attention had been attracted and he had been shown
by the experimenter how the stick was to be manipu-
lated for obtaining the banana or peanut. I endeavored co
have the monkeys see me perform the act at least three
times before each trial, and to this end I watched carefully
each animal while the exhibition was being given. If there
was in my mind any doubt that the animal had paid close
attention to the performance of the act by me, I repeated it.
Following the three demonstrations the animal was given
the apparatus for one minute, and this amount of time was
allowed him in which to perform the act. In the case of
some animals these tests were made daily and in the case
of others there were intervals of one or two days. The varia-
tion in the time routine did not appeju- to have any influence
upon the learning. The number of trials for each animal
was also variable, from 24 to 96, each having seen the act
performed three times before each trial, i.e., having seen the
act from 72 to 288 times.
All the monkeys failed to show any signs of imitation, and
I was unable to verify on these animals results like those
reported by Hobhouse. At the end of the tests all animals
acted in much the same way as at the beginning of the tests
and the first notes may be used to indicate the general charac-
ter of their activity. They bit at the food in the tube, locked
into the end of the tube at the banana, jerked the tube
Digilizcd by Google
36 WILUAU SBEPBERD.
around, often took up the stick and bit it; sometimes picked
up the stick and threw it away, dropped the tube, as if they
gave it up. While I was exhibiting the mechanism an
animal would watch the operation closely, and at the moment
the food appeared on the end of the tube within the cage, he
seized it. Sometimes they attempted to reach into the tube
to get the food. In this experiment I also tried Hobhouse's
plan of 'suggestion.' When an animal waswrestlingwith the
tube I pointed to and moved the stick towards him to call
his attention to it. Thereupon, sometimes, an animal took
up the stick, but only to throw it away after a few seconds.
In brief, throughout the three weeks of this experiment not
one of the animals appeared to show any understanding of
the problem, and any ability to cope with it. It may be
urged that a greater number of trials than 24, the number
some of the animals received, would have brought success
for some of them, but, were imitation o( this kind an impor-
tant and a constant condition In monkeys, this number of
trials would have been sufficient for them to demonstrate
its presence.
A second experiment on imitation was then performed.
This experiment was also similar to one made on monkeys
by Hobhouse (12, chap, x) and by Watson (10, pp. 173, 174)
A T-rake, consisting of a light handle 18 inches long, with a
cross piece 4 inches long nailed at one end, and at right angle
to the handle, was used. This was placed with the handle
end through the wire side of the cage and with the T-end
extending outward on the floor of the room. A piece of
banana or a peanut was placed on the floor outside the cage
but within the sweep of the rake when handled by an animal
inside the cage. In this experiment I wished to see if the
monkeys could grasp the situation of the use of the rake.
Two separate factors of adjustment enter into this; first,
the use of the rake for the use of grasping or reaching out
towards the food, and, secondly, the use of the implement to
draw the food nearer the cage and within reach of the hand
itself.
Monkeys i , 2, 3, 4, 5, 6, 7 and 8 were tested in this manner.
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IMITATION. 37
I showed an animal, by hooking the T around the food and
pushing the rake forward, but necessarily from the outside
of the cage, three times before each trial. I then let the
animal try the apparatus for two minutes. Each of the
eight animals was given from 24 to 120 trials in the four weeks
these experiments were continued. Each animal had failed
to use the rake three times, without being shown, before the
imitation tests were begun.
Monkeys i, 2, 4, 5, 6, 8, failed as completely as in the pre-
vious- experiment. Each seized the end of the rake handle
within the cage, jerked it around, bit it, tried to reach the
food with their hands through the wire of the cage. Some-
times they became angry and threw the rake aside; in some
cases they finally gave it up. I noted, however, that all soon
came to pull the rake into the cage, up to the T, which was
as far as the wire of the cage would permit. So far as I could
tell, each animal watched me closely while I was showing
them, appeared to have much interest in the proceedings, and
seized the food through the wire of the cage the moment it
was within reach. But what the six monkeys did not do was
to push the rake out and hook the cross piece around the
food. In all of the trials with these six monkeys so far as I
could see, none gave a sign of using the rake as a tool with
which to draw the food toward the cage. Here again it
may be urged that a greater number of trials than 24 should
have been given to all animals, but the simplicity of the
apparatus was such that in a child of the same age one or
two trials are sufHcient for a successful imitation.
After several days tests with two of the animals, 3 and 7,
there api)eared some evidence of imitation. Monkey 3
learned to push out the Take, and, with much slashing about
of the T end, would draw in the food. The securing of the
food by hooking the T around it was, however, very awkwEud
work for her. Sometimes she would knock the peanut away
in her effort to pull it in. On its being replaced by me she
usually succeeded in drawing it in roughly. The best that
can be said of her performance is that she appeared to learn to
imitate me perfectly in pushing the rake out, and awkwardly
in pulling the food in with the rake.
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38 WILLIAM SHEPHERD.
Following is an account of the tests on the third day. It
will be remembered that the method of securing the food by
the use of the rake was demonstrated three times before each
test. On this day, however, this demonstration was omitted
after the seventh test. Trial i was a failure; the animal did
not attempt to take hold of the rake after being shown three
times. On the second trial, however, after the three dem-
onstrations, the animal grasped the rake, and moved it
about in the direction of the food. She succeeded in bring-
ing in the nut sufficiently far so that she reached it and ate
it; time, 85 seconds. In this first successful attempt she
grasped the rake awkwardly and did not at first seem able
to manage it, but eventually she managed to swing it around
so that the nut was caught and, as has been said, pulled in
the nut so that she secured it by reaching through the bars
of the cage. In the next trial the movements of handling
the rake were about the same as those in the preceding trial,
although she had acquired some facility in the use of the tool,
and managed to secure the nut in 29 seconds. On the
fourth trial, during the demonstration she took hold of the
rake and pushed it outwards toward the food. After this
demonstration she pushed the rake outwards in an apparently
purposeful manner and secured the nut in 20 seconds. The
fifth trial was similar to the fourth, but with an increasing
ease in adjustment and with apparent greater facility in the
use of the rake. In 8 final trials on this day the demonstra-
tions were omitted but the actions of the animal were similar
to those mentioned in connection with the fourth and fifth
trials. On the sixth and tenth trials the manipulation of the
rake caused the nut to roll further away from the cage and
each time I replaced it. The times for these 8 trials were
respectively: 15, 15, 9, 12, 24, 14, 4 and 8 seconds.
Three days later, the fourth day of the tests, demonstra-
tions were given in the first and second tests. The results,
however, were similar to those on the third day, but with
shortened times for the performance of the act. The times
were as follows: 10, 8, 3, 4, 2, 6, 7, 9, 5, 4, 3, 9, 2, and 2 seconds.
On the seventh trial she managed to get the nut only part
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IMITATION. 39
way with the first puUing movement, but then, with apparent
intention, she gave another pull and brought the nut within
reach. On the thirteenth trial the nut rolled away when
touched with the rake but the animal pushed the rake out
farther beyond the nut and managed to secure it in the usual
way.
Monkey 7 had failed to show evidence of imitation on six
days of 3 trials each when I manipulated the rake and at-
tempted to exhibit the mechanism of securing food. It was
thought that the operation of another animal might be imi-
tated, and for this reason I placed her with monkey 3, which
at that time had learned to use the rake with facility. In
these experiments I carefully watched monkey 7 in order
to be reasonably certain that she observed monkey 3 perform
the act with the rake. Only after I was sure the animal
had been looking in the direction of monkey 3 while the latter
performed the act three times did I begin a test of monkey
7. At these times also I called attention to the tool by
pointing to it and to the food. In each trial she was per-
mitted two minutes to perform the imitation act, and if it
was not performed in that time I counted the test a failure.
The first five tests were failures, and likewise the seventh
and tenth. On the sixth trial she pushed the rake outwards
awkardly, but with such movements that she could not
secure the food. Finally, however, after 79 seconds, she
managed to hook the cross pieces about the food and immedi*
ately pulled it in. The eighth and ninth trials were simitar
to the sixth but the food was secured in 20 and 8 seconds
respectively. The tenth trial I have counted a failure, for
in this case the animal pushed out the rake and pulled it in
but did not manage to get the cross piece hooked around the
food. In the two minutes allowed for the performance of
the act, she did not manage to secure the food.
On the second day of these tests she failed to show by her
actions any evidence of imitation in the second, third, sixth,
ninth and tenth trials. Only ten seconds were required for
the proper performance of the act on the first trial, for she
immediately manipulated the rake so that it caught the nut
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40 WILUAU SHEPHERD.
and she pulled it inwards. The fourth, fifth and seventh
trials were similar, 12, 15 and 9 seconds respectively. Al-
though the eighth trial was counted a failure the monkey
did manipulate the rake properly, but in pushing it out-
wards the nut was hit and rolled farther way. In the final
trials of this day the animal did not make many efforts to
use the rake, although two minutes were allowed. In these
experiments the movements of pushing the rake outwards
were well performed, but those of pulling inwards were very
badly executed. This was also noted on the following day,
when in 6 trials, she manned to secure the food four times,
in 17, 9, II and 5 seconds. In subsequent trials she con-
tinued to be incoordinate in the pulling in movements, but
accurate in pushing out the rake.
It may be said that monkey 7 did not make the mental
connection between seeing me manipulate the rake and the
idea of the acquisition of food, but that some connection or
association was formed between seeing monkey 3 perform
the act and such an idea (or what corresponds to an idea in
the monkey mind). The impulse to handle the rake, to
manipulate it and to use it in connection with food may prop-
erly be said to be due to her having seen monkey 3 obtain
food by the use of this tool. This impulse or association
may be explained as A, ideal, or B, imitative. In the present
state of comparative psychology it is best to consider it the
latter, and we conclude that the use of the rake by monkey
7 has been due to an imitative impulse, the tendency to per-
form the same or a similar act performed by another.
In a third experiment to test the ability to imitate the
apparatus used in a previous test of analogical reasoning was
again employed. A piece of banana was suspended from a
pole that extended across the room. The food was placed
about 4 feet from the floor, high enough to be beyond the
reach of the animal when it stood upright on the floor. A
light pole, 9 feet long, 1.5 inches in diameter, was loosely
attached at one end by means of a pivot to a support and
extended 7 feet across the open space of the room to a hori-
zontal supporting board (C). which was 2.5 feet from the
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IMITATION. 41
floor. Figure 2 shows the arrangement. On the horizontal
board the free end of the pole was easily moved, and by
shifting it to the position P-X the pole was brought under
the suspended food. To bring about this change it was
necessary to move the free end of the pole about 3 feet, with
corresponding decreases in the amount of movement the
nearer to the pivot the pole was grasped. In the position
P-X the animal was able to reach the food if it climbed upon
the pole. The problem for the animal was to slide the free
end of the pole sufficiently far on the horizontal board or
Fig. 1. Diagnun of apparatus
pended banana; B, didiog pole i
to be moved in order tliat the an
slide, to bring the pole i
the pole and get the fooc
Monkey 3 had been 1
of experiments on anal
had failed to manipulai
shown how to manipuli
periments on imitation 1
animal I moved the p<
of P-X and permitted
time. After having bee
moving of the pole wa;
allowed two minutes in
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42 WILLIAM SHEPHERD.
act. If the act was not accomplished in that time I called
the test a failure and repeated the demonstrations. On the
first day of this experiment she succeeded in performing the
complex adjustment of pole, etc., four out of eight times.
On the first trial she moved the pole awkwardly, but suffi-
ciently far that she was able to reach the food; 30 seconds.
On the second trial she moved the pole only a trifle at first,
but returned to it and succeeded in moving it the required
distance; 25 seconds. On the next trial she changed the
movement of pushing to that of lifting the p>ole and pushing
at the same time. In this her movements were awkward
but she managed to get the food in 45 seconds. The next
three trials were counted as failures, although in all of them
the animal manipulated the pole and showed signs of recogni-
tion of the use to which the pole was to be put. On the fourth
trial after having moved the p>ole a short distance and not
obtaining food, she tried to get the food by going to the cross
piece from which the food was suspended. On the fifth
trial she pushed the pole off the slide, and could not get the
food. On the sixth trial she moved the pole a short distance,
and refused to complete the act. On the seventh trial she
moved the pole sufficiently far to obtain the food, 20 seconds;
but on the eighth trial she did not try to move the pole or to
obtain the food.
On the following day she was not shown how to manipu-
late the appEiratus the first three trials, two of which were
successful, but was shown on the other seven trials. At first
she pulled the pole part way, but it appeared to be difficult
work, and she obtained the food in 20 seconds. The second
trial she pulled the pole about 6 inches and stopped; I took
hold of the pole and helped her to move it a few inches, and
then she made a great effort and pulled the pole sufficiently
far to obtain the food. The third trial she did not attempt
to move the pole. The following seven trials were, it has
been mentioned, preceded by three demonstrations each.
In only the fourth trial did she take hold of the pole, at other
times she did not attempt any manipulation. On the third
day of the tests, six days following that just mentioned, she
Digi-izcclbyGOOgle
IMITATION. 43
failed to manipulate the apparatus in six trials, although she
was shown three times before each trial. Only once on this
day did she touch the poll. Two days later, she failed on
the first six trials. On the seventh she helped me to push
the pole when 1 was demonstrating it, and following this
she managed to get the pole moved by her own efforts in 68
seconds. On the eighth trial she moved the pole part way
and obtained the food in 30 seconds. The ninth trial was
a failure in two minutes. Seven days later she was given
three trials and was not shown how to manipulate the appara-
tus. She did not exhibit any signs of ability to manipulate
the apparatus and was then shown. The fourth trial was a
failure; on the fifth, she took hold of the pole at the time I
was moving it, and after the demonstrations she immediately
attempted to move the pole, which she managed in 36 seconds.
On the sixth trial she managed to get the food in 26 seconds.
The seventh trial, 18 seconds, and the eighth trial in 9 seconds
were successful. In the remaining 17 trials on this day
she gradually lowered the time for the performance of
the act although her actions were always about the same.
Two days later there were no failures in 20 trials, but the
actions of the animal in 2 of the trials were noteworthy.
In these trials the monkey moved the pole part way, then
stopped, and appeared to be observing the amount of the
movement and making a judgment r^arding the possibility
of reaching the food from the pole in the position in which
she had placed it. Then, not liking the position she moved
the pole farther and climbed upon it and obtained the food.
In these tests there was a gradual learning to eliminate
unnecessary movements and to perform the necessary move-
ments in a satisfactory manner. The experiment does not,
however, wholly belong to the type of learning of trial and
error, for, as has been remarked, the monkey moved the pole
properly the first time she attempted to do so. There was
no previous groping for a something, no fumbling with any-
thing but the pole. The attention, so far as shown in action
was directed to the pole. There was an immediate grasp
of the situation, and this coming after she had been shown
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44 WILUAU SBBPHERD.
that the food was to be reached by changing the position of
the pole is taken as evidence of imitation. The fact that in
later tests she failed to F>ay attention to the pwle and to
attempt to move it does not mean that she could not imitate,
but it is well known that the monkey is extremely variable in
its actions, and its attention is held with difficulty. We know
that in the production of habit, as many observers have
pointed out, there is not a gradual shortening of the time of
reaction as in the case of cats and dogs, but that the time for
the performance of an act is extremely variable. It is this
factor of variability due to elements such as lack of hunger,
etc., which seems to me to account for the lack of attention
to the problem. It is further to be noted that in the success-
ful trials she used a variety of means for the accomplishment
of the end; sometimes she pushed the ptole unhesitatingly
through the required distance; at times she pulled it, and at
times she pulled and pushed it. The variety of action indi-
cates that the performance of the act is not like that of a habit
formation, but that of attempting to accomplish an object
in any manner that this could be done. The performance
of the act was awkwEU'd, but there appeared to be imitation
of a relatively high order.
In the experiments that have been described evidence of
imitation by monkeys 3 and 7 was found in the second experi-
ment of the series. These two monkeys and the other mx
failed to show signs of imitation in the first experiment and I
failed to find any signs of imitation on the part of the six
monkeys in the second experiment. When these results are
combined, I think they indicate in a general way that some
monkeys may and do learn by imitation. The amount of
imitation is not shown, but the fact that in so many simple
experiments negative results were obtained indicates that
these animals do not imitate to the extent that has been
ascribed to them. We are, I believe, justified in concluding
that imitation is a mental funcdon of the monkey or of some
monkeys, although the results of my experiments may be
interpreted to mean that imitation does not play a very
important part in their learning process.
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Ideation.
The evolution and anecdote schools attribute ideation of
a comparatively high order to the animals with brains similar
to that of man, and they hold that ideas similar to those of
man play an important part in animal behavior. They base
this belief, however, upon uncontrolled observation and upon
flimsy and circumstantial evidence and not upon controlled
experiments and unequivocal facts. The evolutionists also
appear to believe it necessary to attribute ideas to animals,
else the doctrines of a progressive mental development would
not coincide with that of the physical development. On the
other hand, others, mainly experimenters, hold that the
casual observations do not indicate animal ideation and the
same facts are interpreted differently. Special tests have
given negative results and from these and from the careful
observation of animals in laboratory surroundings they con-
clude that animal ideation is not proven, and that the present
evidence tends to indicate an absence or a lack of ideas in
the animal mind. Some, however, are willing to admit that
animals may have ideas, although in small number, but are
forced to conclude that ideas are a very unimportant element
in minds below that of man. It is true that for the most
part the experiments of these men have not been special
tests for ideation, but tests for other reactions in which idea-
tion, if present, should or might have been exhibited.
Before passing to the evidence of ideation, it seems well
to dehne the term 'idea' and thus to have a precise notion
of what we should look for in animal behavior. For the pur-
pose of comparative psychology an idea may be dehned in
the following ways: a, an image or picture of a visual object
which is formed by the mind ; b, a general notion or concep-
tion; c, a plan or purpose of action or an intention; d, idea in
the sense of an understanding of a certain relation or situa-
tion (as of sensible objects). If, therefore, an animal ex-
hibits any of the mental conditions noted above we may
conclude that ideation is present.
A simple test for ideation was made with animals i, 2
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46 WILLIAM SHEPHERD.
and 3. A board 20 inches long and 3j-inches wide was
placed with one end against the side of the cage and within
reach of the animal with the other end extending outwards
from the cage and beyond reach. Food was placed at the
farther end. The object of the tests was to determine if an
animal would understand the situation and be able to secure
the food by the indirect method of pulling at the board near
the cage rather than by directing its efforts at the food or
the food end of the board which was beyond reach. In the
first trial monkey 3 after some testing of the openings of the
wire netting, seized the board awkwardly near the end with-
in reach, pulled the board alongside the cage and secured
the food, 30 seconds. In this trial the attention for only a
few seconds was directed to the food position but was directed
mainly to the end of the board that did not contain the food.
The actions of the animals in manipulating the board were
awkward but only in the method of reaching for and hand-
ling it. The actions were directed to the board, and not to
the food, and it appears that here is an example of an under-
standing of a situation, a direction of action to an end not- of
special interest in the situation. In the second and third
performances she duplicated her actions, but with shorter
times for its accomplishment because the awkwardness
largely disappeared and because the preliminary direction
of attention to the food was absent, 20 and 10 seconds. In
later tests she continued to react with complete success,
reducing the time to three seconds in the fifth trial, which
time includes that for the manipulation of the board and the
securing of the food. Monkey i succeeded in the third
trial but showed more misdirected efforts than did monkey
3. The third animal also managed to perform the necessary
acts to secure the food in the third trial, but the actions were
more awkward and poorly directed than those of monkeys
I and 3.
At the beginning of this test there were many unnecessary
movements on the part of each animal, but this awkward-
ness or lack of understanding of how to deal with the situa-
tion was mainly that of motor adjustment. It was a diffi-
Digilizcd by Google
culty in dealing with the board through the wire netting of
the cage and not a difficulty or a lack of understanding of
the problem, viz., of reaching for and of manipulating the
board. In the first trial of monkey 3 the animal directed
its attention to the board near the cage, and showed that
it appreciated the relation between this part of the board
and the securing of food. The later reduction in time for
the performance of the act, which at first sight makes the
experiment appear to be only another instance of learning
by trial and error, was mainly that of a proper adjustment
of arms and hands to the wire netting and not that of attack-
ing the board at the proper place.
These results indicate the presence of ideas of the above
described third or fourth class, i.e., a plan of action or an
understanding of a situation. It was apparent that from
the first the animal understood that the food could not be
reached directly but must be obtained by an indirect attack
on some other part of the apparatus. There was in this
case no general activity such as has been described by numer-
ous investigators in connection with the puzzle box experi-
ments; the trying here and the pulling there were notably
absent, and the attention of the animal was concentrated on
the board and on the getting the food. For a few seconds
after the board and food were displayed the hungry animai
would reach in vain for the food which was beyond its reach,
but this unsuccessful method was given up and the attack
directed to the board on which the food was placed. It is
also of great importance to note that the attack was directed
not to the part of the board on which the food was placed,
but to the part of the board away from the food.
The simplicity of the situation may be urged as an argu-
ment against the presence of ideation in solving the problem,
but I would again call attention to the ordinarily complex
character of similar experiments that have given negative
results to other observers. In such experiments we must
steer clear of both an absolute simplicity and of a complexity
abnormal to the animal. We must test the animal under
conditions which are within its mental range and which will
.yGoogle
48 WILLIAM SBEPBERD.
show the ability to reason. It is equally bad to set impossible
conditions and to draw unsupported conclusions, and in
both these ways comparative psycholt^sts have attempted
to solve the problem of animal reason and ideation. To
conclude, for example, that a dog or a monkey possesses
no power of ideation or of reasoning because it does not
thread a needle when the needle and thread are supplied
or because it does not unlock a door when the key is pre-
sented is to limit the terms ideation and reason to the
ability to perform certain activities connected with a certain
class of civilized man. The examples cited are^ perhaps,
extremes but they illustrate the attitude of a certain class
of experimentalists. On the other hand, to conclude that
a cat reasons because it attracts attention by scratching on
the window pane or because it manages to strike an electric
button for the opening of the door is to take no account of
the possibility of previous training of the nature of trial and
error. We should steer between the two extremes and test
the so-called higher powers of animals by presenting to them
conditions appropriate to the class. In the simple experi-
ment described in this section and in others to be described
in the section on reasoning (p. 52 ff.) the conditions are appro-
priate to the monkey family. We have presented to the
animal a new problem which it must solve, a set of condi-
tions to be dealt with in order that a resultant pleasure
(hunger satisfaction) ensue. In the solution of the problem
the animals took a direct path. There was none of the fum-
bling or groping, no trying here and there, no attempts upon
other parts of the c^e or its surroundings, but a direct
attack upon the boEird that held the food.
Somewhat similar actions were observed and noted above
in connection with the food box experiments. After the
previously ignorant (so far as the food box is concerned)
monkeys had been fed from the food box a few times so they
might become acquainted with the location of the food, the
doors were closed. Then began an attack upwn the doors,
not upon the wire netting of the sides of the cage. The
animals remained active about the doors of the food boxes;
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IDEATION. 49
they did not sit sulkily upon the platform in the cage; the
attention was directed to the doors of the food boxes. Thom-
dike indicates a belief that the attention of his cats was
directed to the string or to the button because the movement
in connection with these parts of the appliances was followed
by a pleasure. With ray monkeys, however, the attention
of the animals could not have been directed to the doors of
the food boxes on account of a pleasure in connection with a
movement, for the animals did not have to perform any
movements (except those of taking the food from the boxes)
in the neighborhood of the food boxes, and in connection with
the doors there were no movements to be performed. In
these cases there was no activity in the region of the food
boxes or of the doors which could become associated with a
pleasure. The attention must then be due to something
different from the movement-pleasure association; and it
seems probable that there is some form of ideation to account
for it.
In the brightness tests interesting behavior on the part of
monkey 3 was observed. As has been explained above, the
doors were opened by turning a button and thus food was
secured. After several days' experiments monkey 3 began
to close the door of her own accord instead of waiting for
me to close it preparatory to another trial. Before I could
close the door after she had opened it she would close it.
This would expedite the getting of food. It soon became
almost an habitual custom for her to close the door, and in
the remaining tests she did so from three to ten times each
day throughout the experiments. Why should an animal
close the door if it was not with some design or intention
(perhaps vague) of hurrying the food-getting process? It
seems too parsimonious and even inadequate to call this
kind of reaction a mere reflex. In the puzzle box experi-
ment the same animal and two others, monkeys I and 2,
often attempted to hold open the door with their hands and
this kind of action was recorded many times throughout the
series. At first I was inclined to consider this action as a
reflex but it is overworking the meaning of the term reflex
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so WILLIAM SHEPHERD.
to use it to explain or to describe the actions of the three
animals in this particular. Somewhat similar behavior in a
different situation was also noted with monkey 8. In test-
ing his color discrimination with colored rice and breads, the
food was placed on a block about a foot away from the cage
and then moved close to the cage so that he could readily
reach the food through the wire netting. When the food was
taken or rejected the block was moved backwards a short
distance preparatory to placing food upon it for another
trial. During the first few experiments he acted as most
of the monkeys do, viz., mov^ away from the side of the
cage as soon as the food was obtained. After he had learned
to discriminate the colors, however, it was noted that he
began to push the block away after having taken the appro-
priate food. This he continued to do during the remaining
trials on that day. The actions of monkey 8 in this case
had all the appearances of an understanding of the situation
and a desire to hurry the getting of food. It is of consider-
able importance in this connection to bear in mind that the
performance of this action was sudden and not a gradual
growth and not the result of trial and error.
The actions of the three animals in the situation of the
diagonally placed board, the actions of monkey 3 In closing
the door of the food box and the actions of monkey 8 in push-
ing away the block on which food was placed have a similar
appearance. Were we not obsessed by the law of parsimony
we would immediately say that these actions show the
presence of ideas in these animals, ideas of the highest form.
We are, however, in keeping with the law of parsimony, quite
justified in saying that the actions indicate the presence in
the minds of the animals of a something very much like an
idea in the human sense, a something that has for the animal
a function or a use similar to an idea in man. This 'some-
thing' may be crude and simple, and doubtless it is analyzed
by the animal, but it serves practical purposes. These
somethings may be termed, as does Hobhouse, practical
ideas; they may be partly sensory-motor reactions, and may
be partly instinctive, and in part they may be accounted for
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REASOtHNG. SI
by the superior equipment of the monkey in coordinated
vision and in the use of the hands. The evidence of the
ability to imitate supports the view of the presence of these
practical ideas, and in the section of this paper on adaptive
intelligence (p. 54 ff.) will be found additional evidence.
The fact that only a few of the animals exhibited anything
like the actions described, and each animal only a few, indi-
cates that these 'practical ideas' play a subordinate and unim-
portant rdle in the ordinary life of the animal, but they do
indicate that ideas may be present and have effect under
certain circumstances.
Reasoning.
It was formerly held that man alone possesses reasoning
power; other animals only instinct. Comparative psy-
chology has modified the older view of instinct, viz., that it
is a mysterious power, perfect at birth, unerring, unchangeable
in its working, and radically different from intelligence. It
has given the term a more precise definition by limiting it
in various ways, e.g., from reflex action and habit on the one
hand and the higher mental processes on the other. But
comparative psychology has not materially changed the
general view that reason is confined to man. And the
generally accepted position is that the observed actions of
animals may be explained as the results of simple associations.
Some experimentalists have found material facts that indi-
cate to them reasoning ability on the part of some animals,
but this conclusion is not accepted by others. Here again,
as in considering the subject of ideation, it is necessary to
define what we mean by the term reason. This word has
been used in a variety of ways and the following definitions
include the most important of the meanings that have been
given to the term. A, implied reasoning (Harris), e.g., my
recognition of yonder horse; B, inference from particular to
particular (James), e.g., the bird which finds bread upon the
window one morning comes back the next morning; C,
adaptive intelligence, the ability to adapt to our purposes
conditions more or less difficult and more or less unfamiliar;
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52 WILUAU SHEPBEXD.
D, analogical reasoning, whicli involves construction or
creation, e.g., to reacli an upper window I utilize a ladder
which I hnd; E, rational thinking (James); F, formal or
syllogistic reasoning.
That the higher mammals possess the ability to reason in
the first two senses, probably no comparative psychologist
will deny, although the explanation of the process may differ.
Implied reason is probably a function of all animals and the
ability to infer from particular to particular is well shown in all
the experiments in habit production. It is the higher level of
constructive analogical reasoning concerning which there is dis-
pute. Has the animal power to create or to construct? Hob-
house in some very interestingexperiments,c1aimsto have found
satisfactory evidence of the presence in animals of this class
of reasoning. He calls the mental states that lead to this
form of reasoning articulate ideas, and he has satisfied him-
self that these are present in some monkeys and apes.
With the purpose of confirming the work of Hobhouse I
made experiments on three monkeys which had been exten-
sively used in the previously described work on discrimina-
tion, etc., and with which I found it most easy to experiment.
The first experiment was one similar to the box and the
chair experiments of Hobhouse. Food was suspended by a
string from a long pole reaching across the room, too high
for the monkeys to reach or to grasp by standing or by jump-
ing. A light box was placed near the point of suspension,
but sufBciently far away that the animal could not reach
the food by standing upon the box. Only when the box was
moved and the animal climbed upon it could the food be
secured by the animal. Each of the three monkeys were
given three trials, in each of which five minutes were allowed
for the performance of the act. At the time the experiments
were made the animals were hungry and apparently each
watched me attentively when I fastened the piece of banana
to the end of the string and suspended it. When all had
been arranged the animal was permitted to approach the
food and to secure it if possible. The actions of the animals
were similar. Sometimes the animal tried to reach the food
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REASONING. S3
by jumping, sometimes after the unsuccessful attempts the
animal would have a puzzled look and finally gave up attempt-
ing to secure the food. None of the animals seemed to notice
the box and none made the attempt to use It as a means of
reaching the food. In their actions there was nothing that
I could interpret as a sign of deliberation or reflection, and
in this experiment I was unable to verify the results of Hob-
house. It is possible that the box appeared too heavy for
them to move, but I did not notice any indication that ithad
been observed, or rather observed in connection with the food.
That the box was not too heavy was shown by the fact that
a similar and equally heavy box was being constantly moved
by monkeys in a large adjoining cage. Failure to secure
evidence of reasoning in this experiment may have been due
to the fact that I did not continue the experiment so long as
did Hobhouse.
A second exp>eriment was then tried. This experiment
has been described in connection with the observations on
imitation, and the apparatus is illustrated on page 42, fig. 2.
The animal had to move a long pole, pivoted at one end,
under the suspended food in order to secure the food. In
all the experiments of this kind (three for each of the three
animals) there was no evidence of ability to grasp the situa-
tion and to solve the problem. In one trial an animal climbed
upon a cage which was near and jumped from it to the food.
In general, however, each animal made unsuccessful attempts,
most of them directed toward the food, and in each test
finally appeared to give up trying. Two months later one
of the animals (monkey 3) was again given three trials pre-
vious to the imitation tests and failed.
Adaptive intelligence.
Although no direct evidence of analogical reasoning was
obtained in the tests just described, other experiments on
reasoning gave interesting results. Those which are recorded
in this section deal with adaptive intelligence, the reason as
defined in the third class.
dbyGOCKj
54 WILUAM SHEPHERD.
A piece of twine was permitted to hang in front of and
12 inches away from the cage, beyond the reach of the
longest armed animal which was tested. At the end of the
twine a piece of banana was arranged ; a thin piece of wood
was pushed through the banana and turned so that one end
could be grasped by an animal in the c^e. By grasping and
pulling the stick inwards the food was secured. All the
animals were tested in this experiment. The results with
all except one of the animals were similar, and a description
of the actions of one will suffice to indicate the whole. As
scon as the banana and stick were arranged monkey 6 put
her arm through the wireof the cage, seized the end of the stick,
drew it toward her and secured the banana. This experi-
ment was repeated a number of times and in all there was a
similar immediate characteristic response. There appeared
to be a decided adaptation of means to end. No efforts
were wasted upon random movements. It did not appear
that any preliminary attempt was made to grasp or even to
reach for the food, but there was an immediate movement
toward the stick. The results for all animals are given in
table VIII, in which is shown the approximate time for the
performance of the act by each animal in each trial. The
absence of hesitation, the direction of the movement away
from the food and towards the stick, and the promptness with
which the food was secured speak for the presence of adaptive
intelligence in ten of the monkeys. It would seem that this
is almost always found in these animals.
In this test the results with monkey 5 were decidedly
different from those with the other animals, in that he failed in
the trials given htm. Monkeys i and 4 had considerable
difficulty in getting the food in the first and second tests,
but there was no gradual acquisition of the method of secur-
ing food with the other eight animals. The times for solving
the problem in the second and third tests were approximately
the same as those in the first tests for monkeys 2, 6 and 10,
and there was not much difference in the time between the
first and the later tests for monkeys 3, 7, 8, 9 and 1 1 . Much,
if not all, the difference in time can be accounted for by the
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better adjustment to the wire netting of the cage, the push-
ing of the hand through in the proper place, etc.
AiafUte tHldUioiee, suifeitdad food and aiek. Three or six trials each animal,
Timt tn stconds; / « faiUd.
™»i.A«. ! , ! .
.
5 e
1 60
■o
3
-
_
4
3
3
—
—
1 30
6
9
—
—
'"f
f.
_
_
_
6
7
4
3
,
,
,
3
4
3
3
3
9
3
3
3
4
3
A second test of the presence of adaptive intelligence was
made as follows: A light wooden lever B, 18.5 inches long
was attached by leather hinges at one end to a board A which
rested upon the floor The hinge of the lever was 4 inches
from the end of the horizontal board, well within reach of
the animals. The lever was inclined at an angle of approxi-
mately 45 degrees from the horizontal, and could be moved
forwards in a vertical plane. Fig. 3 illustrates the apparatus
in relation to the front of a cage. The apparatus was placed
outside a cage, the lower end of the lever being within, the
upper being beyond the reach of the animal. A piece of
banana or other food was placed at the farther end of the
lever, and the problem for the animal to solve was how to
secure the food which was beyond direct reach.
Eleven monkeys were tested with this apparatus, and all
with the exception of monkey 4 succeeded in the first test.
In the first test the animals usually took a longer time to get
the food, but as in the previous experiment this delay was
largely one of making the adjustment of hand to the proper
opening in the wire netting and not to attacking the apparatus
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56 WILLIAM SHEPHERD.
in the proper manner. In the case of monkey 4, he appeared
frightened at the time of the hrst trial and I showed him that
food was to be secured by moving the lever against the cage
and permitting him to secure the food. In the succeeding
trials he immediately attacked the lever and obtained the
food in the same manner as the other animals. Monkey 9
was in the same cage as monkey 8 when the latter wasbeing
tested and may have taken the opportunity to observe
monkey 8. That she performed the trick may have been
due to imitation, but I have credited her with having per-
formed it in the same way as the other animals. It is reason-
able to suppose that monkey 4 would have been able to
e iDtelligence C, leather hinges; B.,
manipulate the apparatus without being shown if sufficient
time had been allowed. However, in whichever way it be
conceived that the animal performed the trick we have a
mental something very much like imitation or like adaptive
intelligence. In many of the experiments the animals did
TABLE IX.
Aiaplitt intdUgaice, leter lesl. Time in seconds; / » failed.
'
,
9
4
i
t
6
4
3
3
^i
t
4
t
6
3
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REASONING. 57
not use both hands for the moving of the lever, but one hand
for the lever and the other for securing the food when the
upper part of the lever was within reach. Table IX gives
the time records of four monkeys in this experiment, those
for the other animals were approximately the same as those
noted in the table, although no accurate measurement by
watch was taken.
A third experiment was then made. A stick 22 inches
long, with I inch extending into the cage and the other out-
wards from the cage at a right angle, was arranged so that food
could be secured by drawing the stick lengthwise into the
cage. Ten monkeys were tested in this manner and all
immediately appeared to grasp the situation for they pulled
the stick and secured the food within three seconds. In
the cases when the food was dislodged the animals immedi-
ately gave up the stick and turned to the food, an indication
that the stick had been recognized as a means of obtaining
the food.
During the prc^ess of some experiments 1 noticed that
monkey 7 attempted at one time to pull toward his cage a
small tin bucket in which water was usually carried to the
animals which had been unintentionally left near the cage.
From this hint the following test was made with nine of the
animals. One end of a piece of twine, 1 yard long, was
attached to the bucket and the other end was left lying within
the cage. The bucket was placed at the length of the twine
away from the cage, and in it was placed a piece of food.
In all cases the animals seized the twine immediately, drew
the bucket toward the cage and seized the piece of banana.
Table X gives the times for monkeys 7 and 8. These times
are similar to those of the other animals.
TABLE X.
e inteUifenct, ptiUtHt bucket inwirds by n
: of twine. Time in leamda.
'■^ ■ I • ■ I • I ' • ' ' ' ' '•
7 643343I3433
S 033 3ij|j2J3
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58 WILUAM SHEPHERD.
A variation of the problem was then made. The end of
the piece of twine which had been left lying loosely within
the cage was tied to the wire netting 6 inches from the end,
leaving that amount of twine within the cage. In this test
the animal had to reach beyond the wire netting, seize the
twine and pull the bucket. Seven jmimjils were tested in
this way by an assistant, and the notes are not so full as I
could wish, but in brief the results are as follows:
average lor lo trials, 3 sec,
average for other 9 trials, 3,5 sec
average for other 9 triab, 3.5 sec.
average for 10 trials, 3 sec.
average for 10 trials, 1 sec.
average for 10 trials, z sec.
average for last 5 trials, 5.5 sec.
Monkey I, first trial, 3 sec.
Monkey z, first trial, 20 sec.
Monkey 3, first trial, losec.
Monkey 4, first trial, 5 sec.
Monkey 6, first trial, 4 sec.
Monkey 7, first trial 3 sec.
MonkcyS, first trial, izosec.
In the case of the animals whose actions were noted, each
pulled at the short free end of the twine at first, but soon
reached beyond the knot and pulled the bucket inwards.
This was done by some of the animals, notably monkey 8,
for four or five trials. The appreciation of the knot condi-
tion and the ability to deal with it is plainly shown by the
records given above.
The results of all the experiments described in this sec-
tion appear to speak for the possession by monkeys of adap*
tive intelligence, of a form of reasoning. The times for the
performance of the various acts are fairly conclusive, but in
addition the appearances of the animals, their actions, etc.,
especially during the first trial in each experiment indicated
an understanding of the problem. There was no fumbling
with the apparatus, no appearance of learning by trial and
error, but there was instjuit action following apparently
instant understanding of the situation. The reactions of
the monkeys in the situations provided for them gave diversi-
fied and relatively abundant indications of the presence of
practical ideas such as have been referred to in the section
of this paper dealing with ideation (p. 40 ff.).
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Memory.
No one questions the fact of the possession by animals of
a sort of memory for acts once or often repeated. Memory
in the restricted psychological sense, however, has been
denied to be present in animals but it is obviously difficult,
if not impossible, to determine this. The nature of reten-
tion and recall are matters that are disputed, but that animals
have an oi^anic memory, a physiological sort of memory,
is admitted. This memory acts well for practical purposes
and may therefore be called practical memory. Whether
or not this be merely organic, or whether or not animal
memory contains a representative factor must be left for
future investigation.
The monkeys observed in this study showed good ability
of recognition and retention, of the practical memory. After
the completion of the tests on visual and auditory discrimina-
tion no further exp)eriments were performed with the appara-
tus, until many of the later exp>eriments on imitation, ideation,
and reasoning were finished. Memory tests were then made
of the animals previously used in the discrimination tests
with the following results.
Visual discrimination of pink, yellow and green rice:
monkey i took the green ten times, took the pink the first
trial but only smelled it, and on the fourth trial took the
yellow after the green but dropped it almost immediately;
monkeys 2 and 8 took only green and paid no attention to
the pink and yellow rice; monkeys 3 and 7 took green each
trial, and in the first trial took pink after the green and smelled
but did not eat it. Auditory discrimination of noises after
thirteen days. Monkeys 4 and 6 made no mistakes in ten
trials each.
Lever test of adaptive intelligence. Monkey 6, after 130
days, showed perfect retention in four trials; monkeys 7 and
8, after 123 days, were also perfect in four trials.
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6o WILUAM SHEPHERD.
General Summary and Conclusions.
Monkeys learn to discriminate brightnesses, but take a
long time for this when the stimuli have not a direct relation
to the incentive for work; only a few trials are needed when
the visual qualities are a part of the objects to which they
naturally pay attention.
Colors are discriminated with accuracy and rapidity when
the colors are parts of the food (red, pink, yellow and green).
Three animals gave clear indications of the discrimination
of different degrees of notse, and also learned to discriminate
musical tones.
The habits are formed rapidly if there be the double incen-
tive of pleasant food as an inducement to a correct response,
and of an unpleasant stimulus to check a wrong response.
From the experiments recorded in this paper it appears
that monkeys learn to inhibit recently formed habits of
action with facility.
As far as the evidence goes, in regard to both the formation
and the inhibition of habits monkeys are superior to raccoons
and far superior to dogs, cats, elephants, otters and other
mammals which have been experimented with.
Monkeys have a practical memory; they appear to show a
good degree of retention; the representative function inmem-
ory is an unknown quantity.
Of the higher powers of mind the monkey has only rudi-
ments. He has a something which corresponds in function
to ideas of a low order and which serves practical purposes.
This something we call, with Hobhouse, practical ideas.
Two of the monkeys learned by imitation, but six others
gave no indication of imitation ability. It may be said that
while monkeys may leam by imitation to a limited extent,
imitation as involving ideation is a small factor in their
ordinary learning process.
All the tested animals appeared to reach a generalized mode
of action in dealing with problems but there seemed to be no
evidence of true general notions. They have an adaptive
intelligence, a lower form of reason, or a mental state inferior
to true reason.
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BIBUOGRAPEY. 6l
BiBLIOGBAPHY.
(i) Aristotle: Natural EUtory of Animals.
(s) WatsoD, J. B.: Some Experiments bearing upon Color Vision in
Monkeys. Journ. Camfar. Neurol, and Psychol., vol, 19, no. i, 1909.
(3) Watson, J. B.: Psychol. Bull., vol, 6, p. 395, 1909,
(4) Yerkes» R, M.: The Dancing Mouse. New York, 1907.
(5) Kaliscber, 0: Eine neue Hoqjrufungsmethode bet Hunden u. s.
w., Sitt. d. k. p. Akad. d. Wtss., vol. 10, Berlin 1907,
(6) Selionyi, G. P.: Contributions to the Study of the Reactions of the
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(9) Thomdike, E. L.: The Mental Life of the Monkeys. Psychol.
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(la) Hobhouse, L. T.: Mind in Evolution. London, 1901.
{13) Berry, C. S. : The Imitative Tendencies of White Riits. Journ.
Compar. Neurol, and Psychol., vol. 16, p. 333, 1906,
(14) Haggerty, M. E.: A Study of Imitation in Monkeys. Journ.
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(15) Wundt, ^ .: Lectures on Human and Anirrud Psychology. Trans.
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(16) Cole, L. W.: Concerning the Intelligence of Raccoons. Journ.
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