PART I.
PART I.
ASSOCIATION IN NORMAL SUBJECTS.Among the most striking and commonly observed manifestations of insanity are certain disorders of the flow of utterance which appear to be dependent upon a derangement of the psychical processes commonly termed association of ideas. These disorders have to some extent been made the subject of psychological experimentation, and the object of this investigation is to continue and extend the study of these phenomena by an application of the experimental method known as the association test.
§ 1. METHOD OF INVESTIGATION.
In this investigation we have followed a modified form of the method developed by Sommer,[1] the essential feature of which is the statistical treatment of results obtained by uniform technique from a large number of cases.
[Footnote 1: Diagnostik der Geisteskrankheiten, p. 112.]
The stimulus consists of a series of one hundred spoken words, to each of which the subject is directed to react by the first word which it makes him think of. In the selection of the stimulus words, sixty-six of which were taken from the list suggested by Sommer, we have taken care to avoid such words as are especially liable to call up personal experiences, and have so arranged the words as to separate any two which bear an obviously close relation to one another. After much preliminary experimentation we adopted the following list of words:
01 Table 02 Dark 03 Music 04 Sickness 05 Man 06 Deep 07 Soft 08 Eating 09 Mountain 10 House 11 Black 12 Mutton 13 Comfort 14 Hand 15 Short 16 Fruit 17 Butterfly 18 Smooth 19 Command 20 Chair 21 Sweet 22 Whistle 23 Woman 24 Cold 25 Slow 26 Wish 27 River 28 White 29 Beautiful 30 Window 31 Rough 32 Citizen 33 Foot 34 Spider 35 Needle 36 Red 37 Sleep 38 Anger 39 Carpet 40 Girl 41 High 42 Working 43 Sour 44 Earth 45 Trouble 46 Soldier 47 Cabbage 48 Hard 49 Eagle 50 Stomach
No attempt is made to secure uniformity of external conditions for the test; the aim has been rather to make it so simple as to render strictly experimental conditions unnecessary. The test may be made in any room that is reasonably free from distracting influences; the subject is seated with his back toward the experimenter, so that he cannot see the record; he is requested to respond to each stimulus word by one word, the first word that occurs to him other than the stimulus word itself, and on no account more than one word. If an untrained subject reacts by a sentence or phrase, a compound word, or a different grammatical form of the stimulus word, the reaction is left unrecorded, and the stimulus word is repeated at the close of the test.
In this investigation no account is taken of the reaction time. The reasons for this will be explained later.
The general plan has been first to apply the test to normal persons, so as to derive empirically a normal standard and to determine, if possible, the nature and limits of normal variation; and then to apply it to cases of various forms of insanity and to compare the results with the normal standard, with a view to determining the nature of pathological variation.
§ 2. THE NORMAL STANDARD.
In order to establish a standard which should fairly represent at least all the common types of association and which should show the extent of such variation as might be due to differences in sex, temperament, education, and environment, we have applied the test to over one thousand normal subjects.
Among these subjects were persons of both sexes and of ages ranging from eight years to over eighty years, persons following different occupations, possessing various degrees of mental capacity and education, and living in widely separated localities. Many were from Ireland, and some of these had but recently arrived in this country; others were from different parts of Europe, but all were able to speak English with at least fair fluency. Over two hundred of the subjects, including a few university professors and other highly practiced observers, were professional men and women or college students. About five hundred were employed in one or another of the New York State hospitals for the insane, either as nurses and attendants or as workers at various trades; the majority of these were persons of common school education, but the group includes also, on the one hand, a considerable number of high school graduates; and on the other hand, a few laborers who were almost or wholly illiterate. Nearly one hundred and fifty of the subjects were boys and girls of high school age, pupils of the Ethical Culture School, New York City. The remaining subjects form a miscellaneous group, consisting largely of clerks and farmers.
§ 3. THE FREQUENCY TABLES.
From the records obtained from these normal subjects, including in all 100,000 reactions, we have compiled a series of tables, one for each stimulus word, showing all the different reactions given by one thousand subjects in response to that stimulus word, and the frequency with which each reaction has occurred. [1] These tables will be found at the end of this paper.
[Footnote 1: A similar method of treating associations has been used by Cattell (Mind, Vol. XII, p. 68; Vol. XIV, p. 230), and more recently by Reinhold (Zeitschr. f. Psychol., Vol. LIV, p. 183), but for other purposes.]
With the exception of a few distinctive proper names, which are indicated by initials, we have followed the plan of introducing each word into the table exactly as it was found in the record. In the arrangement of the words in each table, we have placed together all the derivatives of a single root, regardless of the strict alphabetical order.[1]
[Footnote 1: It should be mentioned that we have discovered a few errors in these tables. Some of these were made in compiling them from the records, and were evidently due to the assistant's difficulty of reading a strange handwriting. Other errors have been found in the records themselves. Each of the stimulus words butter, tobacco and king appears from the tables to have been repeated by a subject as a reaction; such a reaction, had it occurred, would not have been accepted, and it is plain that the experimenter wrote the stimulus word in the space where the reaction word should have been written. Still other errors were due to the experimenter's failure to speak with sufficient distinctness when reading off the stimulus words; thus, the reaction barks in response to dark indicates that the stimulus word was probably understood as dog; and the reactions blue and color in response to bread indicate that the stimulus word was understood as red.]
The total number of different words elicited in response to any stimulus word is limited, varying from two hundred and eighty words in response to anger to seventy-two words in response to needle. Furthermore, for the great majority of subjects the limits are still narrower; to take a striking instance, in response to dark eight hundred subjects gave one or another of the following seven words: light, night, black, color, room, bright, gloomy; while only two hundred gave reactions other than these words; and only seventy subjects, out of the total number of one thousand, gave reactions which were not given by any other subject.
If any record obtained by this method be examined by referring to the frequency tables, the reactions contained in it will fall into two classes: the common reactions, those which are to be found in the tables, and the individual reactions, those which are not to be found in the tables. For the sake of accuracy, any reaction word which is not found in the table in its identical form, but which is a grammatical variant of a word found there, may be classed as
doubtful.
The value of any reaction may be expressed by the figure representing the percentage of subjects who gave it. Thus the reaction, table—chair, which was given by two hundred and sixty-seven out of the total of our one thousand subjects, possesses a value of 26.7 per cent. The significance of this value from the clinical standpoint will be discussed later.
§ 4. NORMAL ASSOCIATIONAL TENDENCIES
The normal subjects gave, on the average. 6.8 per cent of individual reactions, 1.5 per cent of doubtful ones, and 91.7 cent of common ones. The range of variation was rather wide, a considerable number of subjects giving no individual reactions at all, while a few gave over 30 per cent.[1]
[Footnote 1: In the study of the reactions furnished by our normal subjects it was possible to analyze the record of any subject only by removing it from the mass of material which forms our tables, and using as the standard of comparison the reactions of the remaining 999 subjects.]
In order to determine the influence of age, sex, and education upon the tendency to give reactions of various values, we have selected three groups of subjects for special study: (1) one hundred persons of collegiate or professional education; (2) one hundred persons of common school education, employed in one of the State hospitals as attendants, but not as trained nurses; and (3) seventy-eight children under sixteen years of age. The reactions given by these subjects have been classified according to frequency of occurrence into seven groups: (a) individual reactions (value 0); (b) doubtful reactions (value ±); (c) reactions given by one other person (value 0.1 per cent); (d) those given by from two to five others (value 0.2—0.5 per cent); (e) those given by from six to fifteen others (value 0.6-1.5 per cent); (f) those given by from sixteen to one hundred others (value 1.6—10.0 per cent); and (g) those given by more than one hundred others (value over 10.0 per cent). The averages obtained from these groups of subjects are shown in Table 1, and the figures for men and women are given separately.
TABLE I
Value of reaction 0 ± 0.1 0.2-0.5 0.6-1.5 1.6-10 >10
Sex Number % % % % % % %
of cases
Persons of M.. 60 9.2 1.8 5.2 9.7 11.0 27.8 85.5
collegiate F… 40 9.5 1.8 8.0 9.8 11.7 28.0 83.4
education Both 100 9.3 1.8 4.7 8.7 11.8 28.2 34.4
Persons of M.. 50 5.8 1.6 8.6 8.3 10.2 81.6 88.7
common school F.. 50 4.6 1.8 8.8 7.1 9.4 82.0 42.1
education Both 100 5.2 1.4 3.5 7.7 9.8 81.8 40.4
School children M… 33 5.9 0.8 4.2 8.7 10.0 28.6 88.5
under 16 Jr. F.. 45 5.0 1.0 4.6 9.8 11.0 80.1 36.7
years of age Both 78 5.7 1.4 4.6 9.8 11.2 29.4 87.4
General average. Both.1000 6.8 1.5
It will be observed that the proportion of individual reactions given by the subjects of collegiate education is slightly above the general average for all subjects, while that of each of the other classes is below the general average. In view, however, of the wide limits of variation, among the thousand subjects, these deviations from the general average are no larger than might quite possibly occur by chance, and the number of cases in each group is so small that the conclusion that education tends to increase the number of individual reactions would hardly be justified.
It will be observed also that this comparative study does not show any considerable differences corresponding to age or sex.
With regard to the type of reaction, it is possible to select groups of records which present more or less consistently one of the following special tendencies: (1) the tendency to react by contrasts; (2) the tendency to react by synonyms or other defining terms; and (3) the tendency to react by qualifying or specifying terms. How clearly the selected groups show these tendencies is indicated by Table II. The majority of records, however, present no such tendency in a consistent way; nor is there any evidence to show that these tendencies, when they occur, are to be regarded as manifestations of permanent mental characteristics, since they might quite possibly be due to a more or less accidental and transient associational direction. No further study has as yet been made of these tendencies, for the reason that they do not appear to possess any pathological significance.
TABLE II.
Special group values.
_____________________________________
Stimulus Reaction General Contrasting Defining Specifying
word. word. value. group 49 group 73 group 84
| subjects subjects subjects
|——- % No. % No. % No. %
chair……….. 26.7 25 51.0 11 15.1 10 11.9
1. Table….{ furniture……. 7.5 0 0 13 17.8 4 4.8
round……….. 1.0 1 2.0 0 0 4 4.5
wood………… 7.6 2 4.1 9 12.3 10 11.9
cotton………. 2.8 0 0 1 1.4 5 6.0
easy………… 3.4 0 0 8 11.0 1 1.2
feathers…….. 2.4 0 0 1 1.4 5 6.0
7. Soft…..{ hard………… 36.5 34 69.4 14 19.2 18 21.4
silk………… 1.0 0 0 0 0 2 2.4
sponge………. 2.2 0 0 0 0 4 4.8
cloth……….. 1.7 1 2.0 0 0 3 3.6
color……….. 12.9 0 0 20 27.4 6 7.1
11. Black…{ dress……….. 2.9 1 2.0 1 1.4 9 10.7
ink…………. 1.4 0 0 1 1.4 4 4.8
white……….. 33.9 31 63.3 17 23.3 18 21.4
desire………. 19.7 7 14.3 21 28.8 10 11.9
26. Wish….{ longing……… 1.9 1 2.0 6 8.2 2 2.4
money……….. 3.2 0 0 1 1.4 3 3.6
flowers……… 4.2 0 0 1 1.4 7 8.3
girl………… 2.4 0 0 0 0 5 0.0
29. Beau- homely………. 2.7 3 6.1 0 0 0 0
tiful..{ lovely………. 6.4 2 4.1 7 9.6 2 2.4
pleasing…….. 1.6 0 0 3 4.1 0 0
sky…………. 1.6 0 0 0 0 3 3.6
ugly………… 6.6 13 26.5 3 4.1 0 0
court……….. 6.4 2 4.1 5 6.8 10 11.9
56. Justice.{ injustice……. 2.6 6 12.2 1 1.4 0 0
right……….. 15.7 3 6.1 20 27.4 13 15.5
comfort……… 2.6 0 0 5 6.8 1 1.2
disease……… 0.9 2 4.1 0 0 1 1.2
59. Health..{ good………… 9.4 2 4.1 8 11.0 18 21.4
sickness…….. 15.3 23 46.9 6 8.2 1 1.2
strength…….. 11.2 2 4.1 12 16.4 4 4.8
arrow……….. 1.3 0 0 0 0 2 2.4
fast………… 22.2 0 0 25 34.2 15 17.9
horse……….. 2.8 1 2.0 1 1.4 6 7.1
65. Swift…{ quick……….. 11.7 1 2.0 22 30.1 2 2.4
run…………. 1.9 0 0 0 0 4 4.8
runner………. 1.3 0 0 0 0 1 1.2
slow………… 19.0 30 61.2 2 2.7 4 4.8
speed……….. 2.9 1 2.0 5 6.8 0 0
disagreeable…. 1.0 0 0 2 2.7 0 0
distasteful….. 1.0 0 0 4 5.5 0 0
gall………… 4.2 0 0 2 2.7 8 9.5
76. Bitter..{ medicine…….. 3.7 0 0 0 0 3 3.6
quinine……… 2.3 0 0 0 0 6 7.1
sweet……….. 30.5 31 63.3 8 11.0 12 14.3
taste……….. 6.6 1 2.0 17 23.3 3 3.6
bread……….. 20.6 17 34.7 4 5.5 18 21.4
eatable……… 1.2 0 0 9 12.3 0 0
81. Butter..{ food………… 6.3 1 2.0 14 19.2 3 3.6
sweet……….. 1.2 0 0 0 0 3 3.6
yellow………. 8.0 0 0 0 0 18 21.4
gladness…….. 4.4 0 0 7 9.6 1 1.2
grief……….. 1.8 4 8.2 0 0 0 0
86. Joy…..{ pleasure…….. 12.1 1 2.0 13 17.8 7 8.3
sadness……… 1.3 2 4.1 0 0 0 0
sorrow………. 13.5 23 46.9 2 2.7 2 2.4
§ 5. PRACTICAL CONSIDERATIONS.
This method is so simple that it requires but little training on the part of the experimenter, and but little co-operation on the part of the subject. It is not to be assumed that every reaction obtained by it is a true and immediate association to the corresponding stimulus word; but we have found it sufficient for the purpose of the test if the subject can be induced to give, in response to each stimulus word, any one word other than the stimulus word itself. No attempt is made to determine the exact degree of co-operation in any case.
In the early stages of this investigation the reaction time was regularly recorded. The results showed remarkable variations, among both normal and insane subjects. In a series of twenty-five tests, made more recently upon normal subjects, ninety reactions occupied more than ten seconds, and fifty-four of the stimulus words elicited a ten-second response from at least one subject.[1]
[Footnote 1: These tests were made by Dr. F. Lyman Wells, of the McLean Hospital, Waverley, Mass., and he has kindly furnished these data.]
It is noteworthy that these extremely long intervals occur in connection with reactions of widely differing values. That they are by no means limited to individual reactions is shown in Table III. by a group of selected reactions, all given by normal subjects.
TABLE III.
Word combination Reaction time Value of in seconds. reaction. comfort—happiness 20 5.0% short—long 11 27.9% smooth—plane 16 2.3% woman—lady 40 4.1% hard—iron 12 2.4% justice—judge 20 9.1% memory—thought 20 8.1% joy—pleasure 18 12.1%
It is apparent, even from a superficial examination of the material, that the factors which cause variations of reaction time, both in the normal state and in pathological states, are numerous and complex.
It has been the purpose of this study to establish as far as possible strictly objective criteria for distinguishing normal from abnormal associations, and for this reason we have made no attempt to determine by means of introspection the causes of variations of reaction time.
It would seem that the importance and magnitude of the problem of association time are such as to demand not merely a crude measurement of the gross reaction time in a large number of cases, but rather a special investigation by such exact methods as have been used by Cattell [1] and others in the analysis of the complex reaction. It would be impracticable for us to employ such methods in a study so extensive as this.
[Footnote 1: Mind, Vol. XI, 1886.]
In view of these considerations we discontinued the recording of the reaction time.
If the association test is to be useful in the study of pathological conditions, it is of great importance to have a reliable measure of the associational value of a pair of ideas. Many attempts have been made to modify and amplify the classical grouping of associations according to similarity, contrast, contiguity, and sequence, so as to make it serviceable in differentiating between normal and abnormal associations.
In this study we attempted to apply Aschaffenburg's [1] classification of reactions, but without success. Our failure to utilize this system of classification is assigned to the following considerations: (1) Distinctions between associations according to logical relations are extremely difficult to define; in many cases there is room for difference of opinion as to the proper place for an association, and thus the application of a logical scheme depends largely upon the personal equation of the observer; that even experienced observers cannot, in all cases, agree in placing an association is shown by Aschaffenburg's criticisms of the opinions of other observers on this point.[2] (2) Logical distinctions do not bring out clearly the differences between the reactions of normal subjects and those of insane subjects; logically, the reaction bath—ink, which was given by a patient, might be placed in the class with the reaction bath—water, although there is an obvious difference between the two reactions. (3) Many of the reactions given by insane subjects possess no obvious logical value whatever; but since any combination of ideas may represent a relationship, either real or imagined, it would be arbitrary to characterize such a reaction as incoherent.
[Footnote 1: Experimentelle Studien uber Association. Psychologische
Arbeiten, Vol. I, p. 209; Vol. II, p. 1; Vol. IV, p. 235.]
[Footnote 2: Loc. cit, Vol. 1, pp. 226-227.]
The criterion of values which is used in this study is an empirical one. As has already been explained (p. 8), every word contained in the frequency tables possesses a value of at least 0.1 per cent, and other words have a zero value. With the aid of our method the difficulty of classifying the reactions quoted above is obviated, as it is necessary only to refer to the table to find their proper values: the value of the reaction bath—water is 33.9 per cent, while that of the reaction bath—ink is 0.
Logically the combination health—wealth may be placed in any one of four classes, as follows:
/ intrinsic / causal dependence
health—wealth / \ coordination
\
\ extrinsic / speech reminiscence
\ sound similarity
But since our table shows this association to have an empirical value of 7.6 per cent, it becomes immaterial which of its logical relations is to be considered the strongest. It is mainly important, from our point of view, to separate reactions possessing an empirical value from those whose value is zero.
§ 6. AN EMPIRICAL PRINCIPLE OF NORMAL ASSOCIATION.
On a general survey of the whole mass of material which forms the basis of the first part of this study, we are led to observe that the one tendency which appears to be almost universal among normal persons is the tendency to give in response to any stimulus word one or another of a small group of common reactions.
It appears from the pathological material now on hand that this tendency is greatly weakened in some cases of mental disease. Many patients have given more than 50 per cent of individual reactions.
It should be mentioned that occasionally a presumably normal subject has given a record very similar to those obtained from patients, in respect to both the number and the nature of the individual reactions. A few subjects who gave peculiar reactions were known to possess significant eccentricities, and for this reason we excluded their records from the thousand records which furnished the basis for the frequency tables; we excluded also a few peculiar records obtained from subjects of whom nothing was known, on the ground that such records would serve only to make the tables more cumbersome, without adding anything to their practical value. The total number of records thus excluded was seventeen.
It will be apparent to anyone who examines the frequency tables that the reactions obtained from one thousand persons fall short of exhausting the normal associational possibilities of these stimulus words. The tables, however, have been found to be sufficiently inclusive for the practical purpose which they were intended to serve. Common reactions, whether given by a sane or an insane subject, may, in the vast majority of instances, safely be regarded as normal. As to individual reactions, they cannot all be regarded as abnormal, but they include nearly all those reactions which are worthy of special analysis in view of their possible pathological significance. What can be said further of individual reactions, whether normal or abnormal, will appear in the second part of this contribution.