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THE INFLUENCE OF AFFECTIVE FACTORS ON
THE MEASUREMENT OF INTELLIGENCE.
By C. A. RICHARDSON.
The first decades of the twentieth century have witnessed the rapid growth of two new developments in psychological science, namely the analytic method in psychotherapy and the testing and quantitative assessment of intelligence. The growths of these two movements have been curiously parallel in some respects; neither attracted any marked attention before 1900, each made immense strides during the war. While independent in origin and inception, both have now advanced to a stage at which we are compelled to consider whether each may not afford us information bearing on the theory and practice of the other.
Briefly, the kind of question that is now being asked is this: May it not be possible that the apparent intelligence of an individual is in part conditioned by affective inbibitions which conceal his real grade of intelligence? Is not a low grade intelligence due in some cases to the action of such inhibitions, and might it not therefore be possible, by analysis directed to the removal of the latter, to increase appreciably a person's mental efficiency?
So far as the measurement of intelligence is concerned, the practical issue to be decided is whether the performance of children and others in mental tests is affected by inhibitions of the kind referred to. Evidently this question could only be settled decisively by testing a number of children and then retesting them after analytic treatment. But, in the absence of such an interesting experiment, it is yet possible to arrive at a provisional, and probably reliable, conclusion, on the basis of considerations relating firstly to the nature of the tests themselves, and secondly to the results of the tests.
No doubt everyone would agree that, even when all disturbing factors are eliminated, children differ very considerably from one another in degree of intellectual capacity. It is unlikely that anyone would be prepared to maintain that, with sufficiently appropriate and complete psychotherapeutic treatment, all could be brought to the same level of intelligence. We may therefore assume that fundamental differences do exist. In other words, it is theoretically possible to rank individuals in order of intelligence. This implies that for each individual there is a numerical index, constant for that individual, which expresses his position in the hierarchy of intellect. Mental testing will therefore be directed to the discovery of that index, and the question we have to consider is whether such testing does in fact disclose the real index, or merely an apparent value of the latter modified by the influence of affective inhibitions which interfere with the subject's performance in the test. In what follows we shall exclude from our consideration definitely pathological cases, such as those manifesting epilepsy, hysteria, or dementia.
In discussing the effects on a child's performance which the tests exercise by their very nature, it is necessary to distinguish between general mental inefficiency and inability to pass certain specific tests which may be widely separated in the scale. Affective inhibitions, as opposed to natural dulness or defectiveness, are unlikely to produce general inefficiency unless they are so extreme in character as to verge upon the pathological. Accordingly the important point for our present purpose is the nature of specific tests; and here again we must distinguish between individual tests and group tests. We may leave the question of general inefficiency till we come to consider the results of the tests.
The majority of individual scales in use at present are based on the Binet scale or on one of the numerous revisions thereof. A glance through the questions in these scales will be sufficient to make it clear that by far the larger proportion of them are noticeably lacking in any element which might, for particular individuals, constitute affective or emotional tone in any degree worth considering. It is true that a few of the Binet tests deal with matters which tend to acquire for most persons come marked affective tone, but even in such cases the matters are of a kind calculated to produce far less emotional effect on children than on adults. But apart from these comparatively few and isolated instances the affective tone of the tests is almost entirely neutral.
The reason for this is not far to seek. Intelligence tests being directed to the discovery of the child's innate mental ability as opposed to his acquired knowledge, are so constructed as to call into play relatively fundamental elements in intelligent process. This results in a type of simplicity in marked contrast to the characteristics of ordinary educational tests and of those external conditions which in part determine the progress of the child in his everyday school work. It is a simplicity consisting in a lack of complication by widespread and elaborated associations which, by their assimilation to the matter in question, may give to the latter a very marked emotional tone, and hence lead to affective inhibition where it is concerned. Doubtless this accounts for the fact that some children who do well in an intelligence test may be making progress in school at a slower rate than their success in the test would lead one to expect. These considerations reveal a merit of the intelligence test which makes it one of the children's safeguards. The writer numbers among his own cases examples both of specific and of general inefficiency in school work which investigation showed clearly to be due to causes of an affective character. Yet the intelligence test penetrated these inhibitions and revealed the true grade of mental capacity to be superior to that manifested in school.
In addition to the inherent nature of the tests themselves, it is necessary to consider for a moment the conditions of their administration. The individual tests are given to one child at a time, and, in general, no one else is present but the examiner. Evidently, such conditions may in certain circumstances, and with children of certain temperaments, be conducive to the setting up of inhibitions. The removal or prevention of inhibitions arising in this way depends for its success almost entirely on experience in the general technique of administering the tests; and the skilled tester (who, it need hardly be said, should be a sufficiently trained psychologist) will quickly recognise symptoms indicating the presence of inhibitions and will know how to deal with the latter. It may safely be said that, with a tester who understands his work, any serious effect due to affective inhibitions arising from the conditions of administration of the tests can be practically eliminated.
When we turn to consider group tests, however, the case is somewhat different. It is true that, among the large number of items which go to make up a group test, there may perhaps be a few which possess marked affective tone for certain children. There seems no reason to suppose that the effect of this, if it exist at all, will be more than slight; and, in any case, the very multitude and variety of the items is likely to ensure that any affective consequences will average out among the different children so as to leave unaffected the reliability of the norms of performance as a basis of comparison.
More serious, however, in the case of group tests, are the possible effects of the conditions of administration. In the majority of group scales the separate tests are given out at intervals, each, after brief verbal instructions from the examiner, being carried out under a strict time limit. The possible effect on certain types of child (e.g. the 'nervous' or 'anxious,' or even 'cautious' child) of this state of affairs can easily be imagined, and the conditions of the test necessarily render it impossible for the examiner to eliminate disturbing factors by dealing with the children individually. It does not seem possible to get rid altogether of the influence of such factors in a group test; yet, on the other hand, the results of the tests show that the mass effects produced by the disturbing elements are negligible, though, of course, injustice may be done to individual children. In the case of individuals, the effects are probably reduced to a minimum in those scales in which the tests are not timed separately but only as a whole, the child being left to work quietly through the questions by himself, without interruptions at intervals by the examiner1
It will be clear, then, that an examination of the tests themselves reveals but little in their nature to warrant the conclusion that affective factors may frequently militate to a serious extent against a child's performance. But evidence of a more definite, and therefore more decisive, nature is found to be available when we turn to a scrutiny of the results of the tests. In considering these results we should expect to find the influence, if any, not only of specific inabilities with regard to particular tests arising from specific inhibitions, but also of general inefficiency due to affective factors of a more far-reaching type.
It was pointed out at the beginning of this paper that, when disturbing elements are eliminated, individuals will differ in their respective grades of mental capacity, intelligence tests being directed to the discovery of the index, constant for a given individual, which expresses his particular grade of intelligence. A child's degree of intellectual maturity is expressed as a 'mental age. As intelligence develops with increasing age, so will the mental age increase. But the child's intellectual rank can only be expressed by comparing him with the average' child, and the result of this comparison is termed the 'mental ratio' (i.e. the ratio of the child's mental age to his actual age) or 'intelligence quotient' (I.Q.). There now arises the question whether the I.Q. can be taken as that constant index which denotes the child's grade of intelligence.
Let us suppose that the influence of affective inhibitions frequently and markedly interferes with children's performances in the tests. How could this be detected in the results of the tests? Evidently by retesting the same children after various intervals of time, some of the intervals being of considerable duration. We should then expect to find that the results of retests of the same child differed much from one another; for we could hardly suppose that the effects of the inhibitions were so nicely proportioned quantitatively as always to produce the same proportional (not absolute) effect at any age (thus leaving the apparent I.Q. constant so far as they were concerned), especially in view of the fact that at later ages a child is tested by questions wholly or partly different from those employed at earlier ages. On the contrary we should expect the interference of the affective factors to be quantitatively unequal, and more or less arbitrary, and hence to find irregular variations in the I.Q.
1 Cf. for example, Dr Godfrey Thomson's Northumberland Mental Tests (Harrap), and the present writer's Simplex Group Intelligence Scale (Harrap).
What is found in practice? The very opposite is the case. There is a large and growing amount of data which shows that the I.Q. of a particular child, as measured by the tests, remains practically constant within the limits of experimental error. Retests have been conducted under varying conditions, by different examiners, and after varying intervals of time (some of several years' duration), and all go to reinforce the conclusion that the tests give a nearly constant I.Q. for each child1. There are no signs (except in markedly pathological cases) of the irregular variations which would inevitably arise from affective interference by inhibiting factors of the kind we are considering. Retesting therefore shows, not only that the I.Q. is at least a close approximation to the constant index aimed at, but also that affective inhibitions have at most but a negligible influence on the children's performances both in specific tests and in the scale as a whole.
We are thus bound to conclude that there is nothing in the nature of the tests themselves or in the results of their application which could warrant us in believing that affective inhibitions seriously interfere with the measurement of intelligence. At the same time we must end as we began by pointing out that finally conclusive evidence can only be obtained by retesting children after psychotherapeutic treatment. It is to be hoped that this important experiment may be carried out in the near future. Allied experiments of equal interest might consist in the application of mental tests during hypnosis, and also in cases of dissociated personality. In dissociations of the co-conscious type the comparison of the results of mental measurements made on the different personalities would be particularly interesting.
1 The only general exception to this statement occurs with mental defectives (especially the lower grades) where a noticeable drop in I.Q. seems to occur with increasing age.