“Dysphoria, or misery, in various degrees, is perhaps the most frequent and most widespread of all disorders of mind, and that with the most numerous associations with other disorders.”—Mercier's Text-book of Insanity.

It is many years now since Jung first drew attention to what he believed to be of far-reaching significance in the psychological understanding of human personality: the presence of two great psychological divisions of mankind, the outwardly directed or “extraverts”, whose interests and activities turn mainly towards the outer world and whose lives correspond directly with objective conditions, and the inwardly directed or “introverts”, who are influenced more by subjective factors, and whose attitude to the outer world is an abstracting and depreciatory one.

I have the honour to present to this Association the compliments and good wishes on the American Association on Mental Deficiency, formerly the American Association for the Study of the Feeble-Minded. Permit me also to express the admiration of students in the field of mental deficiency in the United States for the long record of excellent work on this problem in England. We have appropriated much of your information; and your conclusions have strongly influenced our professional points of view. I wish also to express my personal appreciation for the privilege and honour of addressing this Association, and to acknowledge the courtesy of your President, Dr. Turner, for his kind invitation to attend this meeting. My presence here is the fulfilment of a long-standing desire to be more immediately familiar with your work on mental deficiency and allied problems. It is a distinct personal and professional satisfaction to meet your leaders in this field, and to observe your achievements at first hand.

When I accepted the great honour of giving the Maudsley Lecture this year, I was instructed that my subject should be one of popular interest. The theme of “Education in Medicine” was chosen with some trepidation, not so much on account of any lack it might have of intrinsic interest, but because its elaboration might lead me to express views not entirely in harmony with popular opinion. “Education in medicine” rather than “medical education”, because I had it in mind to discuss the kind of instruction which, if within his reach, would enable the layman to recognize and appreciate some of the principles on which the practice of medicine is based and pursued. And my choice was determined by the conviction, which must be generally shared, that the practice of medicine is much handicapped by a want of understanding, and therefore of sympathy and co-operation, on the part of the public—a want of understanding, the causes of which might be explored with advantage to both parties concerned in it.

It was with a deep sense of responsibility and of gratitude alike that I accepted the invitation to address you as your fourteenth Maudsley Lecturer; a sense of responsibility through the thought that, in a way, I come as a representative of American psychiatry; a sense of sincere gratitude for an opportunity to acknowledge a real personal indebtedness to British science and British medicine and British psychiatry, partly for what I received myself in the long years since my early post-graduate work in this country forty-three years ago, and partly for the influence British thought and work and practice has had upon certain developments, for which it is a pleasure to express our indebtedness and appreciation. Some of these relations and connections are little realized and little appreciated, and yet very illuminating and by no means only personal.

The thyroid gland has a profound influence on the mind, both in its emotional and its intellectual aspects. The emotional features of hyperthyroidism are too well recognized to need stressing. So, too, is the association between gross diminution of thyroid function and the mental incapacity of cretinism. It was suspected, therefore, that even in those types of mental deficiency in which diminution of thyroid function was not recognizable clinically, it might be possible to detect some evidence of abnormality in the thyroid gland by histological study. Further justification for presupposing the possibility of thyroid derangement may be found in the fact that in many conditions an association between the thyroid and thymus has been established, and that in mental deficiency the thymus undergoes premature atrophy.

In the world of science it is generally found that virile opinions are those which are fortified with a rather effeminate equipment of evidence. One of the subjects of which this is true is mental inheritance. In early days it was simple and attractive to place the blame for the occurrence of mental disorders on heredity. It is now becoming apparent that preventive policies based on genetic principles divorced from exact scientific knowledge of human inheritance are no more likely to succeed, than curative efforts unfortified by a scientific understanding of the environment. Mental inheritance is not a problem of genetics alone; it demands all that the geneticist can contribute to the recognition of how the characteristics of an organism are influenced by those of its ancestors; it calls for all that the nerve physiologist can impart about the way in which the characteristics of an organism are influenced by the changing pattern of stimuli to which it is subject.

In a recent lecture on “Individual Psychology and the Bases of Science,” Dr. Crookshank declares that Adler “like Socrates … condemns … the pursuit of knowledge for its own sake, as a futile attempt to transcend the limits of human intelligence” (p. 54). Again (p. 48): “… the real problem is that of right living—the pursuit of knowledge for its own sake is a delusion and a snare, a delusion inasmuch as absolute knowledge is unattainable, and a snare inasmuch as it draws us away from the study of conduct”.

The following is an account of the cases of schizophrenia admitted to Broadmoor from 1900 till 1931.

The use of the term “schizophrenia” in place of “dementia præcox” has rendered the classification of these cases more accurate than would have been possible with the older name, and also made possible the inclusion of several cases which otherwise would have had to be left out.

When a defence of insanity is put forward in answer to a criminal charge amnesia for the crime is not infrequently affirmed, in fact East (2) states that it is more often alleged than any other mental anomaly. The defence of amnesia is at times raised when there are no grounds for supposing that the prisoner is suffering from loss of memory, but there are undoubted cases where the crime, generally homicidal in character, has been committed during a disorder of consciousness or the memory of it subsequently has been lost. It is therefore of the greatest importance from a medico-legal point of view to distinguish between real and simulated amnesia. While amnesia may be simulated in cases where there is no mental disorder present, there are also instances where loss of memory is feigned by individuals in whom there are other reasons for regarding them as mentally abnormal. In this connection it must be realized that memory also is sometimes malingered; a prisoner who by reason of insanity accompanied by amnesia has escaped the responsibility for his crime may presently arrive at the conclusion that a persistence of his loss of memory will tend to keep him confined in an asylum, and therefore he asserts a remembrance of his crime, the story of which he is likely to have become familiar with at his trial or elsewhere. Not all such false memories, however, are definitely malingered. A patient may have heard the story of his crime so often that in the end he becomes convinced that he actually remembers it.

In contrast with the vast literature devoted to the adult type, reports on the form of general paralysis which occurs in childhood or adolescence have been few and far between, and in this country the papers of Mott (I) and Watson (2) form the chief source of our knowledge of its clinical and pathological features.

In recent years there has been an increasing tendency for the papers presented at the meetings of this Association to deal with the application of science to industrial and social problems. The norms of science have been applied to the art of living. The rapprochement on this platform between the scientist and the man of practical affairs has gone even further. Valuable contributions have been made by administrators and leaders of industry which have indicated the scientific implications of the practical problems in their respective spheres; and by no means the least function served by these contributions has been that of propounding problems to the scientists.

Although the blood-urea level is not uniformly distinctive of any type of psychosis or phase of a psychosis, yet its estimation in general psychiatric practice is probably as useful as any other test or reaction in use to-day.

The drawings of children have been studied by many observers during the past forty years, and have yielded valuable information for the psychologist, the ethnologist and the pedagogue. Many of the studies were concerned with the development over a period of years of the drawings of a single child (Luquet (12), Stern (19), Eng (3)). Others were concerned with drawings taken from a large number of children of varying ages. Principal among these studies is that of Rouma (17) in 1912, drawn from a wide field, carefully and accurately observed, and published with a wealth of illustration. More recent researchers have employed the quantitative method, and McCarty's (14) study, published in 1924, is of value principally for its elaborate statistical survey.

It is necessary at the outset to define the limits of this paper. For those profound disorders of mind to which imbecility and idiocy belong, sufficient causes have been found in neural degeneration or acquired disease. Although the fundamental cyto-architectonics of these cerebral degenerates has not been clearly worked out, we can separate off, as a result of post-mortem findings, a group of cases, both congenitally and acquired, which belong to neurology rather than to psychology. Admitting the fact that both imbeciles and idiots have exhibited disturbances of behaviour and emotional control, there is no reason to deny that such phenomena are secondary to neural defects and to such glandular disorders as accompany these neural defects, or occur concurrently as indication of general congenital inferiority. Furthermore, a class of defectives of high grade can be marked off in whom the primary defect is glandular, and in whom the psychological shortcomings are also to be regarded as secondary. But when we turn to that considerable group of children with intelligence quotients of about 80%, the problem of cause assumes a different complexion. Cases that fall within the statutory limits can be enumerated because they require special supervision and control, or, at least, special educational treatment; but of those children who cannot be dealt with legally, or who merely pass muster within the school as dullards, very little can be said as regards their number and distribution, and unless they die of intercurrent illnesses and are brought to post-mortem, nothing can be stated as to the presence of cerebral degeneration, however minor in degree.

In 1923, under the title, “The Illusion of Doubles in a Case of Systematized Delusional Insanity” (1), J. Capgras and J. Reboul-Lachaux described for the first time an interesting syndrome of non-recognition. The case was that of a persecuted and megalomanic woman in whom there existed a condition of agnostic identification without disturbance of sensory or memory images. The patient postulated a series of “doubles” replacing the various persons of her environment, even her husband and daughter being included. During the course of a few months she complained that she had been shown one thousand doubles of her daughter. The person confronted was appreciated to resemble exactly the known individual, but on account of some subjective disorder, the ability to identify her was lost and the belief in “doubles” brought forward in order to explain this state of non-recognition.