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.

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 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.

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.

During the last ten or twelve years a great deal of study has been devoted to cholesterol, its metabolism and variation in disease, and its rôle in mental disorder. Since 1926, investigations on this line, laboratory and clinical, have been carried out at Severalls Mental Hospital, and the object of the present paper is to summarize this research, especially in the light of other work, and to indicate what conclusions might be formed.

During the last decade prolonged narcosis has been accepted as a most valuable form of treatment in mental disorder, but many psychiatrists refuse to use it because of its dangers. The present paper presents clinical and laboratory evidence that a method has been devised whereby most of the toxic symptoms can be obviated. It is claimed that a large proportion of these symptoms are due to upset of carbohydrate metabolism of the liver and heart by the narcotic, and that in the administration of insulin and glucose as an integral part of the treatment a rational method of prevention has been evolved. No attempt is made to record the results of treatment, as it is proposed to publish this separately, the aim of the present paper being to show the elimination of toxic symptoms by the suggested modification of treatment.

In the whole realm of medicine there are few more easily recognizable clinical syndromes than those which have been grouped together under the generic term of “epilepsy” or “epileptiform convulsions”; nevertheless, in spite of a vast amount of research work, the causation of these conditions is still imperfectly understood.

In recent years new avenues of approach to the treatment of epilepsy have been opened up, investigation and experiment have been stimulated, and, especially in young patients, definite hopes of cure have been held out. Experiments in metabolism have shown that a condition of acidosis is antagonistic to epileptic seizures. The ketogenic diet is one designed to produce acidosis artificially, this being achieved by reducing the carbohydrates and greatly increasing the fats.

Hippocrates was the first to regard epilepsy, not as a “sacred disease” but as a disorder due to natural causes. He believed that a causal relationship existed between humidity of the brain and the epileptic crisis—a hypothesis that in recent years has assumed prominence following the work of Temple Fay (27) and McQuarrie (28). According to Fay an abnormal increase in intracranial pressure is brought about by the accumulation of fluid over the cortex, due to impairment of function of the Pacchionian bodies.

In the earlier papers of this series Stephenson has already reported an experiment in psychiatry, in which patients at Horton Mental Hospital have been tested by psychologists of the Spearman School of Factors.∗ The p-factor has been introduced and its contact with psychiatric material developed. The present paper serves to introduce the general factor in cognition (“g”), and to indicate the significance of measures of the g-factor for psychiatric research.

This study was undertaken in the furtherance of a project outlined in an earlier paper (I), namely, the development of objective means of estimating the progress of psycho-biological reactions. Perseveration has been touched upon in an earlier investigation, and it was determined to examine more closely what seemed to offer the possibility of a valuable mode of measurement.

The use of occupational therapy in mental or physical illness, as an adjunct to medical treatment, has developed rapidly during the past twelve years. As definitions often prove a snare to the uninitiated, and as no comprehensive phrase has been coined for this scientifically applied activity, it seems advisable to give a short survey—based largely on experience gained in the United States—of the manner and degree in which this therapy is contributing to the recovery of the sick to-day.

In the Journal for April, 1932, there was published the “Final Revision of the Classification of Mental Disorders drawn up after two and a half years' consideration and discussion by the Clinical Psychiatry Sub-Committee.

During the past year interest in occupation therapy has been greatly stimulated by the visits, organized by the Study-Tours Sub-Committee, to Gütersloh, where the system associated with the name of Dr. Simon and often spoken of as “active therapy” originated, and to Santpoort, where this system has been most thoroughly applied outside Germany. Following these comes the Board of Control's Memorandum,∗ reviewing the present position, and making definite recommendations for the initiation and development of occupation therapy on similar lines.