The social behaviour which is the material of psychological observation at any given time is the product of a certain genetic constitution on the one hand, and of a complex process of social, educational, familial and, to some extent, uterine environment on the other. The social behaviour of human beings cannot be subjected to direct methods of genetic analysis. The genetic psychologist may be compared to the astronomer, in so far as he has to rely on Nature to perform the experiments which he himself is unable to undertake. To the category of such experiments belongs the phenomenon of twin production. In the production of monozygotic twins Nature provides us with individuals of the same genetic constitution. Such differences as they exhibit arise uniquely from the operation of differences in the environment in which they are placed. In ordinary circumstances they share many more features of environment than any other two individuals selected at random from the population. When reared together, the extent of their dissimilarity can only throw light on such differences of nurture as may operate on members of the same family unit and of the same age. If they are reared apart, the measure of resemblance exhibited by monozygotic twins may throw light on the influence of social environment in a less restricted sense. With a sufficiently large sample of twins reared apart, a satisfactory standard of comparison for assessing the extent of resemblance due to genetic constitution, plus the effects of a common uterine environment, would be provided by the degree of resemblance existing between their foster sibs in families into which they have been adopted. Such data cannot be collected easily. As yet they do not exist in sufficient quantity to yield satisfactory conclusions.

In this paper a series of twenty-six cases of schizophrenia are analysed. This study has been confined very largely to a consideration of their feelings of unreality, hallucinations and disorders of imagery, as it was found that the particular method used was most applicable to these features of the total symptomatology. Such a selection from the whole range of schizophrenic activity might appear arbitrary since there is, of course, an essential unity in all psychic happenings, as, amongst others, Mignard (1), Berze (2) and Kronfeld (3) have pointed out. Nevertheless, Mignard himself says that affect, will, knowledge and memory are involved in every single psychic act. C. Schneider (4) also has demonstrated that schizophrenic characteristics show the same easily recognizable form in all their deviations from the normal psyche.

I am fully aware of the honour and responsibility conferred on anyone who is asked to deliver a Maudsley Lecture. That great physician realized that the knowledge of medicine advances by devious paths. I have availed myself of his broadmindedness to lay before you to-day some of the physical symptoms associated with a group of mental cases labelled “acute confusional insanity I will lay before you facts which support the belief that in all these cases the departure from health affects the functions of the whole body, the heat-regulating centre, the cellular and serum defences, the renal functions, the carbohydrate metabolism, and the effect of the injection of insulin on low blood sugar.

A well-known novelist recently made the cogent statement that nothing that happens is important except as it happens to some person. Just as there is no sound without an ear to hear it, so there is no behaviour without some person to observe or experience it. We may elaborate this thought into the dogmatic statement that no behaviour is important except in terms of its social value. While this is not strictly true of those intimate experiences which take place within the self as a unique organism, nevertheless even such intimate personal behaviour is irrelevant to everyone else except in terms of its social impact.

The incidence of schizophrenia among admissions to mental hospitals has been variously estimated at from 12% to 16%. These statistics ignore the pre-psychotic states and all those schizoids who have, in these modern times, been assisted to exteriorize or readjust themselves without the invocation of the Lunacy Laws.

This contribution is an attempt to express in numerical terms the value of out-patient consultation and treatment. The group of cases considered are the first 150 who presented themselves at the Psychiatric Out-Patient Department of the Swansea General Hospital, and they are consecutive and unselected. The period during which these cases came under observation for the first time extends from March, 1933, to October, 1934; and, in assessing results, the state of the patients is taken as at December 31, 1934.

There are in the wards of every mental hospital numbers of persons who for long periods of time exhibit profound disorders of emotion. Thus, we note the fixed depression of the melancholic, the boisterous exuberance of the manic, and the mechanical indifference of the primary dement.

The studies here reported are concerned with the application of some of the techniques of measurement to problems of mental health. They constitute the preliminary steps in a programme of research that envisages: (i) the possibility of assisting mental diagnosis by means of objective experimentation, the purpose of which is to isolate variables in personality that are significant in their relationships to degrees of mental stability; (ii) the functional interpretation of these variables; (iii) the employment of any quantitative criteria that can be thus established, in demonstrating the influence of therapeutic and positive mental hygiene programmes.

The objects and advantages of ascertaining the actual and relative measurements of various parts of the body are numerous. For example, this method has been largely used by anthropologists for classifying different races of mankind.

In this paper an attempt has been made to ascertain the after-histories of a particular group of patients discharged from the Maudsley Hospital, namely, those for whom further institutional treatment was considered necessary, but in whose case this advice was not taken. The investigation covers a period of three years, from 1928 to 1931. At the outset it must be pointed out that the Maudsley Hospital deals exclusively with voluntary patients, who are free to leave on giving twenty-four hours' notice; in addition, no patient is certified in the hospital, but where this is considered necessary, the friends are advised as to the procedure to be followed. In the circumstances, it might be thought that the number of patients who were taken home against advice would be high; but this was not the case. In a number of cases further institutional treatment was deemed necessary on grounds of psychotherapy alone; and if these are excluded, only 90 patients remain who were considered unfit for any but institutional care, either because they were dangerous to themselves, or because they were likely to prove dangerous or at least a nuisance to others. During the period under review 3, 248 patients were admitted to hospital and 2, 282 were discharged, so that the cases dealt with in this paper constituted only 2–8% of admissions and 3.5% of discharges. Of the 90 patients, 50 were females and 40 males. The length of stay in hospital varied from one day to one year.

The employment of malaria as a therapeutic agent in the treatment of general paralysis has focused attention on the latter disease and has provided much material for thought. A discussion on the prognosis and treatment of general paralysis was sponsored by the Association at the quarterly meetings in November, 1928, and February, 1929. The Sections of Psychiatry and Neurology of the Royal Society of Medicine had a similar discussion at the same time, and quite recently the Neurological Section of the Royal Society of Medicine debated the unsettled problems of neuro-syphilis, when the President, in summing up, remarked, “Our problems still remain unsettled”.

In considering the structure of the central nervous system as the vehicle for the mind, due regard must be paid to the vast amount of psychological knowledge which has been accumulated, and any new theories advanced must at least to some extent be able to explain accepted psychological material in neurological terms.

Kraepelin and Morel were the first to emphasize the fact that tuberculosis is more common in schizophrenics than in other psychotics. Later on, Ganter, Zalla and Bonasera confirmed this statement with the support of a wide statistical inquiry. Thus Ganter found the mortality from tuberculosis in schizophrenics to be from 46 to 67%, whilst the general mortality-rate in tuberculosis in the Prussian asylums was only 16.6%; Bonasera found the tubercular mortality-rate to be 61.7%, and Zalla 67.5% in their autopsies on schizophrenics.

Miss Simmins and Dr. Stephenson in their recent articles in this Journal have given some account of the “g” and “p” factors of the Spearman school, studied in relation to psychiatry. The part of the present writer in the research was to find some means of assessing factors in the field of conation and volition. The research consisted of two parts, a first tentative experiment carried out at Horton Mental Hospital in 1930–31 and a final experiment in 1932 at the Maudsley Hospital, Bethlem Royal Hospital and at Horton, by the courtesy of Dr. E. Mapother, Dr. Porter Phillips and Dr. Nicol, to verify the results of the first experiment and to secure more finely-graded results. The cases were carefully selected by the psychiatrists concerned, and the writer is greatly indebted to them for their generous assistance, particularly in the matter of supplying detailed estimates of personality traits.

The relationship between mental disorders and diabetes is studied as shown by 30 cases of mental disorder associated with diabetes, 93 cases of uncomplicated diabetes and 400 uncomplicated cases of mental disorder. This study covers, first, the psychological picture in diabetes; second, the types and courses of mental disorder associated with diabetes; and third, the mental symptoms with hypoglycæmia.

In support of the theory of a toxic genesis of mental diseases arising from chronic infection, some authors have attributed a special rôle to the B. coli. As long ago as 1904 Johnsohn and Goodall (1) examined the agglutination of a series of psychotics to the B. coli. They found this reaction completely or weakly positive in 50% of their cases of insanity (mostly with a serum dilution of 1: 100), while only 15.5% of their control cases showed a positive reaction. These results were not confirmed by Puca (2). Later on Goodall, together with Barton White (3), also examined the stool flora of psychotics, and found no qualitative difference as to the coliform group between psychotics and normal persons. On the other hand, Stewart (4), in more recent experiments, claims to have found such differences; thus he emphasizes the much higher frequency of the B. para-coli and B. coli mutabile in mental patients, especially in recent cases, and the parallelism between their presence and the intensity of the symptoms. Further, he found a difference in the phenol formation in broth cultures obtained from stools-of psychotics and normal persons, the former producing on the average 0.02 to 0.03%, and the latter only 0.008 to 0.03% of phenol. This stronger production of phenol is attributed by Stewart to the high frequency of B. Morgan and other phenol-producing bacteria in psychotics. He discusses the possibility that aromatic bodies produced by these bacteria in the acid milieu of the large intestine may represent the toxic agent in mental diseases.

By “perseveration” is intended the lag or persistence (“inertia”) of a mental process. That is, perseveration refers to process-lag as a function of the individual. It is probably best studied in terms of the effect of its presence on another immediately subsequent process. It is indirectly manifested in the realm of mental content, and the effect is usually appreciated as “interference”, “inhibition” or “carry-over”, which are symptoms of its presence.

“Unfitness to plead” is a medico-legal proposition of practical importance to prison medical officers. My attention was drawn to it, shortly after I joined the Service, in a case tried at the Central Criminal Court. Since then I have frequently had to take the responsibility of forming an opinion and reporting as to prisoners' fitness or unfitness to plead, and recently my interest in this problem has been re-aroused by a case tried at the Manchester Assizes, the outcome of which I had discussed with my colleagues and also with members of the Bar.