Eysenck (1952a) has postulated the existence of three main dimensions of personality: Extraversion, Neuroticism and Psychoticism. These are conceived of as independent of each other, and as continuous, with neurotics and psychotics respectively marking the extreme ends of the N and P dimensions. Within each dimension, the particular type of neurotic or psychotic illness is considered to be determined by the degree of extraversion of the patient; thus dysthymic and hysterical disorders mark the introverted and extraverted types of neurotic illness (Eysenck, 1947), while within the psychotic field degree of social withdrawal might be considered to be the variable most closely related to introversion/ extraversion (Venables and Wing, 1962). Hypotheses have also been formulated to account for the causal factors underlying E and N (Eysenck, 1967), although no such hypotheses have been elaborated with respect to P. A special statistical technique (criterion analysis—Eysenck, 1950) has been worked out to test the crucial question of continuity between normal and abnormal (neurotic and psychotic) populations with respect to N and P; application of this method has given support to the theory of continuity (Eysenck, 1950, 1952b).

Twin studies and investigations into the relationship between schizophrenia-like psychosis and cerebral dysfunction are of considerable interest. Refinement in twin studies has led to less emphasis being placed upon the genetic factor, but the pitfalls surrounding twin techniques, especially with regard to monozygous pairs and the similarity of their environment, have led Penrose (1971) to the opinion that twin study ‘is especially useful, not for genetical researches but in assessing the effects of environmental influences which lead to discordance in identical twin pairs'.

This paper is an extension of an earlier introductory one (1) and evaluates the results of treatment with parenteral and oral chlorimipramine of 200 patients suffering from depressive states of varying severity. The current research project was started in January 1968, and is still in progress. Further references to the literature may be obtained from the original paper or by application to the author. Fifty-seven of the cases treated were so severely depressed that ECT would normally have been given. All were in-patients and were treated with intravenous infusions of chlorimipramine. The other 143 patients were less severely depressed and were seen as out-patients. They were treated with increasing doses of oral chlorimipramine, but a few cases in both groups also had ECT to expedite recovery. Approximately 50 patients exhibited obsessional features in addition to depression, and their response to treatment was so promising as to merit special mention.

In Autumn, 1971, the Director of the Office of Health Economics stated that ‘the majority of the population regard homosexuality as an abnormality justifying medical treatment‘.

Over the years investigators have described psychiatrically abnormal individuals in the families of schizophrenics. These unusual persons have been given a variety of names: schizoids, schizoid psychopaths, and the condition called schizoidia or schizophrenia-spectrum illness (Kahn, 1923; Planansky, 1966). With recent developments in family and adoptive studies of schizophrenia which have indicated a genetic factor playing a causative role, the schizoid state has assumed more importance, especially in estimating the type of inheritance (Heston, 1970). Furthermore, the schizoid state is of considerable interest from a clinical standpoint since it may represent a ‘forme fruste’ of schizophrenia, and as such a study of schizoids from the point of view of the factors which may have prevented a full-blown schizophrenic process would be of great interest.

The successful investigation and development of effective treatment programmes for any disorder is closely dependent on the development of reliable and valid assessment procedures. Anorexia nervosa would seem to be no exception in this respect. At present, while the diagnosis of anorexia nervosa seems fairly easy to establish, the assessment of severity, response to various treatment regimes, and prognosis pose rather more of a problem. Reliance on criteria such as weight status and gain, return of menstruation, psychosexual adjustment, etc., is inadequate, especially in the assessment of short-term effects of various therapeutic conditions. Recently Slade and Russell (1972) have described an objective technique for measuring ‘perception of body size‘, an area in which they found anorexia nervosa patients to be defective. Clearly, however, other reliable, objective assessment techniques are needed as well.

Many patients in hospitals for the mentally subnormal are very isolated from the community (Ballinger, 1970). McKeown and Leck (1967) suggested that many individuals in these hospitals do not require hospital care and there have been recommendations that hospitals for the subnormal should be smaller in the future (Department of Health and Social Security, 1971).

Much has been said and written about the logical status of diagnoses; their reliability and validity have often been measured and questioned; and several mathematical models of the diagnostic process have been developed for use in computers. But surprisingly little interest has been taken in the practical aspects of diagnosis as a decision-making process. A large and undistinguished literature on ‘psycho-diagnostics' was generated by clinical psychologists in the 1950s, but this was largely concerned with diagnoses derived from cognitive and projective test results and so has little relevance to diagnosis by the traditional medical method of asking the patient about his symptoms. More recently a few people, like Gauron and Dickinson in Iowa and Sandifer in North Carolina, have studied the diagnostic activity of psychiatrists in specially designed experimental situations, and their findings have been both interesting and instructive. But we are still uncertain at what stage in a diagnostic interview a provisional diagnosis is usually arrived at, or how often this initial impression is correct, or is changed later on. Nor do we know the relative importance of the patient's behaviour and the factual information he provides in reply to questions, or what differences exist between psychiatrists in the means by which they reach a diagnosis, or in the speed and confidence with which they do so. The studies described here were designed with the aim of shedding some light on these matters.

Unilateral ECT (U/ECT) produces therapeutic generalized convulsions with less amnesia and confusion than classical bilateral ECT (B/ECT). The clinical effects of these two methods have recendy been compared (Abrams et al., 1972) and reviewed (Abrams, 1972), with the conclusion that U/ECT is less effective than B/ECT in the treatment of depressed patients. Generalized seizures are induced with both methods, and we considered the possibility that the therapeutic advantage for B/ECT lay in its bilateral stimulation of the brain. An opportunity to evaluate the effects of bilateral stimulation exclusive of the temporal lobes arose at the suggestion of Inglis (1970) that seizures induced with treatment electrodes placed over the front of the head should improve mood but have less effect on memory than the other techniques.

Boulton (1971), in an authoritative review, has pointed out that biochemical research into schizophrenia has depended upon the assumption that hallucinogens, such as mescaline and LSD produce a state similar to schizophrenia, and that such research has therefore principally been concerned with attempts to find hallucinogens, or substances closely related to them, in the bodily fluids of schizophrenics. Since this model has been criticized on phenomenological grounds, we decided to make a comparison between states of visual hallucinosis and of schizophrenia with thought disorder, using a measure which tests a common hypothesis concerning the origin of schizophrenic symptoms. This hypothesis suggests that the symptoms of schizophrenia are manifestations of failure of a hypothetical sensory ‘filter’ (Broadbent, 1958). This mechanism determines the individual's ‘selective inattention’ to the irrelevancies of his environment. Its function can be assessed by a study of habituation, which is the process whereby a randomly repeated stimulus fails in time to elicit an orienting response.