The study to be reported was carried out within the framework of Personal Construct theory as proposed by Kelly (1955) and summarized in Bannister (1962).

In recent years an increasing number of workers investigating schizophrenic behaviour have concluded that many of the symptoms found in schizophrenia are related to a disturbance in the selective and inhibitory functions of attention. One of the earliest statements of this argument is found in Norman Cameron's (1938, 1939, 1944) concept of “over-inclusion”, which he used to describe the schizophrenic patient's tendency to include many elements irrelevant to the central idea in his thinking. Shakow (1962) reached the following conclusions in summarizing his own psychological studies of schizophrenia—“It is as if, in the scanning process which takes place before the response to stimulus is made, the schizophrenic is unable to select out the material relevant for optimal response. He apparently cannot free himself from the irrelevant among the numerous possibilities available for choice.” Weckowicz and Blewett (1959), in their studies of alterations in perceptual constancy in schizophrenic patients, interpreted their findings as suggesting that the patient's basic difficulty was that of “an inability to attend selectively or to select relevant information“. Venables and his colleagues (1959, 1962, 1963), in a series of studies on the arousal level of schizophrenic patients, also concluded that many of the behavioural abnormalities demonstrated were due to variations in the range of attention. In a series of investigations carried out by Payne and his colleagues (1960, 1961, 1963) to develop Cameron's concept of over-inclusive thinking in schizophrenia, the authors utilized Broad-bent's (1958) model of selective attention to postulate that this form of thought disorder is basically due “to a defect in some hypothetical central filter mechanism, the function of which

is to screen out irrelevant data both internal … and external … to allow for the most efficient processing of incoming information”.

In the preceding paper the effect of experimental distraction was examined and the findings discussed. The present report is concerned with a similar study of the effect of distraction on tests which involve another aspect of schizophrenic performance, that of psychomotor ability. Earlier studies (Chapman and McGhie, 1961, 1962) produced both clinical and experimental evidence that auditory distraction disrupted the motor responses of some schizophrenic patients. As the previous experimental findings were based on two tests involving only very limited areas of psychomotor performance, it was necessary to examine patients on a wide range of psychomotor tests. A second aim of the present investigation was to assess any differential effects due to variation in the sensory modality of the distracting stimuli.

Much of the current research on personality questionnaires has concerned itself with response style or bias related to “social desirability”, in which the first factor dimension of the M.M.P.I. is implicated (Edwards and Heathers, 1962). Stable personality differences have been detected between those who are placed high and low on this dimension as measured by a number of M.M.P.I. scales (e.g. Pt (Psychasthenia), K (Defensiveness), Taylor's MAS (Manifest Anxiety), Welsh's A (Anxiety) Scale—see Christie and Lindauer, 1963). However, a lack of integration has resulted from a failure to recognize that the same personality variable is being measured by scales of “social desirability”, “repression-sensitization”, or the tendency to deny or admit symptoms, and as well as “social desirability”, this factor has been identified as “general maladjustment or ego weakness” (Kassebaum, Couch and Slater, 1959), and “neuroticism” (Eysenck, 1962).

Under the concept of constitution are subsumed the predispositions towards illness, and the resistances against illness, to which genetical make-up and environmental experience have contributed during the preceding lifetime of the individual. It is in that sense that “constitution” will be used in the rest of this paper. Old age provides a vantage-point of particular value for the study of constitution, since it is possible to examine in retrospect over a long span of time the changes and vicissitudes which have affected it.

It has been accepted that the major factor in the aetiology of senile dementia is the organic brain disease which can be demonstrated histologically (Corsellis, 1962). The work of Rothschild (1936) suggested that psychological differences between individuals might be contributory, and Sands and Rothschild (1952) claimed evidence that senile psychotics have similar pre-morbid personality traits to those found in involutional melancholies and that hypochondriasis, dependency and rigidity were prominent features in both. A similar opinion is given by Noyes and Kolb (1958), who believe that, “the person who develops senile dementia has often been characterized by rigid and static habits”.

The future of the psychiatric services, in particular of the mental hospital, has been the source of much speculation since the publication of the Hospital Plan for England and Wales (1962). According to the Plan there would, by 1975, be psychiatric accommodation in each Region at the level of 1·;8 beds per 1,000 population, as estimated by Tooth and Brooke (1961).

It still seems to be current opinion regarding psychiatric in-patients that a bed requirement of 1·8 per 1,000 will cover all needs in the future.

The thalidomide tragedy in Europe has necessitated a re-examination of the use of tranquillizers and other drugs for the treatment of psychiatric conditions during pregnancy.

The urgent need to act and explain one's reasons is less pressing now in connection with witchcraft than in the days when it seemed to present an immediate menace to society. It has however always evoked intense reactions without a corresponding intense examination of the available evidence. The subject seems to invite partisan treatment.