D.J. Done

Experiences of alien control in schizophrenia reflect a disorder in the central monitoring of action

Twenty-three acute psychotic patients who were drug free at the time of testing performed a motor task designed to elicit many errors. Normal subjects and many of the psychotic patients were able to correct these errors in the absence of visual feedback. The ability to make such corrections depends on the subject knowing what response he has just made. Patients with experiences of alien control of their thoughts and actions who formed a subgroup of those classified as schizophrenic, were significantly less likely to make error corrections in the absence of visual feedback. This result is consistent with our previous suggestion (Frith, 1987) that these symptoms are a consequence of problems with the central monitoring of responses.

Childhood antecedents of schizophrenia and affective illness: social adjustment at ages 7 and 11.

Abstract Objective: To investigate the social adjustment in childhood of people who as adults have psychiatric disorders. Design - Subjects in a prospectively followed up cohort (the national child development study) who had been admitted as adults to psychiatric hospitals were compared with the rest of the cohort on ratings of social behaviour made by teachers at the ages of 7 and 11 years. Subjects: 40 adult patients with schizophrenic illnesses, 35 with affective psychoses, and 79 with neurotic illness who had been admitted for psychiatric reasons by the age of 28. 1914 randomly selected members of the cohort who had never been admitted for psychiatric treatment. Main outcome measures: Overall scores and scores for overreaction (externalising behaviour) and underreaction (internalising behaviour) with the Bristol social adjustment guide at ages 7 and 11. Results: At the age of 7 children who developed schizophrenia were rated by their teachers as manifesting more social maladjustment than controls (overall score 4.3 (SD 2.4) v 3.1 (2.0); P <0.01). This was more apparent in the boys (5 (2.6)) than the girls underreactive behaviour. At both ages prepsychotic (affective) children differed little from normal controls. By the age of 11 preneurotic children, particularly the girls, had an increased rating of maladjustment (including overreactions and underreactions). Conclusion: Abnormalities of social adjustment are detectable in childhood in some people who develop psychotic illness. Sex and the rate of development of different components of the capacity for social interaction are important determinants of the risk of psychosis and other psychiatric disorders in adulthood.

COMPLICATIONS OF PREGNANCY AND DELIVERY IN RELATION TO PSYCHOSIS IN ADULT LIFE - DATA FROM THE BRITISH PERINATAL-MORTALITY SURVEY SAMPLE

OBJECTIVE--To evaluate whether events occurring at or around the time of birth contribute to the onset of psychotic illness in adult life. DESIGN-Pregnancy and birth complications as possible causes of adult mental illness were studied in the population sample of the British perinatal mortality survey. Subsequent psychiatric admissions were independently identified through the Mental Health Enquiry and records of regional and special health authorities. Logistic regression was used to compare data on perinatal deaths with those on survivors to determine factors independently associated with perinatal death, and this equation was then used to calculate the risk of perinatal death for each survivor. SUBJECTS--16,980 people born in a single week in 1958 (the British perinatal mortality survey sample), including 252 patients admitted to psychiatric care; case notes of 235 patients were supplied. MAIN OUTCOME MEASURES AND RESULTS--Patients with a schizophrenic illness (whether defined by broad (n = 57) or narrow (n = 35) diagnostic criteria) did not have a greater mean risk of perinatal death than the population in general, but there was some evidence of increased liability (relative risk 2.43; 95% confidence interval 1.17 to 5.05) for those with affective psychosis (n = 32). Specific high risk variables for affective psychosis were decreased gestation time (273.9 v 281.2 days; mean difference 7.3 days, 95% confidence interval 3.1 to 11.5; p less than 0.002) and prescription of vitamin K to the child in the first week of life (19% of patients v 5% of controls, p = 0.016). CONCLUSIONS--The findings give no support to theories that factors predicting perinatal mortality contribute significantly to causation of schizophrenic illness. Further investigation of decreased gestation length in relation to affective disorder is required.

Routes to action in reaction time tasks

SummaryTwo-choice tactile RTs are no faster than 8-choice tasks, implying the existence of a ‘direct’ route. However, simple tactile RTs are much faster than choice tactile RTs (Leonard, 1959). In Experiment I we show that this is not due to subjects anticipating the stimulus in simple tactile RT tasks. Increasing probability of stimulus occurrence at a particular time led to equally decreased tactile RTs for simple and choice tasks.We suggest that an alternative route is available for simple RTs which is faster than the ‘direct’ route available for choice tactile RTs. This route is faster because (a) the response can be specified in advance, and (b) the stimulus does not need to be identified. The subject needs merely to register that it has occurred. In Experiment II we show that simple RTs to a visual stimulus are decreased by a simultaneous uninformative tactile stimulus even when this is to the wrong finger. This confirms that exact stimulus identification is not necessary in the ‘fast’ route. In Experiment III we show that a secondary task slows down simple tactile RTs to the same level as choice tactile RTs while the latter are hardly affected. This suggests that focussed attention is not needed for the ‘direct’ route, but it is needed for the ‘fast’ route. We propose that a useful distinction can be made between action largely controlled by external stimuli (the ‘direct’ route) and action largely controlled by internal intentions of will (the fast route).

A "mock up" of schizophrenia: temporal lobe epilepsy and schizophrenia-like psychosis.

Schizophrenia-like psychoses occur more frequently than expected in patients with chronic temporal lobe epilepsy. We have analyzed pathological and clinical data from a series (n = 249) of temporal lobectomies to determine the factors that may relate to the development of schizophrenia-like psychosis. Schizophrenia-like psychoses did not occur at random; they were significantly associated with lesions that (1) originated in the fetus or perinatally, (2) affected neurons in the medial temporal lobe, and (3) gave an early age of first fit. Gangliogliomas--developmental lesions of the medial temporal lobe containing aberrant neurons--were disproportionately (p less than 0.001) associated with risk of psychosis. Schizophrenia-like psychoses arising preoperatively occurred more often (p = 0.1) with left-sided lesions. Asymmetry of lesion was not present in cases with postoperative psychoses. These findings are of interest in relation to recent studies suggesting that the structural abnormalities found in the brains of schizophrenics arise during fetal brain development.

Obstetric complications in children born to parents with schizophrenia : a meta-analysis of case-control studies

On the basis of previous findings, we used meta-analyses to consider whether births to parents with schizophrenia have an increased risk of obstetric complications. Meta-analyses were based on published studies satisfying the following selection criteria. The schizophrenic diagnosis could apply to either parent: parents with non-schizophrenic psychoses were not included: only normal controls were accepted. In all, 14 studies provided effect sizes or data from which these could be derived. Studies were identified by data searches through MEDLINE, PSYCLIT and through references of papers relating to the subject. Births to individuals with schizophrenia incur an increased risk of pregnancy and birth complications, low birthweight and poor neonatal condition. However, in each case the effect size is small (mean r = 0.155; 95% CI = 0.057). The risk is greater for mothers with schizophrenia and is not confined to mothers with onset pre-delivery or to the births of the children who become schizophrenic themselves.

The Northwick Park ‘Functional’ Psychosis Study: diagnosis and outcome

Three hundred and twenty-six consecutively admitted patients with functional psychotic illnesses to which no diagnostic classification had been applied were followed up after 2.5 years. They were examined in social, clinical and psychological terms and the CATEGO programme and DSM-III criteria were applied to data concerning the index episode to derive diagnostic classifications. The deterioration in occupational functioning and the hospital careers of patients with diagnostic classifications of schizophrenia were worse than those in the other groups and positive and negative features were also more severe in patients with a classification of schizophrenia. By contrast, no differences in psychological test performance were found between the groups based upon diagnostic classification. Impaired psychological test performance was found and it was strongly related to concurrent mental state abnormalities, particularly negative symptoms. It is concluded that the diagnostic classifications used were of limited value in predicting outcome in functional psychosis.

Combination tricyclic antidepressant and lithium maintenance medication in unipolar and bipolar depressed patients.

In a small study of up to 3 years duration comparison of the value of amitriptyline alone versus amitriptyline + lithium in unipolar cases (27 patients) and of that of lithium alone versus amitriptyline + lithium in bipolar cases (13 patients) showed no advantage for the combination treatments in terms of efficacy in reducing depressive relapses. There was no effect of treatment, developing depression or developing hypothyroidism upon the psychological tests which were conducted during this prolonged study. Observer and self ratings detected an increase in depression before relapse was clearly present, but of the various psychological assessments conducted only arousal showed changes in association with developing and definite relapse. The prescription of lithium but not amitriptyline + lithium or amitriptyline alone was associated with significant increases in blood pressure.

Automatic and strategic volitional saccadic eye movements in psychotic patients

SummaryDrug-free schizophrenics were compared with depressive psychotics and normal controls on two saccade initiation tasks which differed with respect to the type of stimulus that initiated a saccadic response. Strategic initiation (SIS) appears to use a route different from that in automatic initiation (AIS). The SIS task revealed slowed responding in psychiatrically ill patients if their cognition was impaired, but all groups responded similarly on the AIS task. Schizophrenics could be separated from depressed psychotics by their inability to utilize temporal redundancy to speed up saccade initiation on the SIS task. Neurophysiological evidence implicates specific impairments in the frontal eye field (FEF) and/or basal ganglia.

A longitudinal study of the development of visual field advantage for letter matching

The visual field advantage for letter matching was investigated longitudinally from 5 to 7 yr. A right visual advantage was found with very little indication of any increase with age. Cross-sectional controls exhibited somewhat less of a right visual field advantage. In a group of 4-yr-olds who could not name letters a left visual field advantage was observed for boys. It is suggested that the right visual field advantage for visual-verbal material occurs from a mapping on to an already existing left hemisphere language system.