Showing papers by "Robin M. Murray published in 1987"

Is schizophrenia a neurodevelopmental disorder

Abstract: A well established fact about schizophrenia is that first degree relatives have an increased risk of the disorder. Few now doubt that schizophrenia has a genetic basis, yet its mode of inheritance has to be explained. Even the identical twin of a schizophrenic stands a better than 50% chance of escaping the illness.' Genetic factors are not the whole story. Kraepelin, who derived the concept of schizophrenia, considered that both heredity and organic brain disease were implicated, but somehow the organic aspects were neglected until the publication of a study using computed tomography by Johnstone et al in 1976.2 A decade of such research has confirmed that the cerebral ventricles or cortical sulci are enlarged in many schizophrenics. Such changes are nonspecific and can follow head injury, intracranial infections, and alcoholism and other cerebral insults.3 As they are present in the earliest stage of schizophrenia and are not progressive they may be the sequelae of earlier events of aetiological importance. But what events-and how early? The epidemiology ofschizophrenia probably still holds the key. The disorder generally begins in early adult life, but the peak incidence in men is nearly a decade earlier than that in women.4 The reason for this is unclear. An equally puzzling but equally consistent finding is the small excess of births of schizophrenics in the cold winter months.5 This excess is not shared by the siblings of schizophrenics and is greater in those without a family history and in men with paranoid illness.67 The most likely explanation is that some environmental factor associated with winter birth causes neural damage in the fetus or neonate. The cause could be a viral infection or a seasonal difference in other complications that occur during pregnancy or delivery.8 9 Schizophrenics seem more likely than controls to have a history of obstetric complications,'0 11 and, despite the various events encompassed by the term, obstetric complications may increase the risk ofschizophrenia. Furthermore, increased ventricular size and other abnormalities seen on computed tomography are more common in those schizophrenics with a history of obstetric complications.\"2 Much research implicates the left rather than the right cerebral hemisphere in schizophrenia.'3 There is evidence that schizophrenics are more likely to be left handed than controls,'4 and possibly the normal development of lateralised cerebral dominance can be disrupted by premature birth with a resultant increase in left handedness.'5 What mechanism could explain the relation between obstetric complications, abnormalities on computed tomo-

The familial/sporadic distinction as a strategy in schizophrenia research.

Abstract: The rationale and limitations of discriminating between cases of schizophrenia with and without a family history are reviewed. It is concluded from the evidence available that, by identifying subgroups of greater aetiological homogeneity, the strategy can be a useful starting point for research into likely causes.

Familial aspects of obsessive-compulsive neurosis.

Abstract: The first-degree relatives of 50 obsessive-compulsive patients and those of matched controls completed the General Health Questionnaire (GHQ) and the Leyton Obsessional Inventory (LOI). Relatives who were identified as possible 'cases' by their high GHQ scores, or by their own or informant relatives' reports, were interviewed using the Schedule for Affective Disorders and Schizophrenia. Index relatives had a significantly higher lifetime prevalence of mental illness (36%) than had those of controls (17%), due mainly to an excess of depressive and neurotic disorders. However, only one relative from each group was diagnosed as having definite obsessive-compulsive neurosis. In addition, the LOI scores were similar for the index and control relatives.

Genetic and environmental variation in menstrual cycle: histories of two British twin samples.

Abstract: Information about menstrual cycle variables was obtained by questionnaire using 462 female twin pairs. The twins were either members of the Institute of Psychiatry Volunteer Twin Register, or of the Birmingham Population-based Register. The two samples were analysed separately using univariate and multivariate methods so that an independent replication was obtained. Maximum likelihood estimation was used to fit simple models of genetic and environmental variation to these data. The results suggest that age of menarche, menstrual cycle regularity and premenstrual symptom reporting may be heritable, whereas menstrual cycle length is not. The result should be interpreted with caution as not all variables were replicated in the smaller sample, and the method of retrospective menstrual cycle data collection has been questioned.

Family history and birthweight in monozygotic twins concordant and discordant for psychosis.

Abstract: In a sample of monozygotic twins, intrapair differences in reported birthweight were larger in those pairs discordant for later psychosis, compared to pairs concordant for psychosis. A trend towards less family history of psychiatric disorder was also found in the discordant pairs.

Schizophrenia: Is the concept disintegrating?

Abstract: The enigma of schizophrenia remains unresolved, but there have been significant advances in recent years. These have come from more reliable methods of diagnosis, more sophisticated brain imaging techniques, and improved genetic and epidemiological studies, For the reader of this journal, perhaps the most important development has been the repositioning of research efforts from a predominantly social orientation in the 1960s

Obstetric complications and cerebral abnormalities in schizophrenia

Abstract: The idea that adverse circumstances at or around the time of birth might play a part in the aetiology of neuropsychiatric disorders owes much to a series of studies by Pasamanick and his colleagues in the 1950’s. They assessed birth certification retrospectively in several large samples of children and compared their documented obstetric histories with those of normal controls. These studies established that rates of recorded obstetric complications (OCs) were increased in children with cerebral palsy, epilepsy, mental retardation, behaviour disorders, reading disabilities and tics (19). This prompted a reformulation of ideas concerning the pathogenesis of several of these conditions. For example, the aetiology of mental retardation, once considered almost entirely hereditary or familial, was increasingly regarded as multifactorial with environmental factors as important as genetic. Pasamanick (19) postulated “a continuum of reproductive casualty, consisting of brain damage incurred during the prenatal and perinatal periods as a result of abnormalities during these periods, leading to a gradient of injury extending from foetal and neonatal death, through cerebral palsy, epilepsy, behaviour disorder and mental retardation”.