Reduction in temporal lobe size in siblings with schizophrenia: a magnetic resonance imaging study.

Twenty-eight individuals with familial schizophrenia, from 16 unrelated families (12 sibling pairs and 4 individuals whose siblings refused scanning), and 21 normal control subjects were examined by cerebral magnetic resonance imaging (MRI). Measurements of the cerebrum, temporal lobes, and cerebral lateral ventricles were obtained using consecutive coronal sections containing these structures. Temporal lobe volume was significantly decreased by approximately 10% in these early onset schizophrenic siblings compared with normal controls. These findings add to recent post-mortem and neuroradiological evidence for morphological alteration in the temporal lobes in schizophrenia.

Schizophrenia as an anomaly of development of cerebral asymmetry. A postmortem study and a proposal concerning the genetic basis of the disease.

Schizophrenia is associated with structural changes (eg, a mild degree of ventricular enlargement) in the brain, although whether these precede onset of illness or progress with episodes is not established. In a postmortem study, we find that ventricular enlargement affects the posterior and particularly the temporal horn of the lateral cerebral ventricle. By comparison with controls and with patients suffering from Alzheimer-type dementia (in which there is also temporal horn enlargement), the change is highly significantly selective to the left hemisphere. This deviation was not accompanied by an increase in glial cell number (examined chemically by assay of diazepam-binding inhibitor immunoreactivity and microscopically by density of staining with the Holzer technique). The findings are consistent with the view that schizophrenia is a disorder of the genetic mechanisms that control the development of cerebral asymmetry.

Temporal lobe structure as determined by nuclear magnetic resonance in schizophrenia and bipolar affective disorder.

Temporal lobe structure has been assessed by magnetic resonance imaging in groups of patients with schizophrenia (n = 21) bipolar affective disorder (n = 20) and normal controls (n = 21). In the temporal lobe area a significant (p less than 0.05) diagnosis by side interaction was present, the area being less on the left than on the right side in patients with schizophrenia in contrast to findings in the two other groups. Lateral ventricular and temporal horn area did not distinguish the groups as a whole. However, there was a significant (p less than 0.05) relationship between lateral ventricular area and poor outcome, and in an analysis confined to males, patients with schizophrenia (n = 15) were found to have significantly (p less than 0.05) enlarged temporal horns.

The spectrum of structural brain changes in schizophrenia: age of onset as a predictor of cognitive and clinical impairments and their cerebral correlates.

A range of cerebral structures was assessed in a series of 172 CT scans of groups of psychiatric patients (including 101 in-patients with chronic schizophrenia) and related to assessments of clinical state and psychological function. Ventricular indices were increased in patients with schizophrenia by comparison with patients with other psychiatric disorders: brain area, which is modestly positively correlated with ventricular indices, was significantly (P less than 0.01) reduced in patients with schizophrenia. Among in-patients with chronic schizophrenia, measures of increased ventricular size were significantly associated with impaired social behaviour and with movement disorder. Memory for famous names in the distant past (a test of remote memory) was the only psychological test which showed significant associations with indices of ventricular size; this suggests that ventricular enlargement and its psychological sequelae occur relatively early in the disease process. Dichotomization of the sample of schizophrenic patients around the mean age of onset revealed that a range of clinical and psychological functions are significantly more abnormal in those with an early age of onset than in those in whom the onset was later. Early onset cases also perform less well academically and occupationally before illness onset. Within the early onset group some significant correlations between cognitive function and brain area were seen. The findings suggest that: (i) some at least of the structural changes in schizophrenia arise at a time when the brain is still developing; and (ii) age of onset is an important determinant of social and intellectual impairment and is relevant to the relationship between brain structure and cognitive deficits.

Is there gliosis in schizophrenia? Investigation of the temporal lobe.

Recent studies have described two indicators of pathology in the schizophrenic brain--gliosis and atrophy. The degree of gliosis in the temporal lobe of groups of schizophrenics (with demonstrable atrophy), affectives, and controls was quantified using immunocytochemical techniques and computer-assisted densitometry. Twenty areas within the temporal lobe were assessed. Our data showed no evidence of increased gliosis in the schizophrenic group compared to controls and affectives. This extends and replicates our previous findings, demonstrating that the atrophy/aplasia in schizophrenia is not associated with pathologically significant gliosis. Our observations are consistent with other studies, suggesting that the structural change in schizophrenic brains is due to an embryonic insult or developmental anomaly of an, as yet, undetermined nature.

Gliosis in schizophrenia: a survey.

Increased gliosis has been previously described in schizophrenic brain. In this study, the degree of gliosis in schizophrenic and control brains was assessed quantitatively using an antibody to glial fibrillary acidic protein, immunocytochemical techniques, and a computed image analysis system. Twenty separate brain areas were assessed, and no significant differences were found between the schizophrenic and control groups. It seems unlikely that a specific pattern of pathologically significant gliosis is present in schizophrenic brains. These negative findings are of note because of previously reported structural differences in the temporal lobe in the schizophrenic group in this series.

Hypothyroidism as a correlate of lateral ventricular enlargement in manic-depressive and neurotic illness.

Lateral ventricular size, as assessed by computed tomography, was not significantly greater in manic-depressive cases than in neurotic patients, but 19% of manic-depressive cases had ventricular brain ratios (VBR) more than two standard deviations above the neurotic mean. Few correlates of VBR were found in the features of the illness and the treatment given, apart from the fact that in the outpatient sample, there was a significant association between increased VBR and hypothyroidism. Hypothyroidism was relatively common in this sample, but was treated and not associated with cognitive impairment. There was no relationship between lithium administration and VBR.

Postmortem evidence of structural brain changes in schizophrenia. Differences in brain weight, temporal horn area, and parahippocampal gyrus compared with affective disorder.

The brains of 232 patients with a case-note diagnosis of schizophrenia or affective disorder who died in one mental hospital over a period of 22 years were weighed, and were assessed in a coronal section at the level of the interventricular foramina. From this sample were eliminated the brains of patients whose illnesses did not meet the Washington University criteria for a diagnosis of definite schizophrenia or primary affective disorder and those brains that showed significant histopathologic evidence of Alzheimer's-type change or cerebrovascular disease. This left a sample of 41 patients with schizophrenia and 29 patients with affective disorder. With age, sex, and year of birth controlled for, the brains of the patients with schizophrenia were 6% lighter, had lateral ventricles that were larger in the anterior (by 19%), and particularly in the temporal, (by 97%) horn cross section, and had significantly thinner parahippocampal cortices (by 11%). The findings provide postmortem confirmation of reports of ventricular enlargement in radiological studies and suggest that such enlargement is associated with tissue loss in the temporal lobe. The changes in schizophrenia were of a lesser degree than those seen in a sample of brains of patients with Alzheimer's-type dementia and Huntington's chorea.

Cognitive style, cortical function, and electroconvulsive therapy.

Performance on the rod and frame test (RFT) was measured over three separate occasions in three groups of 20 depressive patients and a nonpatient control group. Depressive patients were selected into three groups according to whether they had been prescribed one of three forms of treatment: bilateral electroconvulsive therapy (ECT), nondominant unilateral ECT, or a course of antidepressant drugs. The RFT was administered on three occasions: before treatment, 1 week after completion of treatment, and at 3 months follow-up. The control group received no treatment, but were tested at comparable periods. The RFT was scored as mean absolute error and also as separate frame-dependent, rod-dependent, and constant error components. All depressive groups showed improved error measures post-treatment. The two ECT groups showed less frame dependence post-treatment than the drug group. The group receiving bilateral ECT showed a greater decrease in the mean error of performance than the unilateral group. Right-sided unilateral ECT affected frame dependence in patients who were initially frame independent, rather than in those who were initially frame dependent. The results indicated that the effect of ECT may depend on a patient's initial pretreatment cognitive style.

EEG coherence, lateral preference and schizophrenia.

The EEG synchrony between hemispheres during cognitive activity differs from that during rest. With common reference recording and a visual imagery task it increases in healthy right-handers and neurotic patients, and it decreases in healthy left-handers and schizophrenic patients. It is suggested that this implies a less lateralized brain organization in schizophrenia which may account for the often reported association with left-handedness. When associated with impaired corpus callosum transmission, it may contribute to the disturbed behaviour and thought processes in this condition.

EEG coherence analysis and field dependence.

The sensitivity of EEG coherence analysis was examined by comparing two groups of subjects that differed on a measure of information processing style. The psychological theory of field-dependence was combined with a physiological model for interpreting the EEG and led to the prediction that field-dependent subjects would have lower alpha band coherence than field-independent subjects. This was empirically supported. The results also demonstrated a negative linear correlation between field-dependence and EEG coherence during an eyes-closed 'resting' condition. Under this condition the more field-dependent a subject was, the lower their coherence tended to be. These results supported the hypothesis that EEG coherence analysis may be a sensitive measure of the EEG correlates of cortical functioning.