Structural brain abnormalities in male schizophrenics reflect fronto-temporal dissociation
P. W. R. WOODRUFF a1 , I. C. WRIGHT a1 , N. SHURIQUIE a1 , H. RUSSOUW a1 , T. RUSHE a1 , R. J. HOWARD a1 , M. GRAVES a1 , E. T. BULLMORE a1 and R. M. MURRAY a1
a1 Departments of Psychological Medicine and Old Age Psychiatry, Institute of Psychiatry, King's College School of Medicine and Department of Radiology, Guy's Hospital Medical School, London; and Department of Psychiatry, University of Stellenbosch, South Africa
Background. Many studies have separately reported abnormalities of frontal and temporal lobe structures in schizophrenia, but little is known of structural fronto-temporal associations in this condition. We investigated whether male patients with chronic schizophrenia would show abnormal patterns of correlation between regional brain volumes.
Methods. Structural magnetic resonance images of the brain in 42 patients were compared with 43 matched unaffected controls. We explored the pattern of association between regional brain volumes by correlational analyses, and non-parametrically tested for significance of between-group differences by randomization.
Results. The schizophrenics demonstrated significant volume deficits in several brain regions (left temporal lobe and hippocampus, right dorsolateral prefrontal cortex), and significant volume increases in the ventricular system (third ventricle and left temporal horn of the lateral ventricle). Controls demonstrated large positive correlations (r>0·4) between prefrontal and temporal lobe regions. By contrast, inter-regional correlations significantly reduced in schizophrenics included those between prefrontal, anterior cingulate and temporal regions, and between posterior cingulate and hippocampus (P<0·05). The most salient abnormality in patients was a dissociation between prefrontal and superior temporal gyrus volumes (P<0·01).
Conclusions. These results support the existence of a relative ‘fronto-temporal dissociation’ in schizophrenia which we suggest may be due to lack of mutually trophic influences during frontal and temporal lobe development.
Address for correspondence: Dr P. W. R. Woodruff, Department of Psychological Medicine, Institute of Psychiatry and King's College School of Medicine, De Crespigny Park, Denmark Hill, London SE5 8AF.