Pathogenesis of schizophrenia: Part I. Symptomatology, cognitive characteristics and brain morphology.

The objective of the present study was to provide a pathophysiological model of the development of schizophrenia. The method used was a selective review of recent findings, including those in our own department, concerning the clinical symptoms, cognitive characteristics and morphological brain changes in schizophrenia. A four-syndrome classification was proposed in which 'alienation syndrome' is separated from delusion syndrome. Memory organization deficit in schizophrenia patients was correlated with reduced activation of the left inferior frontal regions. Magnetic resonance imaging and statistical parametric mapping analysis revealed that volume reduction in the temporal lobe was seen in both schizotypal disorder and schizophrenia patients, but schizophrenia patients had additional changes in the medial and dorsolateral frontal regions. In conclusion, a temporo-frontal dual pathology of schizophrenia was suggested.