Similar effect of family history of psychosis on Sylvian fissure size and auditory P200 amplitude in schizophrenic and bipolar subjects

Several cerebral studies point to the non-specificity of structural and fun ctional changes described in schizophrenia and bipolar disorders. Furthermo re, the origin of these changes is still unclear. The present study investi gated the effect of a family history (FH) of psychotic disorders in first-d egree relatives on computed tomographic (CT) measures (ventricular, cerebra l and Sylvian fissure size) and auditory event-related potentials (amplitud es and latencies of peak components in oddball paradigms) in 30 schizophren ic patients and 24 bipolar type I patients. We found a significant correlat ion between FH and the size of the right Sylvian fissure, and between FH an d auditory P200 amplitude. More specifically, the schizophrenic and bipolar patients with negative FH (n = 36) had larger right Sylvian fissures and s maller P200 amplitude than patients with positive FH (n = 18). These findin gs were independent of the specific diagnosis, gender, and age of subjects. Our results suggest some underlying process common to schizophrenia and bi polar I disorder, and they provide support for the continuum view of the no sologic structure of psychotic illness. (C) 2001 Elsevier Science Ireland L td. All rights reserved.