Temporal lobe structure by magnetic resonance in bipolar affective disorders and schizophrenia.

Sixteen bipolar and 10 schizophrenic patients, all male, underwent magnetic resonance imaging scans. Areas derived from five coronal sections were measured separately and then summed to obtain an estimate of temporal lobe volumes. Schizophrenics showed a reduction of temporal lobe areas in those sections corresponding to the hippocampal region. This finding was more pronounced for the left side, although no diagnosis by side interaction was present. Temporal lobe volume was also reduced in schizophrenics. When a lateralized difference was present, the right temporal lobe was larger than the left in both patient groups.