REDUCED SUBCORTICAL BRAIN VOLUMES IN NONPSYCHOTIC SIBLINGS OF SCHIZOPHRENIC-PATIENTS - A PILOT MAGNETIC-RESONANCE-IMAGING STUDY

Substantial evidence suggests that nonpsychotic relatives of schizophr enia patients manifest subtle abnormalities in communication, eye move ments, event-related potentials, and neuropsychological processes of a ttention, reasoning, and memory, We sought to determine whether adult relatives without psychosis or schizophrenia spectrum diagnoses might also have structural brain abnormalities, particularly in subcortical regions found to be impaired in patients with schizophrenia itself, Su bjects were six sisters of schizophrenic patients and eleven normal fe male controls, Sixty contiguous 3 mm coronal, T1-weighted 3D magnetic resonance images (MRI) of the entire brain were acquired on a 1.5 Tesl a magnet, Cortical and subcortical gray and white matter was segmented using a semiautomated intensity contour mapping algorithm, Volumes we re adjusted for total brain volumes. Adjusted gray matter subcortical volumes were significantly smaller in relatives than in controls in to tal hippocampus, right amygdala, right putamen, left thalamus, and bra instem, Relatives had significantly enlarged left and total inferior l ateral ventricles, These results, though preliminary, suggest that som e never-psychotic relatives of schizophrenic patients have abnormal br ain structure, If replicated in a larger sample including both sexes, these results would suggest that the genetic liability to schizophreni a is also expressed as structural brain abnormalities. (C) 1997 Wiley- Liss, Inc.