Partial volume decrease of the thalamus in relatives of patients with schizophrenia.

OBJECTIVE The authors' goal was to compare the thalamic, total brain, and intracranial volumes of patients with schizophrenia, their healthy siblings, and normal comparison subjects. METHOD Magnetic resonance imaging (MRI) brain scans were obtained for 32 same-sex siblings who were discordant for schizophrenia and 32 matched normal comparison subjects. RESULTS Mean total thalamic volume, corrected for total brain volume, was significantly different among affected siblings, unaffected siblings, and comparison subjects. Thalamic volume was smallest in the patients; thalamic volume in their siblings was smaller than that of comparison subjects but larger than that of the patients with schizophrenia. CONCLUSIONS These results suggest that healthy siblings of patients with schizophrenia partially share the thalamic abnormalities of their affected relatives.