Regional cerebral glucose metabolism in three sets of identical twins with psychotic symptoms

Three sets of young identical twins where at least one had a psychotic episode were assessed in terms of psychiatric and psychological status and integrity of cerebral structure and metabolism. The psychiatric diagnoses for each set were normal/schizophrenia, prodromal/schizophrenia and schizoaffective/schizoaffective. The latter two sets were re-examined two years after the initial assessment. The data are considered from a case study perspective. Reduced cerebral metabolism was found for at least one region on eight of nine scans of patients with a psychotic history. On seven of the nine scans, glucose metabolism in the orbital frontal cortex was reduced. These findings are discussed with respect to previous studies of glucose metabolism in patients with schizophrenia, metabolic similarities found in normal identical twins and the known functional specialization of the orbital frontal cortex.