Wisconsin card sort activated blood flow in dorsolateral frontal cortex in never medicated and previously medicated schizophrenics and normal controls

Abstract

and to examine if altered function in these areas is related to dysfunction in subcortical areas, the metabolic activity of cortical and subcortical structures were examined in 11 neuroleptic free DSM-III schizophrenics, four deficit and seven non-deficit, and 12 normal controls using PET imaging with i8F-2-DG. All subjects were examined, at rest, on the NeuroPET, with eyes covered and ears plugged. Glucose utilization (mg glu/lOO gm tissue/minute) was significantly lower in the thalamus of deficit (8.1 + 0.8; mean 5 S.D.) compared to non-deficit patients (10.4 ? 0.7; mean + S.D., p < .Ol); there were no differences in any of the other subcortical areas. Glucose utilization was also lower in multiple regions of the frontal, parietal, and temporal cortices in the deficit patients. In contrast, there were no differences in these areas between the total schizophrenic group and the normal controls. The results suggest that deficit patients may be characterized by decreased thalamic and cortical metabolism, and raise the possibility that these areas mediate the production of deficit symptoms.