CEREBRAL BLOOD-FLOW IN SCHIZOPHRENIA - EFFECTS OF MEMORY PROCESSING ON REGIONAL ACTIVATION

Regional cerebral blood flow (rCBF) was measured with the (133)Xenon c learance technique and a high resolution (254 detectors) scanner durin g the performance of a verbal and a facial memory task in 18 patients with schizophrenia and 18 sociodemographically matched controls. Patie nts and controls had comparable resting rCBF, but differed in global a nd hemispheric rCBF changes induced by the memory tasks. Patients had less global increase, which was relatively higher in the left hemisphe re, and this was more pronounced for the verbal task. Although control s showed appropriate laterality changes (L > R for verbal and R > L fo r facial memory) in the midtemporal region, patients failed to show su ch a focal pattern. They did not show appropriate laterality change in the midtemporal region, but instead showed such changes in other regi ons. Patients showed greatest impairment in specificity of verbal reco gnition performance, and this correlated with severity of hallucinatio ns and delusions. This supports a model of left temporal lobe dysfunct ion in schizophrenia.