Brain SPECT studies in schizophrenia revealed changes in regional cerebral blood flow (rCBF). The rCBF changes can be detected more accurate by activating tests. The aim of this study was to assess rCBF changes under resting and activation condition by the Raven test. Four control patients (2 male, 2 female, average age 45 years, 26-57 years) and 11 chronic, treated schizophrenic patients (4 male, 7 female, average age: 46 years, 33-56 years) were studied in two HMPAO brain SPECT sessions, 48 hours apart, both resting and during activation task. The images were evaluated visually and semiquantitatively. Under resting condition in the control group, there were no significant rCBF changes. In the Raven activation test, a significantly higher blood flow in the prefrontal region was seen (p < 0.05). The schizophrenic group had a significantly lower rCBF in the temporal region under resting condition (p < 0.05): four patients displayed left, 4 right temporal hypoperfusion and 3 exhibited no rCBF abnormality. In the Raven activation tests 5 patients had prefrontal hyperperfusion, and the remaining 6 patients had no such activation answer. Five patients had hypoperfusion in the temporal region. In our sample, patients with chronic schizophrenia displayed significant temporal hypoperfusion. Moreover the chronic schizophrenic group exhibited a poor response to prefrontal activation compared to the control group.