Changes in regional cerebral blood flow due to cognitive activation among patients with schizophrenia

Background The regional cerebral blood flow (rCBF) response to the Wisconsin Card Sort Test(WCST) has been used to assess the functional integrity of the prefrontal cortex in patients with schizophrenia. Aims In this study, patients were divided into two groups according to whether they had made few or many perseverative errors on a modified version of the WCST. A control group consisted of normal volunteers. The groups were then: compared with respect to rCBF response to WCST activation. Method rCBF was measured during administration of a modified version of the WCST and during a card sorting control task, using single photon emission computerised tomography (SPECT). Results Performance of the modified WCST was associated with a widespread and substantial increase in rCBF, particularly in the frontal region. The poorly performing group of patients with schizophrenia showed only a modest increase in rCBF in the left anterior cingulate region. Conclusion Subjects with schizophrenia are able-to respond to specific neuropsychological challenge with activation of the frontal regions. Declaration of interest C.I.O. was funded by the South East Thames Regional Health Authority Locally Organised Research Scheme.