Hypofrontality in schizophrenia: a review of the evidence

This paper reviews the possible role of frontal lobe dysfunction in the pathophysiology of schizophrenia. Pathological, computerized axial tomography (CAT) scan and magnetic resonance imaging (MRI) studies have indicated that a substantial number of schizophrenic patients show structural abnormalities in the frontal lobe areas and other parts of the brain. In some cases, these changes can be correlated with negative symptoms. Attempts to study frontal lobe function with neuropsychological tests, topographic EEG, cerebral blood flow (CBF) and positron emission tomography (PET) scans have also indicated that a substantial number of schizophrenics show abnormalities compared to normal controls. However, these abnormalities can be seen to some degree in other conditions. As well, patients early in the course of their illness tend not to show frontal lobe functional abnormalities. The implications of these findings for current theories of schizophrenia are discussed.