Left hypofrontality correlates with blunted affect in schizophrenia.

Regional cerebral blood flow (rCBF) during the resting state was measured using the 133Xe inhalation technique in 39 patients diagnosed as having schizophrenic disorder according to the DSM-III criteria and 30 age- and sex-matched healthy volunteers. All the patients were receiving neuroleptic medication. The bilateral hemispheric mean flow values in the schizophrenic patients decreased significantly and the relative flow distribution reduced significantly only in the left frontal region compared to the controls. The lower the left frontal blood flow in schizophrenics, the more pronounced were the negative symptoms including blunted affect, avolition-apathy and inattention. These results suggest that the negative symptoms in schizophrenics are related to left frontal lobe dysfunction.