Frontal activity measured by near-infrared spectroscopy in patients taking different atypical antipsychotic drugs: A cross-sectional study.

Using near-infrared spectroscopy, we examined changes in the concentration of oxygenated hemoglobin ([oxy-Hb]) in the frontal lobe during a verbal fluency task in 20 patients with schizophrenia (10 patients each receiving olanzapine [OLZ] and risperidone [RIS]) and 10 healthy controls. We found that [oxy-Hb] levels in the prefrontal region were higher in the patients receiving OLZ than in those receiving RIS. These results suggest that antipsychotic drugs have different effects on cerebral hemodynamic patterns, which may reflect frontal lobe function. Further studies with a larger sample size are needed to verify our preliminary findings.