PET study of greater visual activation in schizophrenia

OBJECTIVE: The authors tested the hypothesis that photic visual stimuli cause a greater blood flow activation response in subjects with schizophrenia than in normal subjects. METHOD: Eleven medicated patients with schizophrenia and 10 normal subjects were studied with [15O]H2O positron emission tomography to measure perfusion during photic stimulation at four different rates. RESULTS: The activation at three out of four rates of visual stimulation was greater for the patients with schizophrenia than it was for the normal subjects. CONCLUSIONS: Further investigation into the mechanisms of activation during sensory stimulation in schizophrenia is warranted.