Anterior cingulate gyrus dysfunction and selective attention deficits in schizophrenia: [15O]H2O PET study during single-trial Stroop task performance.

OBJECTIVE: Attentional deficits are a prominent aspect of cognitive dysfunction in schizophrenia. The anterior cingulate gyrus is proposed to be an important component of frontal attentional control systems. Structural and functional abnormalities have been reported in this region in schizophrenia, but their relationship to attentional deficits is unknown. The authors investigated the function of the anterior cingulate gyrus and the related neural systems that are associated with selective attention in patients with schizophrenia.
METHOD: While subjects performed multiple blocks of a single-trial Stroop task, [15O]H2O positron emission tomography scans were obtained. Fourteen patients with schizophrenia were compared with 15 normal subjects matched for age, gender, and parental education.
RESULTS: The patients with schizophrenia responded at the same rate but made more errors in color naming during the color-incongruent condition. Consistent with the authors' hypothesis, patients with schizophrenia showed significantly less anterior cingulate gyrus activation while naming the color of color-incongruent stimuli.
CONCLUSIONS: Patients with schizophrenia fail to activate the anterior cingulate gyrus during selective attention performance. This finding adds to the understanding of the functional significance of the structural and metabolic abnormalities in schizophrenia that have been previously reported in this region of the brain.