The most prominent behavioral impairments in schizophrenia involve the failure to control thoughts and actions. Previous research has demonstrated three areas in which these failures of cognitive control are clearly exhibited: 1) selective attention in the face of distraction; 2) inhibition of inappropriate responses; and 3) strategic regulation of behavior based on situational demands. Moreover, these behavioral impairments have been linked to disturbances in three distinct brain regions-- dorsolateral prefrontal cortex (DLPFC), ventral prefrontal cortex (VPFC),and anterior cingulate cortex (ACC). However, progress cannot be made in understanding the specific pathophysiology associated with these brain regions in schizophrenia until their functional contributions to normal cognitive control are better understood. The purpose of this project is to test a new theory regarding the distinct roles of DLPFC, VPFC, and ACC in cognitive control, using a parallel strategy of functional brain imaging in healthy controls and behavioral testing in patients with schizophrenia. Brain activity will be monitored in controls, using functional magnetic resonance imaging (fMRI), during performance of a behavioral task that selectively engages attention, inhibition, and performance monitoring processes. The high degree of experimental control afforded by the task will permit a direct test of several novel and theoretically motivated predictions, while also enabling association of activity in DLPFC, VPFC, and ACC with particular task components. Behavioral testing of patients with schizophrenia in the identical task paradigm will allow for sensitive detection of specific impairments in cognitive control, as well as paving the way for future fMRI studies examining their biological basis.
NARSAD Independent Investigator Award (Braver)