Prefrontal Dysfunction in First-Degree Relatives of Schizophrenia Patients during a Stroop Task

Abstract

Schizophrenia patients perform poorly on cognitive control tasks and exhibit dysfunction in anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC) during task performance. The unaffected relatives of patients with schizophrenia also exhibit poor cognitive control task performance. However, the relationship between these behavioral deficits in relatives and the integrity of ACC and DLPFC functioning is unclear. In the present study, we used the Stroop color-naming task and event-related fMRI to examine cognitive control task performance and associated neural activity in 17 unaffected relatives of schizophrenia patients and 17 demographically matched healthy controls. On the Stroop task, unaffected relatives exhibited intact post-conflict-related performance adjustments. fMRI data revealed that unaffected relatives exhibited reduced activity in DLPFC but they exhibited intact activity in ACC. These results suggest that DLPFC dysfunction may be related to the genetic risk for schizophrenia as both patients and their unaffected relatives show reduced activity in this region. In contrast, the current results suggest that ACC dysfunction in people with schizophrenia may reflect processes specific to the illness itself.