Abstract
We report a functional magnetic resonance imaging (fMRI) study of healthy adult participants who completed a demanding Go/NoGo task. The primary purpose of this study was to delineate the neural systems underlying successful and unsuccessful response inhibition using a large sample (N=102). We identified a number of regions uniquely engaged during successful response inhibition, including a fronto-parietal network involving the anterior cingulate, supplementary motor areas, lateral and inferior prefrontal regions, and the inferior parietal lobule. Unique hemodynamic activity was also noted in the amygdala and in frontostriatal regions including the inferior frontal gyrus and portions of the basal ganglia. Also, contrasts were defined to explore three variants of hemodynamic response allowing for more specificity in identifying the underlying cognitive mechanisms of response inhibition. Addressing issues raised by prior small sample studies, we identified a stable set of regions involved in successful response inhibition. The present results help to incrementally refine the specificity of the neural correlates of response inhibition.