Differential involvement of the anterior cingulate cortex in performance monitoring during a stop-signal task

Electrophysiological and performance measures obtained in a study using the stop-signal paradigm (Van Boxtel, Van der Molen, Jennings, & Brunia, 2001) were used to examine the neural generators of error-related brain potentials. The stop-signal task consists of normal (choice) response trials, which occasionally have to be stopped. However, stopping is not always successful. Erroneous responses to stop signals were carefully matched for motor activity to normal response trials. The difference between normal and error trials was accompanied at the scalp by a sequence of error negativity (ERN/Ne) and error positivity (Pe). Dipole modeling was consistent with generators in the anterior cingulate cortex (ACC) - caudal for the ERN/Ne, and rostral for the Pe. We also found cardiac deceleration on error trials relative to normal response trials, possibly keyed to ACC functioning as well. These results support findings from neuroanatomical, functional brain imaging and animal studies that implicate the differential involvement of the ACC in cognitive and evaluative aspects of executive control.