Frontocentral negativity in electroencephalogram reflects motor response evaluation in humans on correct trials

Recent results suggest that the error-related negativity (ERN/Ne), a negative scalp potential which has so far been associated with error-related processing, is also found for correct responses. This potential is thought to be generated in the anterior cingulate cortex (ACC). To investigate the functional significance of the ERN/Ne, a modified Continuous Performance Task was used. Data analysis was carried out using conventional averaging techniques as well as source localization with low resolution brain electromagnetic tomography (LORETA). Results showed a pronounced negativity associated with correct responses at a frontocentral electrode position, if an expected second imperative stimulus was not presented. LORETA analysis yielded evidence for a source located within the ACC on such trials. Results suggest that a negative scalp potential may be elicited by errorless responses and yield evidence for an evaluative role of the ACC.