Evaluation-related frontocentral negativity evoked by correct responses and errors

An event-related potential (ERP) with frontocentral negativity is known to be evoked by error responses, but may also occur on correct response trials. The error-related negativity (ERN) is thought to be generated in the anterior cingulate cortex (ACC). The current study aimed to further elucidate its functional significance as well as its neuronal correlates by directly comparing its amplitude and time course on correct and error trials in a continuous performance task (CPT). Results yielded a frontocentral positive potential preceding correct responses and a high amplitude post-response frontocentral negative potential during conditions involving response competition. To remove potential no-confounding effects of the positive component preceding the motor response, a second experiment was conducted where a red fixation cross served as a cue for potential response competition tendencies. Again, results yielded highest post-response amplitudes on correct trials involving response competition. The positive pre-response potential was eliminated by the visual cue. Interestingly, the cue led to an enhancement of the negative post-response component on trials without response competition. Taken together, the frontocentral post-response negativity might reflect evaluative rather than error-related processing. (C) 2007 Elsevier B.V. All rights reserved.