a version of the flanker task, but does not affect N2 amplitude. Recently, Crego et al. (2009) reported larger N2 amplitudes for young binge drinkers in a visual working memory task and interpreted it as a result of higher attentional efforts in this group. Similar findings of increased N2 amplitude in alcoholics have also been reported (Olbrich et al., 2000; Olbrich et al., 2002). Swick and Turken (2002) reported that a patient with a rare focal lesion of left ACC exhibited substantially reduced ERN amplitude after incorrect responses on a version of the Stroop paradigm, but greatly increased N450 amplitude on correct conflict trials. Hogan et al. (2006) reported diminished response-locked correct-response negativity (CRN) and ERN in patients with frontal white matter lesions whereas stimulus-locked ERP components (N2 and P3) were not significantly affected by the presence of lesions. Using a computational simulation model, Yeung and Cohen (2006) have replicated Swick and Turken's findings, and suggested that the ERN and N2 are sensitive to different aspects of task processing, where lesion-induced attentional deficits led to impaired task processing (i.e., reduced ERN amplitude) while also causing increased processing of irrelevant stimulus information (i.e., increased N2 amplitude). Thus, findings are equivocal, and
