N2pc modulations reveal a local filtering mechanism in the human brain

There is considerable evidence linking the N2pc event-related lateralized response with processing of lateral visual targets, usually presented in the presence of visual distractors. It has proven challenging determine to what extent the N2pc reflects mechanisms of target selection versus possible mechanisms of distractor suppression. We present new evidence that is difficult to reconcile both with the distractor-suppression account of the N2pc (which predicts an increase in the amplitude of N2pc in the presence of distractors) and with the finding that N2pc is modulated by the distance between competing stimuli (N2pc is reduced as distance is reduced). In this talk we present new evidence suggesting a mechanism operating on a local spatial scale that can filter out salient distractors, leading to a reduced N2pc, but only under some conditions. The results are
discussed in the context of extant models of attention mechanisms leading to the N2pc component.