Abstract
Emotion-induced blindness (EIB) refers to impaired awareness for items that appear soon after an irrelevant, emotionally arousing stimulus. . In previous research, we used event-related brain potentials (ERPs) to study the mechanisms responsible for EIB. We found that emotional distractor pictures elicited two ERP components that were related to the magnitude of EIB: the N2, which is thought to reflect attentional engagement, and the Pd which appears to index attentional disengagement. The current research investigates whether these components are automatic or require attention. Previous research has produced mixed results on the question of whether the N2 component elicited by negative pictures is affected by attention while the Pd component has not been examined. We addressed the automaticity of these components by requiring participants to perform a multiple object tracking (MOT) task on objects moving in front of a stream of rapidly presented pictures (outdoor scenes and cityscapes). Earlier research showed that MOT abolished awareness for scene pictures appearing in a stream of distractors. Our streams also sometimes contained a "distractor" picture that could be negative (dangerous animals, mutilated bodies, etc.) or neutral (people and animals in nonemotional settings). When observers attended to the picture stream, distractors produced robust N2 and Pd components. In contrast, when they performed the MOT task and attempted to ignore the pictures, the N2 associated with distractors was suppressed while the Pd components increased in amplitude. These results show that the N2 component elicited by distractor pictures is sensitive to attention and is reduced when attention is occupied by another task. In contrast, the Pd component is enhanced when salient distractors are ignored which is consistent with the claim that this component reflects a process responsible for preventing or terminating attentional engagement.
Meeting abstract presented at VSS 2013