Poster D18, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
Early and late inhibitory processes for emotional words: An ERP investigation
Regard Booy1, Mario Liotti1; 1Simon Fraser University
Results from the Negative Affective Priming (NAP) task suggests inhibition of emotional material is dysregulated at both early and late stages of processing in depression. However, it is not yet clear if and how positive and negative material may be differentially affected. In the present study, 46 female undergraduates completed a modified version of the NAP task while continuous EEG was recorded. The NAP task requires subjects to indicate the valence of a target word, while simultaneously ignoring a distractor. At analysis, two trial types are identified; ignored repetition trials (IgnRep; the previous distractor and current target are valence congruent) and control trials (the previous distractor was neutral). Two ERP components were examined; the Early Anterior Positivity (EAP; 190-260ms) and the Late Posterior Potential (LPP; 500-700ms). The EAP is thought to index automatic, bottom-up attentional capture, while the LPP is indexes the amount of working memory resources allocated to later, top-down processing. IgnRep trials for negative words elicited a significantly larger EAP compared to control trials. Within the LPP epoch, mean amplitude to IgnRep trials was significantly larger compared to control trials for positive words. Interestingly, both IgnRep and control trials for negative words elicited a large LPP. This suggests that negative words capture attention more readily possibly as part of a threat detection system. As a result, working memory resources may be employed to maintain a balance between positive and negative material at later stages.
Topic Area: EMOTION & SOCIAL: Emotion-cognition interactions