The neural correlates of emotion processing and reappraisal as reflected in EEG.

Successful reappraisal modulates the impact of emotion-inducing stimuli through reinterpretation of their meaning and decreases subjective emotional experience. Here the question is addressed how the altered emotional experience is related to altered electro-cortical responses, and about the neural mechanisms underlying regulation itself. To this end, we recorded EEG during a cued emotion-regulation paradigm including negative and neutral pictures. Firstly, based on hypothesis-driven analysis of the Late Positive Potential (LPP), we found that the early fronto-centro-parietal LPP (400-1000 ms) increased when passively viewing negative versus neutral pictures. Reappraisal did not decrease this LPP. Instead, only during reappraisal, the emotion effect on the parietal LPP was sustained until the picture offset. Secondly, we applied a localizer approach to uncover reappraisal effects with other spatiotemporal characteristics than the traditional LPP but did not observe such effects. Despite indications of theta oscillations being associated with cognitive and/or affective control, no significant effects were found on theta activity for emotion processing or reappraisal. Our findings suggest that emotion regulation may affect the LPP in several ways, depending on the task design and including affective as well as more cognitive influences. A potential role for theta in emotion regulation remains to be elucidated.