Faster, stronger, and more obligatory?A temporal analysis of negative (versus positive) emotional reactions

Evolution-based theorizing has suggested that it may be more mandatory to respond to threatening than rewarding stimuli and considerations of this type are likely to influence the shape and time course of positive versus negative emotional reactions. Hypotheses of this type were examined in four within-subject experiments (total N = 573 undergraduate participants) that assessed moment-by-moment changes in affective feelings in response to appetitive versus aversive emotional images. Algorithms designed to identify peaks and onsets tended to be more successful in identifying negative emotional reactions relative to positive ones. In addition, negative reactions had faster onsets (3 of 4 studies), higher peak amplitudes, and cross-temporal shapes that better approximated prototypes derived by averaging across participants. In the context of a close temporal analysis, negative emotional reactions displayed several features (e.g., faster onsets, higher peaks, and greater matches to prototypes) that suggest higher levels of obligatory responding.