Abstract

not-yet-known not-yet-known not-yet-known unknown The brain’s cognitive control mechanisms monitor for changes in the environment, regulating behavior according to internally-represented goals.. Overall, the brain must adapt to changes in the environment and compute the appropriate mental or behavioral action (cognitive flexibility). Cognitive flexibility is frequently measured via voluntary task-switching paradigms, in which participants freely choose when to switch. Remarkably, few VTS studies have probed the neurophysiological mechanism underlying feedback receipt of negative outcomes. In the present study, 51 participants completed a VTS paradigm, consisting of a cue phase where reward cues were shown, the cognitive flexibility task (i.e. letter-number judgment task), and a feedback phase that showed the monetary reward earned following each response: low reward trials ($0.01) and high reward trials ($0.10). We utilize simultaneous eye-tracking and EEG to provide comprehensive neurophysiological indices of cue and feedback processing in reward-based VTS. Eye Tracking results showed increased arousal to high compared to low reward; pupil dilation also tracked feedback outcomes that were surprising, suggesting non-specific salience-related arousal for highly rewarding and highly unrewarding outcomes. EEG results showed a cue-N2 component sensitive to reward cue magnitude, and a late CNV component sensitive to reward vs. no reward cues. We observed increased theta power for outcomes of zero monetary reward compared to low reward feedback, indicating differentiated processing. Taken together, results show differentiated neurophysiological activity for anticipation of high monetary reward and following zero monetary reward. Our work may offer future directions for the role of affect in the processing of negative outcomes.