Arousal-based pupil responses during value expectation and outcome evaluation show different correlation patterns with EBR.
(A): Reward and loss expectation elicited identical pupil responses. (B): Reward expectation correlated significantly with EBR, indicating that reward expectation elicits stronger pupil dilation in individuals with low compared to high EBR. (C): Violated reward and loss expectations resulted in unsigned, transient pupil dilation. No dilation differences were observed between U- and U+ responses, which was reflected in the ΔU response. (D): ΔU correlated significantly with EBR, indicating that the variability in the ΔU response related to individual differences in EBR (E & F): A median split on individual differences in EBR visualizes the correlation between ΔU and EBR, where pupil dilation response patterns to unpredicted outcomes reversed for individuals with low compared to high EBR. Horizontal significance designators indicate time points where p<0.05. Error bars are standard error of the mean. Statistics based on cluster-based (correlation) permutation tests, n = 1000.