biostudies-literatureHeffner JU.S. Department of Health & Human Services | NIH | National Institute of General Medical SciencesNIGMS NIH HHS1391-1401https://www.ebi.ac.uk/biostudies/studies/S-EPMC8544818biostudies-literatureUnknown5(10)People make decisions based on deviations from expected outcomes, known as prediction errors. Past work has focused on reward prediction errors, largely ignoring violations of expected emotional experiences-emotion prediction errors. We leverage a method to measure real-time fluctuations in emotion as people decide to punish or forgive others. Across four studies (N = 1,016), we reveal that emotion and reward prediction errors have distinguishable contributions to choice, such that emotion prediction errors exert the strongest impact during decision-making. We additionally find that a choice to punish or forgive can be decoded in less than a second from an evolving emotional response, suggesting that emotions swiftly influence choice. Finally, individuals reporting significant levels of deNature human behaviourEmotion prediction errors guide socially adaptive behaviour.PMC8544818P20 GM103645P20GM103645Heffner JFeldmanHall OSon JYfalseEmotion prediction errors guide socially adaptive behaviour.People make decisions based on deviations from expected outcomes, known as prediction errors. Past work has focused on reward prediction errors, largely ignoring violations of expected emotional experiences-emotion prediction errors. We leverage a method to measure real-time fluctuations in emotion as people decide to punish or forgive others. Across four studies (N = 1,016), we reveal that emotion and reward prediction errors have distinguishable contributions to choice, such that emotion prediction errors exert the strongest impact during decision-making. We additionally find that a choice to punish or forgive can be decoded in less than a second from an evolving emotional response, suggesting that emotions swiftly influence choice. Finally, individuals reporting significant levels of de2021-01-01T00:00:00Z2021 Oct2025-05-29T20:02:38.856Z2025-04-06T16:23:46.908ZS-EPMC85448183466730210.1038/s41562-021-01213-6