Prediction strength shapes representations of social judgments and bodily responses to prediction violations

Perceivers' beliefs are critical to form social judgments. However, it remains unclear how the strength of these beliefs or predictions shapes social perception. Here, we investigated how the representation of social perceptions (trustworthiness and likeability ratings) and bodily responses [skin conductance response (SCR)] are modulated by prediction strength, using representational similarity analysis. In two samples of university students, stronger predictions led participants to judge identities as more trustworthy and likeable when identities' facial reactions conformed to their predictions compared to when they were violated. Furthermore, the representational structure of social judgments and SCR were associated with models of prediction fulfillment/violation. More importantly, the similarity between social judgments, SCR representations, and models of prediction violation was positively linked to predictions strength. These results demonstrate that predictions strength modulates how fulfilled/violated predictions influence social judgments and bodily responses, providing new insights into the mechanisms underlying social perception.