The Impact of Incidental Emotion on Prosocial Behavior: A Multilevel Meta-Analysis

Theoretical models suggest that incidental emotions, which are unrelated to the task at hand or situation, could influence prosocial behaviors. However, inconsistent effects across studies highlight the need for a comprehensive quantitative synthesis. Results based on 219 effect sizes from 108 studies (total N = 15,355 participants) revealed: (a) a small but significant overall causal effect of positive emotions on prosocial behavior (after publication bias correction), while negative emotions showed more complex result patterns; (b) beyond valence-based approach, emotions with the same valence but different social functions had distinct effects on prosocial behaviors; and (c) discrete emotions within the same social function clusters, showed varying effects. Overall, these effects are appreciably different not only between clusters but also within clusters. Moderation analyses identified methodological factors explaining heterogeneity in previous findings. We discussed the theoretical and practical implications of these results.