Shared experiences and prosocial responding: the roles of self-other overlap and perceived emotional synchrony.

Social isolation and difficulties in self-related processing have been linked to a range of psychological challenges. While shared experiences (from collective grief to celebratory events) are known to strengthen social bonds, the mechanisms through which they may beneficially influence self-related cognition and promote prosocial responding remain underexplored. This study investigates perceived emotional synchrony (PES)-the subjective sense of emotional convergence with others during collective events-as a key socioemotional process linking shared experiences to prosocial responding and shaped by self-other overlap (SOO), a core indicator of relational-cognitive connection between the self and others. Across four progressive studies involving both positive and negative emotional contexts, we investigated how shared experiences related to changes in self-perception and subsequent prosocial responding (as an indicator of social function). The results indicated that: (1) sharing an emotional event was associated with greater prosocial responding than individual experience across both positive and negative contexts; (2) in negative emotional contexts, SOO may function as an upstream relational-cognitive state associated with higher levels of perceived emotional synchrony; (3) this cognitive-affective pathway partially accounted for the prosocial effects of shared negative experience. Additional analyses were more consistent with the proposed serial model in which SOO preceded PES than with the reversed serial model. Together, these findings provide a refined account of how shared experiences may promote prosocial responding through cognitive-affective processes that shape the relationship between the self and others.