Does stress make us more—or less—prosocial? A systematic review and meta-analysis of the effects of acute stress on prosocial behaviours using economic games

Prosocial behaviour is fundamental for our social togetherness. Yet, how acute stress, a common everyday occurrence, influences our behaviours towards one another is still unclear. In this systematic review and meta-analysis, we aimed to quantitatively investigate the effect of experimentally induced acute stress on prosocial behaviours in economic games. We also probed possible moderators to explain differences in findings. We included 23 studies, 77 individual effects, and 2197 participants in the meta-analysis and found no overall differences between stress and control groups in prosocial behaviours (SMD=−0.06), or costly punishment (SMD=−0.11). There were no moderating effects of stressor type, participants’ gender/sex, or the delay from the stressor to the task. However, the potential recipient of the donated money (person vs. charity) and the complexity of the decision did reveal some differences under stress. The results of this meta-analysis suggest that there is currently no clear answer to the question of whether or not stress increases or decreases prosociality. We highlight important open questions and suggest where the field should go next.