A little thanks goes a long way: Explaining why gratitude expressions motivate prosocial behavior.

Although research has established that receiving expressions of gratitude increases prosocial behavior, little is known about the psychological mechanisms that mediate this effect. We propose that gratitude expressions can enhance prosocial behavior through both agentic and communal mechanisms, such that when helpers are thanked for their efforts, they experience stronger feelings of self-efficacy and social worth, which motivate them to engage in prosocial behavior. In Experiments 1 and 2, receiving a brief written expression of gratitude motivated helpers to assist both the beneficiary who expressed gratitude and a different beneficiary. These effects of gratitude expressions were mediated by perceptions of…