Avoiding Pain to Others Motivates Effortful Prosocial Behavior.

Protecting others from harm is critical for societal well-being, but is often effortful. How individuals weigh the costs of exerting effort against the benefits of avoiding harm to others is currently unknown. To fill this gap, we investigated how individuals decide to exert physical effort to reduce painful shocks delivered to themselves and another person. Results showed that individuals are similarly motivated to incur effort costs to reduce their pain and the pain of another person. Specifically, we found no credible evidence that participants' willingness to put in effort and the force they exerted to reduce pain differed when helping the other person versus themselves. Further, we showed little credible evidence of a difference in discounting of pain reduction by effort between self- and other-related choices. These results contrast with prior research indicating that individuals are less motivated to exert effort to gain (or avoid losing) monetary rewards for others than themselves and demonstrate that protecting others from harm shifts individuals' effortful behavior from prosocially apathetic to prosocially motivated. Our findings shed light on the motivational processes underlying interpersonal harm avoidance and effortful prosocial behavior and highlight the importance of the type of benefit at stake for motivating prosociality.