When the selfish suffer: evidence for selective prosocial emotional and physiological responses to suffering egoists

Prosociality is fundamental to social relationships, but providing it indiscriminately risks exploitation by egoists. Past work demonstrates that individuals avoid these risks through a more selective form of prosociality, cooperating less and sharing fewer resources with egoists (e.g. Axelrod & Hamilton, 1981). The evolution of cooperation. Science, 211(4489), 1390-1396). We extend this work to explore whether individuals experience reduced prosocial affective and physiological responses to egoists in situations where they are suffering. In two studies, participants learned of a target's egoistic or non-egoistic traits, and then encountered the target suffering. Suffering egoists evoked less compassion in others than non-egoists and elicited physiological responses that diverged from patterns associated with compassion and social engagement (reduced heart rate and greater respiratory sinus arrhythmia activity). Participants' feelings of distrust toward egoists explained these attenuated emotional and physiological responses. These results build upon studies of prosocial behavior by suggesting that individuals experience reduced prosocial emotional and physiological responses toward suffering egoists.