Oxytocin, but not Vasopressin, Increases both Parochial and Universal Altruism

Salomon Israel, Ori Weisel, Richard P. Ebstein, and Gary Bornstein

In today's increasingly interconnected world, deciding with whom and at what level to cooperatebecomes a matter of increasing importance as societies become more globalized and large-scalecooperation becomes a viable means of addressing global issues. This tension can play out viacompetition between local (e.g. within a group) and global (e.g., between groups) interests. Despiteresearch highlighting factors influencing cooperation in such multi-layered situations, theirbiological basis is not well understood. In a double-blind placebo controlled study, we investigatedthe influence of intranasally administered oxytocin and arginine vasopressin on cooperativebehavior at local and global levels. We find that oxytocin causes an increase in both thewillingness to cooperate and the expectation that others will cooperate at both levels. In contrast,participants receiving vasopressin did not differ from those receiving placebo in their cooperativebehavior. Our results highlight the selective role of oxytocin in intergroup cooperative behavior.

February, 2012
Published in: 
Psychoneuroendocrinology (forthcoming)