In the midst of rapid globalization, the peaceful coexistence of cultures requires a deeper understanding of the forces that compel prosocial behavior and thwart xenophobia. Yet, the conditions promoting such outgroup-directed altruism have not been determined. Here we report the results of a double-blind, placebo-controlled experiment showing that enhanced activity of the oxytocin system paired with charitable social cues can help counter the effects of xenophobia by fostering altruism toward refugees. These findings suggest that the combination of oxytocin and peer-derived altruistic norms reduces outgroup rejection even in the most selfish and xenophobic individuals, and thereby would be expected to increase the ease by which people adapt to rapidly changing social ecosystems.

Abstract

Never before have individuals had to adapt to social environments defined by such magnitudes of ethnic diversity and cultural differentiation. However, neurobiological evidence informing about strategies to reduce xenophobic sentiment and foster altruistic cooperation with outsiders is scarce. In a series of experiments settled in the context of the current refugee crisis, we tested the propensity of 183 Caucasian participants to make donations to people in need, half of whom were refugees (outgroup) and half of whom were natives (ingroup). Participants scoring low on xenophobic attitudes exhibited an altruistic preference for the outgroup, which further increased after nasal delivery of the neuropeptide oxytocin. In contrast, participants with higher levels of xenophobia generally failed to exhibit enhanced altruism toward the outgroup. This tendency was only countered by pairing oxytocin with peer-derived altruistic norms, resulting in a 74% increase in refugee-directed donations. Collectively, these findings reveal the underlying sociobiological conditions associated with outgroup-directed altruism by showing that charitable social cues co-occurring with enhanced activity of the oxytocin system reduce the effects of xenophobia by facilitating prosocial behavior toward refugees.