Oxytocin and the emergence of individual differences in the social regulation of stress

The ability to use social support to regulate stress is critical to mental and physical health. Here, we posit that the oxytocin system contributes to the variability in individual responses to social support. We first review the evidence that oxytocin is related to both social functioning and stress regulation. We focus on results from molecular genetics suggesting that individual variations in both of these functions are associated with natural variations in the oxytocin receptor gene (OXTR). We then describe research that exploits this natural variation to directly and experimentally test relationships between the oxytocin system, social support, and stress regulation in both infants and adults. On the basis of our findings, we propose a novel theoretical model of how biological processes might interact with psychological beliefs about relationships—even in infants—to affect long‐term patterns of social regulation of stress.