The social buffering of the hypothalamic-pituitary-adrenocortical axis in humans: Developmental and experiential determinants.

Social buffering, a subset of social support, is the process through which the availability of a conspecific reduces the activity of stress-mediating neurobiological systems. While its role in coping and resilience is significant, we know little about its developmental history in humans. This brief review presents an integrative developmental account of the social buffering of hypothalamic-pituitary-adrenocortical (HPA) stress reactivity in humans, from infancy to adulthood. During infancy, parents are powerful stress-regulators for children, but child temperament also plays a role and interacts with parenting quality to predict the magnitude of stress responses to fear or pain stimuli. Recent work indicates that parental support remains a potent stress buffer into late childhood, but that it loses its effectiveness as a buffer of the HPA axis by adolescence. Puberty may be the switch that alters the potency of parental buffering. Beginning in middle childhood, friends may serve as stress buffers, particularly when other peers are the source of stress. By adulthood, romantic partners assume this protective role, though studies often reveal sex differences that are currently not well understood. Translational research across species will be critical for developing a mechanistic understanding of social buffering and the processes involved in developmental changes noted in this review.