Biological Embedding of Peer Experiences: The Contribution of Peer Adversity to Stress Regulation

Peer relationships serve as a critical context of development by supporting youths’ fundamental need for relatedness. Although healthy peer relationships can operate as a positive socialization force that enhances development, unhealthy peer relationships can operate as a negative socialization force that undermines development. Youth who are exposed to adversity or marginalized from peer groups not only lose the benefits of having a strong social network but also suffer the risks associated with stress exposure. This chapter focuses on understanding how exposure to peer adversity during the school years upsets normative developmental trajectories and “gets under the skin” to shape biological stress-response systems (including the HPA axis, autonomic nervous system, and immune system) in ways that forecast both proximal and chronic risk for maladjustment. We also consider the possibility, however, that tuning of biological stress-response systems by early adversity may have the potential to foster better adaptation in the context of later positive peer contexts. We describe several developmental conceptual models as a framework for understanding these processes, including stress additive effects, stress amplification, stress sensitization, and stress inoculation. This chapter concludes with future directions for research on the biological embedding of peer adversity and links with developmental outcomes.