Social buffering of stress responses in nonhuman primates: Maternal regulation of the development of emotional regulatory brain circuits

Abstract

Social buffering, the phenomenon by which the presence of a familiar individual reduces or even eliminates stress- and fear-induced responses, exists in different animal species and has been examined in the context of the mother–infant relationship, in addition to adults. Although it is a well-known effect, the biological mechanisms that underlie it as well as its developmental impact are not well understood. Here, we provide a review of evidence of social and maternal buffering of stress reactivity in nonhuman primates, and some data from our group suggesting that when the mother–infant relationship is disrupted, maternal buffering is impaired. This evidence underscores the critical role that maternal care plays for proper regulation and development of emotional and stress responses of primate infants. Disruptions of the parent–infant bond constitute early adverse experiences associated with increased risk for psychopathology. We will focus on infant maltreatment, a devastating experience not only for humans, but for nonhuman primates as well. Taking advantage of this naturalistic animal model of adverse maternal caregiving, we have shown that competent maternal care is critical for the development of healthy attachment, social behavior, and emotional and stress regulation, as well as of the neural circuits underlying these functions.

Keywords:

• Social buffering
• Nonhuman primates
• Stress reactivity
• HPA axis

We want to thank Anne Graff, Alison Grand and Richelle Scales for technical assistance with experimental procedures used to generate some of the findings presented here.

Additional information

Funding

This work was supported by NIMH grants P50 MH078105 and F31 MH086203 (to BRH), NICHD grants HD055255 and HD077623, and NSF conference grant [BCS-1439258] Mar Sanchez, Co-Inv. The content is solely the responsibility of the authors and does not represent the official views of the NIMH, NICHD, or the NIH. The project was also supported by the Office of Research Infrastructure Programs/OD (ORIP/OD) P51OD11132 (YNPRC Base grant, formerly NCRR P51RR000165). The YNPRC is fully accredited by the Association for the Assessment and Accreditation of Laboratory Care, International.