Future Directions in the Study of Social Relationships as Regulators of the HPA Axis Across Development

Abstract

Many promising findings support the notion that social relationships can dampen HPA axis stress responses and protect individuals from maladaptive psychological and physical disease states. Despite the public health relevance of this topic, little is known about developmental changes in the social regulation of the HPA system, with most prior research having focused on early childhood and adulthood. This gap is particularly striking with regards to adolescence, an age period when it seems likely that reliance on parents as sources of stress-buffering decreases, even as the security of friends and relationship partners as stress buffers may not yet be certain. Furthermore, we speculate that early life stress or abnormal social experiences may impact the propensity to draw mental and physical health benefits from social relationships, but more empirical support for these ideas is needed. Lastly, research linking social support to cumulative life stress has mostly relied on self-report measures of stress, making it difficult to show that social support impacts the type of chronic stress exposure that is associated with increased allostatic load or “wear and tear” on the body and on psychological functioning. Recent advancements in methodology (e.g., assessing hair cortisol levels) as well as composite measures of allostatic load using biomarkers that capture the activity of multiple neuroendocrine, cardiovascular, immune, and metabolic systems will allow us to ask new questions about the extent to which social relationships can impact cumulative life stress and health.

Stress and depression: old questions, new approaches

“…Also, some individuals appear to be 'sensitized' by experiences such as exposure to adversity in childhood, so that they are more likely to develop depression in response to later-occurring stressors compared to those not exposed or to develop depression at lower levels of exposure [23][24][25]. There is a growing body of research and theory on the ways in which stressful experiences including social relationships sculpt the brain and neuroendocrine systems at different developmental periods from prenatal through adolescence [26][27][28].…”

“…[59]). The quality of this intimate relationship has a powerful effect on infant and child outcomes and HPA axis development, and Hostinar and Gunnar [27] argue that social relationships are regulators of HPA axis functioning, including the ability to benefit from social supports during stress.…”

“…The role of early life stress on HPA axis functioning and brain development contributing to stress reactivity and psychopathology [26][27][28] makes salient the likelihood that effects of the early environment on the developing child are mediated extensively through maternal care (e.g. [59]).…”

Attachment Figure's Regulation of Infant Brain and Behavior

“…The human literature has documented a clear role for the caregiver in regulating the physiological and emotional state of the infant: the infant relies on the caregiver for regulation of basic physiology, ranging from vital functions, such as heart rate and respiration, to emotional regulation, which is reviewed in Hostinar et al (2013). Animal models and translational research have begun to identify the mechanism for this regulation.…”

“…to modulate behavior (Hennessy et al, 2009;Hennessy et al, 2015;Hostinar & Gunnar, 2013;Hostinar et al, 2013;Sanchez et al, 2015;Sullivan & Perry, 2015;Tottenham, Shapiro, Telzer, & Humphreys, 2012).…”