Perceived Social Support and Children's Physiological Responses to Stress: An Examination of the Stress-Buffering Hypothesis

Objective The current study aimed to examine the stress-buffering effect of children's perceived social support on their hypothalamic-pituitary-adrenocortical axis and autonomic nervous system reactivity to an acute laboratory stressor. Methods A sample of 150 children (aged 9-13 years, mean [standard deviation] age = 10.69 [0.93] years, 74 girls) reported perceived social support, stressful life events, and underwent the Modified Trier Social Stress Test, during which six saliva samples were collected. A two-piece multilevel growth curve model with landmark registration was used to detect trajectory differences in the reactivity and recovery phases of the stress response and account for individual variation in the timing of poststressor peak hormone concentrations. Results The interaction between stressful life events and perceived social support significantly predicted poststressor peak cortisol levels (beta = 0.0805, SE = 0.0328, p = .015) and cortisol recovery slope (beta = -0.0011, SE = 0.0005, p = .040). Children with more life events and low social support exhibited the lowest poststressor peak cortisol levels and the flattest cortisol recovery slope. In contrast, children high in stressful life events and high in social support displayed cortisol response profiles more similar to those of children with low stressful life events. Conversely, there were no statistically significant two-way interactions of stressful life events and perceived social support on salivary alpha-amylase parameters (i.e., poststressor peak [p = .38], reactivity slope [p = .81], and recovery slope [p = .32]). Conclusions These results provide preliminary evidence for the buffering effect of children's perceived social support on the association between life stress and hypothalamic-pituitary-adrenocortical axis response profiles.