Autonomic and hypothalamic-pituitary-adrenal stress resilience: Impact of cardiac vagal tone

Resilience refers to the ability to cope with stressful events. Variation in the activity of the stress-responsive sympatho-adrenal-medullary and hypothalamic-pituitary-adrenal axes is particularly important for adaptive stress responses and thus may give rise to individual differences in resilience. Here, we investigated whether cardiac vagal tone and adult attachment style are related to psychophysiological stress resilience by exposing a sample of healthy young men and women (n=68) to a laboratory stress test while monitoring autonomic (heart rate, salivary alpha-amylase), hypothalamic-pituitary-adrenal (salivary cortisol), and psychological stress levels. Our results demonstrate that adult attachment style did not influence autonomic, hypothalamic-pituitary-adrenal, or psychological stress responses. In contrast, higher resting cardiac vagal tone was associated with stress-induced increases in cortisol. This suggests a role for sympathetic influences on heart rate regulation in hypothalamic-pituitary-adrenal stress responses, and extends previous observations of a link between vagal tone and stress resilience.