Independent and interactive effects of tonic respiratory sinus arrythmia and neuroticism on stress related presleep arousal

Sleep quality requires adequate inhibition of mental, behavioral, and physiological processes that perturb the sleep-wake system-a process captured by the construct presleep arousal. The extent to which individual differences in tonic high-frequency heart rate variability (or respiratory sinus arrhythmia [RSA]) and neuroticism predicted stress-related presleep arousal was examined. Eighty four healthy young adults completed measures of presleep arousal prior to and following a laboratory stressor. Neuroticism predicted stress-related changes in cognitive presleep arousal. Tonic RSA moderated the effect of neuroticism on somatic presleep arousal: Neuroticism was associated with poststress increase in somatic presleep arousal only when accompanied by low tonic RSA. These findings demonstrate that identifying individual differences in vulnerability to prolonged stress responses culminating in higher presleep arousal may be pertinent to understanding the development of chronic sleep problems.