Too Stressed to Sleep: Autonomic Nervous System Reactivity and Sleep in Adolescents

Abstract

The purpose of the present study was to investigate relations between autonomic nervous system (ANS) reactivity across its parasympathetic and sympathetic branches and multiple sleep parameters in adolescence. Participants were 244 adolescents (Mage = 15.79 years old, SD = 9.56 months; 67.2% White/European-American, 32.8% Black/African-American). Parasympathetic activity was indexed by respiratory sinus arrhythmia withdrawal (RSA-r) and sympathetic activity was indexed by skin conductance level reactivity (SCL-r), which were examined during the day in the lab and in response to a moderate stressor (the star tracing task). Sleep was examined with actigraphs in adolescents’ homes for 7 consecutive nights and the following sleep parameters were derived: minutes, efficiency, and long wake episodes (LWE). Linear and non-linear relations between RSA-r or SCL-r and sleep as well as the moderating role of child sex in all examined relations were explored. Regression analysis showed that more RSA withdrawal (lower levels during task than baseline) was associated with shorter sleep, and more SLC-r (higher levels during task than baseline) was associated with shorter sleep, lower sleep efficiency, and more LWE. Assessments of quadratic effects indicated that an average level of SCL-r was associated with longer sleep, while low and high levels of SCL-r were associated with shorter sleep. Additionally, the negative association between SCL-r and sleep efficiency and the positive association between SCL-r and LWE accelerated as SCL-r increased. Finally, moderation analysis showed that associations between RSA withdrawal and SCL-r and sleep minutes and efficiency were significant only for boys. In general, results illustrate that higher daytime physiological reactivity (increased RSA withdrawal and SCL-r) is negatively associated with sleep duration and quality for adolescents.