Background: Given that adolescence has been described as a “perfect storm” of sleep loss (Caskadon, 2011), and that adolescence includes increased risk for disorders of emotion dysregulation, it is important to understand how sleep impacts emotion regulation processes on a daily basis. Few studies have objectively monitored sleep in adolescents and tracked naturalistically how that sleep impacts daily emotion and emotion recovery. Indeed, few people have studied the impact of accumulated sleep debt, versus a single night of sleep loss, on emotional reactivity to stress in this population. It is possible that adolescents are resilient to a single night of poor sleep, but that sleep-emotion connections are stronger in the face of multiple nights of poor sleep. There is some evidence that accumulated sleep debt is more detrimental to stress reactivity and mood than a single night of short sleep (Dinges et al., 1997). For example, Hamilton et al (2008) found that mounting sleep debt, not sleep duration, predicted greater next-day negative affect in adults. As the number of days of restricted sleep piles up, managing and recovering from emotional stress may become increasingly difficult. However, there is little work on sleep debt and emotional reactivity to stress in adolescents. In the present study, we tested the effect of sleep debt on emotional reactivity to daily stress using a daily diary study and objective monitoring of sleep.
Methods: High school students (N=89) completed morning and evening surveys, including self-reported positive affect (PA), negative affect (NA), and stress appraisals, each day for two weeks. Participants were instructed to complete their respective survey measures as close to wake time and bedtime as possible every day. Objective measurements of sleep, including total sleep time and sleep debt, were gathered using Fitbit sleep monitoring devices. Sleep debt was operationalized as the number of consecutive days that a participant's Fitbit recorded less than six hours of sleep a night.
Conclusion: We used hierarchical linear modeling to test the relationships between daily stress and NA and PA, and the moderating role of sleep. We first tested whether total sleep time was associated with negative and positive affect changes as daily stress increased. No link was found between total sleep time and daily emotion reactivity. Next, we tested whether accumulated sleep debt across days predicted emotional reactivity to stress. Although there was not an effect of sleep debt on negative emotional reactions to stress, a significant interaction was found between stress and sleep debt in predicting positive affect (b = -.065, SE = .031, t(88) = -2.107, p < .05). The interaction suggested that when sleep debt was high, there is a stronger inverse relationship between same-day stress and evening PA than when sleep debt was low. So when sleep debt was high, teenagers had a harder time maintaining positive emotion in the face of stress. This might be an important aspect of how sleep impacts emotion regulation among adolescents.