0185 N2 Sleep Spindle Activity is Associated with Better Next-Day Emotion Regulation in Healthy Children

Abstract

Abstract Introduction Children's day-to-day mental health is dependent on adequate quantity and quality of sleep, but far less is known about the microstructural sleep features that support emotional functioning in children. NREM sleep spindles (rhythmic EEG oscillations between 10 and 15 Hz) are closely linked with intellectual abilities and cognitive processing, and have also been shown to relate to children’s emotional behavior, both concurrently and longitudinally. For example, socially-anxious youth showed reduction in sleep spindle activity compared to healthy controls, which correlated negatively with subjective reports of arousal in response to negative images (Wilhelm et al., 2017). In younger children, greater NREM 2 spindle density was associated with greater prosocial behavior concurrently and fewer behavioral and social problems one year later (Mikoteit et al., 2012; 2013). However, studies in pediatric samples are limited overall and haven’t examined spindles in relation to objective measures of emotion regulation. Methods We examined relationships between spindle activity during NREM stage 2 (N2) and next-day subjective and objective emotional responses among N=26 healthy children, 7-11 years old. Children completed a full-night of at-home PSG monitoring (10hr sleep opportunity) followed by two in-lab tasks. In task 1, children rated arousal/reactivity in response to negative images from the International Affective Pictures System (IAPS). In task 2, respiratory sinus arrhythmia (RSA) was measured while children were directed to suppress all facial expressions of emotion (i.e., regulate emotional responses to negative content) while watching negatively-valenced movie clips. All analyses controlled for total sleep time on PSG night and RSA analyses controlled for a resting baseline period. Results Greater C3 spindle count (r = .51, p < .05) and density (r = .53, p < .05) were significantly associated with less child-reported arousal towards negative images. Greater F3 peak spindle frequency was positively associated with higher RSA during negative movies (r = .54, p < .05), suggesting better regulatory control of emotional responses to correspond with greater spindle peak frequency. Conclusion Together with previous data, our findings suggest that sleep spindle activity may partially reflect children’s capacity to regulate emotional responses in relation to stressful situations, thereby potentially reducing risk of mental health problems. Support (If Any)