Developmental Impacts of Sleep on Positive Valence Systems and Socioemotional Functioning during Pre-Adolescence - Project Summary Sleep patterns characterized by truncated weekday sleep followed by weekend recovery sleep (‘social jetlag’) often begin to emerge during pre-adolescence (8-12 years). Research from our team has demonstrated that this sleep pattern adversely impacts positive valence systems (PVS) in ways that elevate risk for depression and other psychiatric disorders. Heightened neuroplasticity and re-organization of reward-related brain regions present during this period of the lifespan likely confer a unique opportunity for prevention and intervention, but research on sleep-affective relations during this vulnerable period of development remains limited. The present set of studies will examine mechanistic pathways between behavioral and neurophysiological (EEG) sleep patterns and PVS in social and non-social contexts during pre-adolescence. Study 1 includes an intensive one- year longitudinal burst design with a non-clinical sample of youth (N = 290; ages 8-12). At three separate assessment waves (6 months apart), participants will complete a 14-day monitoring period including objective sleep using actigraphy, daily video diaries and surveys, passive audio recordings of naturalistic social interactions, and a series of behavioral tasks to assess reward responsiveness, learning, and valuation. This longitudinal study is complemented by Study 2, which includes a separate sample of non-clinical youth (N = 64; ages 10-12) who will complete an experimental protocol using a randomized crossover design. Participants will stay in the laboratory with a friend for two 5-night visits where dyads will simultaneously undergo multiple nights of sleep restriction followed by recovery sleep, as well as 5 nights of healthy sleep. Each evening in the lab, participants will complete surveys and paradigms assessing social and non-social reward responsiveness, learning, and valuation. A daily recorded interaction period with their peer will also be coded for positive social behaviors (approach behaviors, affective synchrony, positive affective expression, and gaze patterns using eye tracking). Participants will also complete polysomnography during each night of the laboratory protocols and changes in sleep EEG (i.e., rapid eye movement sleep) will be examined as a mechanism underlying daytime socioemotional changes. Additional analyses for both studies focus on how biological sex modifies socioemotional vulnerability to sleep patterns. The proposed research addresses multiple critical gaps in scientific knowledge surrounding the impact of sleep on the development of reward systems and social functioning during pre-adolescence. Specific aims leverage RDoC, including PVS and Arousal/Regulatory systems, and support NIMH’s strategic plan to chart mental illness trajectories and determine when, where, and how to intervene. Results will inform theories of these neurodevelopmental processes to better inform prevention and treatment efforts.
