Examination of the dynamic relationships of sleep, physical activity, and circadian rhythmicity with neurobehavioral heterogeneity in ADHD - PROJECT SUMMARY The goal of this study is to leverage wearable technology to investigate the dynamic relationships of objectively assessed physical activity (PA; i.e., motor activity during wake time), sleep (SL), and 24-hour circadian rest/activity rhythms (RARs) with heterogeneity in clinical symptoms and neurobehavioral phenotypes in attention-deficit/hyperactivity disorder (ADHD). This project represents a new direction for PI Rosch, building on her program of research on laboratory-based assessment of neurobehavioral functioning in youth with ADHD, to incorporate objective tracking of daily activity/sleep patterns using wrist actigraphy. ADHD is a heterogeneous condition both in terms of clinical presentation (e.g., inattention, hyperactivity, impulsivity, cognitive disengagement syndrome [previously termed sluggish cognitive tempo], emotion dysregulation), neurobehavioral functioning (e.g., cognitive control, delay discounting, and frustration tolerance), and associated structure and function of cortico-subcortical brain circuitry. The factors contributing to this heterogeneity remain unclear, but may be related to PA/SL/RARs which have been shown to separately relate to these clinical symptoms and neurobehavioral functions. Hyperactivity, poor sleep (i.e., longer sleep onset latency, shorter total sleep time, lower sleep efficiency, greater fragmentation and wake after sleep onset), and altered RARs (i.e., weaker, more fragmented, less stable, and more delayed) are common in youth with ADHD. However, there are critical gaps in our understanding of the dynamic (i.e., bidirectional, day-to-day) associations among PA, SL, and RARs in the context of ADHD and associated heterogeneity in clinical symptoms and neurobehavioral functioning, which is needed to better elucidate potential reciprocal associations. Here we propose to address these gaps by examining the dynamic relationships of PA/SL/RARs in children with ADHD by applying novel statistical modeling to objective wrist-actigraphy data gathered in-lab and in natural “free-living” environments. We will do so among a well-characterized, deeply phenotyped local sample of 200 children (8-12 years, 100 diagnosed with ADHD, 100 typically developing controls) using a micro-longitudinal design (i.e., daily assessments of PA/SL/RARs and ratings of behavior and emotion regulation over a 2-week period), and with lab-based assessments of delay discounting, cognitive control, and frustration tolerance, and structural and functional magnetic resonance imaging (MRI). We will also leverage the wrist actigraphy, neurocognitive, clinical, and neuroimaging data from the national community-based Adolescent Brain Cognitive Development (ABCD) cohort of ~4,000 children with actigraphy data collected while “free-living” for up to 3 weeks from children between the ages 9-13 years to conduct complementary analyses. Findings from this project will inform our understanding of the factors contributing to heterogeneity in neurobehavioral functioning and clinical presentation to guide the use of targeted and novel interventions with wearable technology to improve outcomes.
