Project Summary Sleep is critical for brain maturation and development in childhood, and for neuronal healing after injury. Traumatic brain injury (TBI) is a common pediatric critical illness affecting more than 50,000 children annually, half of whom suffer acute and chronic sleep wake disturbances (SWD) leading to impaired quality of life. These children also suffer substantial cognitive impairments for many years after injury, particularly in domains of executive function, leading to reduced academic performance and psychosocial dysfunction. Whether sleep disturbances significantly compound these cognitive deficits after TBI remains unknown. Additionally, effective therapies shown to prevent or improve SWD and executive dysfunction among these vulnerable children are lacking. The central hypothesis of this proposal is that SWD are an independent and modifiable risk factor for executive function impairment in children surviving TBI. The objectives of the proposed research are to: 1) Determine the longitudinal association between SWD and executive function after pediatric TBI in a prospective cohort study using both questionnaires and objective measures, 2) Evaluate feasibility and effectiveness of an early melatonin and sleep management intervention started during hospitalization in a single-center randomized controlled trial. Dr. Cydni Williams is a Pediatric Critical Care physician at Oregon Health & Science University where she cares for critically ill children acutely in the pediatric intensive care unit and longitudinally in a critical care follow-up clinic. Her work has identified SWD as an important morbidity affecting more than half of critical care survivors, particularly in the large number of TBI survivors she follows. Her long-term goal is to improve longitudinal outcomes and quality of life through rigorous studies identifying effective interventions to improve sleep disturbances after pediatric critical care, by first evaluating the high risk cohort of TBI survivors. This career development proposal will provide Dr. Williams with experiential and mentored training conducting sleep research, clinical trial methodology, and longitudinal data analyses. This proposal is significant because it addresses the common and debilitating morbidity of SWD that affect thousands of pediatric TBI survivors annually, advances clinical care and research through testing an early sleep management intervention, and aligns with the National Institutes of Health Sleep Disorders Research Plan. This research and multi- disciplinary mentored training will provide Dr. Williams with data and research expertise needed to pursue independent research funding to evaluate SWD in pediatric TBI and other critical illness survivors.