The proposed K23 career development award will enable Dr. Carmela Alcantara to establish an independent program of research in behavioral medicine that emphasizes the study of sleep deficiency, psychosocial vulnerability, and health. To do so, Dr. Alcantara, a clinical psychologist with expertise in racial/ethnic minority mental health and health disparities, will first require training in health psychology, sleep medicine, an analysis of complex longitudinal data. She has assembled an outstanding multidisciplinary team of mentors to provide training in: (1) health psychology; (2) sleep physiology, epidemiology, and research methods; (3) analysis of complex longitudinal data collected continuously and in real-time; (4) certification in behavioral sleep medicine from the American Board of Sleep Medicine to include didactic and clinical training in sleep assessment, polysomnography testing, scoring, and interpretation; and (5) research dissemination and professional development. The career development plan includes completion of an MPH degree from the Mailman School of Public Health at Columbia University. In this K23, Dr. Alcantara will test the first hypothesis of her lon-term Self-Regulation Model of Sleep and Cardiovascular Health, which proposes that there are bidirectional, within-subject associations between sleep deficiency and self-regulation resources. Over 50 million adults in the United States suffer from sleep deficiency (deficits in th quantity or quality of sleep obtained), independent of sleep disorders. Sleep deficiency is associated with high economic costs, disability, morbidity, and death for millions of Americans. While racial/ethnic and socioeconomic disparities in sleep deficiency are well documented, little research has examined the specific modifiable factors driving sleep disparities. I will conduct an observational study with a single cohort of 80 healthy adults, collecting observational data for 40 days on sleep and performance on self- regulation tasks using unobtrusive and continuous data collection methods. I will use (1) actigraphy to collect data on sleep duration and sleep efficiency, and (2) ecological momentary assessment to monitor self- regulation resources. I hypothesize that sleep deficiency on one night will be associated with less self- regulation resources during the next day; and that less self-regulation during that day will be associated with worse sleep deficiency for that night (a bidirectional or cybernetic, vicious cycle). I will aso explore whether socioeconomic status modifies these associations. Few simple explanatory models with testable hypotheses that lead to targeted interventions to improve sleep have been tested. I propose a simple, intuitive model that, if supported, will lead to simple, scalable interventions focused on self-regulation that could improve sleep, and in turn could provide substantial public health benefit.