My research program seeks to elucidate neural mechanisms and dietary factors regulating weight gain associated with abnormal sleein rodent models. Clarifying the role of orexin, an integrative endogenous neuropeptide, in mediating weight gain due to disrupted sleeis at the forefront of these studies. While the primary goal is to quantify the energetic cost of and temporal relationshibetween bouts of sleep, physical activity and feeding, establishing the therapeutic efficacy of centrally administered orexin on body weight gain in paramount. These studies are performed by concurrently measuring sleep, physical activity, feeding and energy expenditure in free-living rodents in vivo with high-resolution sensors. Small changes in body composition often precede observable changes in body weight and are clinically significant. Therefore, the laboratory also seeks to investigate the feasibility of a 7T-MRI to quantify whole body composition and brain imaging during central orexin delivery in vivo in collaboration with the University of Arizona Biological Magnetic Resonance Facility.