Binge-Eating disorder (BED) is a significant public health problem that co-occurs with obesity but also conveys additional risk for psychological disorders above that of obesity alone. Little is known about the neurobiology of BED. The proposal will contribute to the elucidation of a model of the neurocircuitry of BED by investigating neural responses to reward. BED is postulated to be a distinct pathway to obesity but unlike obesity is associated with hyperactivation of the food reward brain regions during high-calorie food consumption. BED results in weight gain and, with the off-set of loss-of-control binge-eating, eventual underarousal of the food reward system as seen in obesity. This study will be the largest to examine if BED is neurobiologically distinct in reward response from individuals without eating disorders when weight status is controlled for. This study will be the first to examine both anticipatory and consummatory response to food reward as well as extend this examination to non-food reward response in BED (Primary Aim). This study will enroll four groups of: obese BED, non-BED obese, normal-weight BED, and normal-weight non-BED to fully dissociate obesity and BED status. All will be administered 3 functional magnetic resonance neuroimaging tasks. The Primary Hypotheses are that BED subjects compared to non-BED groups will exhibit hyperactivation in: (1) the medial orbitofrontal cortex during the Pictures Task (food anticipation);(2) the striatum during the Milkshake Task (food consumption);and (3) the striatum during a Guessing Game Task (non-food reward). Exploratory Aims will examine what moderates neural responses to reward in BED: behavioral disinhibition and/or a genetic vulnerability to reward sensitivity. Our multi-method approach drawing upon a multidisciplinary team will provide novel pilot data to challenge and enhance our scientific understanding of the reward pathways in BED and to inform our understanding of obesity. The data from this study will be utilized for a future larger study. The study has important implications for BED as a DSM-V diagnostic entity distinct from obesity as well as identifying neural or genetic biomarkers to improve the treatment of BED and / or obesity. This may include the development of treatments to promote both binge-abstinence and weight loss, better prognostic indicators of outcome and more personalized treatments.
Binge-eating disorder (BED) is a significant public health problem. This proposal will provide novel pilot data to investigate neural responses to reward in BED and to elucidate a model of the neurocircuitry of BED. This study aims to examine the reward system in obese BED compared to normal-weight BED, obese non-BED,and normal-weight non-BED groups utilizing functional magnetic resonance imaging.
