PROJECT SUMMARY/ABSTRACT This K23 application aims to support Dr. Ann Haynos her overarching goal of becoming an independent researcher focused on: (a) identifying biological and psychological mechanisms of disordered eating and (b) using this information to inform the development of novel and targeted treatments for eating disorders. The proposed application will strengthen the candidate's abilities to meet these goals by providing advanced training to: (a) develop expertise in theory and assessment of reward mechanisms involved in the cross- diagnostic psychopathology, and to translate this knowledge to research for eating disorders; (b) gain knowledge and skills in neuroimaging necessary to conduct independent research investigating neurobiological underpinnings of disordered eating; and (c) obtain expertise in longitudinal design, methodology, and analysis needed to conduct research examining maintenance of disordered eating. To achieve these goals, an expert team of mentors has been assembled, consisting of primary mentor, Dr. Scott Crow (for training in translational eating disorder research and longitudinal methodology), co-mentors, Dr. Jazmin Camcong (for training in cross-diagnostic reward models), Dr. Kelvin Lim (for training in neuroimaging) and Dr. James Hodges (for training in biostatistics and longitudinal analyses), as well as consultants Dr. Angus MacDonald, III, and Dr. Joanna Steinglass (for training in specific reward and decision-making tasks). As part of this training, Dr. Haynos will complete a project that will identify responses in mesolimbic reward circuitry to typically rewarding stimuli (i.e., entertaining video clips) and disorder-specific stimuli (i.e., restrictive eating cues) among recently weight restored individuals with anorexia nervosa (AN). This study will determine whether responding in mesolimbic circuitry to typical and/or disorder-specific rewards predicts restrictive eating and risk of relapse. AN is associated with extremely poor outcomes and high mortality rates. Although intensive treatment can restore weight to a healthy range, half of individuals with AN relapse within one year of weight restoration. These poor outcomes are due, in part, to the excessive drive towards restrictive eating characterizing this disorder. Little is known regarding the psychobiological mechanisms that maintain restrictive eating and promote relapse. However, there is initial research suggesting that deficit valuation of typically rewarding cues and enhanced valuation of disorder-specific rewards may influence AN symptoms. Therefore, in addition to assisting towards the candidate's training goals, this project will meet a critical need by identifying reward mechanisms predicting restrictive eating and relapse in AN. This knowledge will ultimately promote the development of more effectively targeted treatments promoting long-term recovery from AN.