Neuronal activity and reward processing in relation to binge eating

Abstract

Purpose of review Studies increasingly show the importance of reward processing in binge eating and provide evidence of associated changes in the neurobiological reward system. This review gives an up-to-date overview of the neurobiological substrates of reward processing subconstructs in binge eating. Neural findings are linked to different behavioral theories and the clinical relevance is discussed. Recent findings Increased neural responses in the orbitofrontal cortex, anterior cingulate cortex as well as striatum during anticipation and receipt of food rewards are found in association to binge eating. Increased model-free learning is also found and associated with altered brain reward reactivity. Data in rest report reduced striatal dopamine release and lower frontostriatal connectivity. Mechanisms of onset of binge eating are less clear, but specific personality traits, related to frontostriatal dysconnectivity, probably increase the risk of binge eating onset. Summary Both structural and task-based imaging studies show differences in the neurobiological reward system in binge eating. These changes are linked to specific reward processing, such as altered reward responsiveness to food cues, reinforcement learning, and habitual behavior. Findings are lined with different behavioral theories of binge eating, and a staging model is described, from onset to full illness development. Understanding the specific underlying aberrant reward mechanism in binge eating, associated with different stages of the illness, enables caregivers to focus their treatment more precisely.

Obesity surgery and neural correlates of human eating behaviour: A systematic review of functional MRI studies

“…Therefore, an important factor that may contribute to the variability in response of food cue reactivity to bariatric surgery is inter-individual differences, not only in the eating behaviours discussed above (external and disinhibited eating, or dietary restraint), but also the overlapping presence or symptoms of ‘food addiction’, emotional eating and binge eating disorder, which may not only influence clinical outcomes after bariatric surgery ( Ivezaj et al, 2017 , Athanasiadis et al, 2021 , Kops et al, 2021 , Cohen and Petry, 2023 ), but also food cue reactivity and hedonics both at baseline and follow-up ( Bohon et al, 2009 , Chechlacz et al, 2009 , Gearhardt et al, 2011 , Finlayson, 2017 , Schulte et al, 2019 , Constant et al, 2020 , Som et al, 2022 , Vrieze and Leenaerts, 2023 ). This will be contributed to by variability in the effects of different surgeries on eating behaviours and the degree/nature of their pre-, peri- and post-operative psychological and dietary management which will vary between centres.…”