Satiety modulates reward processing in food addiction: Evidence from event-related potentials

This study investigates the neural correlates of reward processing deficits in food addiction (FA), focusing on the anticipation and feedback phases under different metabolic states. Fifty-four participants (individuals with FA and healthy controls, HC) completed a food and monetary reward task during hungry and satiated states, with electroencephalography (EEG) recording. We specifically measured two event-related potentials (ERPs) associated with anticipation and feedback of reward: Stimulus-Preceding Negativity (SPN) and Feedback-Related Negativity (FRN). In addition, Yale Food Addiction Scale (YFAS) scores assessed addiction severity. Repeated-measures ANOVA and correlation analyses examined group differences and neural-behavioral associations. Behavioral data showed heightened food reward anticipation in individuals with FA during satiety. Participants with FA exhibited larger SPN for food rewards in the satiated state compared to HC, indicating persistent reward anticipation, while FRN was attenuated across both metabolic states in the FA group, reflecting persistent feedback deficits. Monetary rewards showed no group differences between HC and FA. The FRN amplitude correlated with YFAS scores, linking feedback impairment to addiction severity. These results highlight that FA is characterized by food-specific reward processing deficits, particularly exacerbated in satiety. Impaired FRN emerged as a key ERP marker of these deficits and correlated with addiction severity. These findings underscore the critical role of dysregulated reward feedback processing in FA, offering FRN as a potential target for diagnostic and therapeutic interventions.