Healthy Restrained Eaters Diminish Consummatory Food Reward and Inhibit Prepotent Feeding Responses: An EEG Study

Abstract

Background: Some individuals with modest elevations in dietary restraint exhibit the ability to diminish consummatory and anticipatory food reward. In this paper we aim to identify the underlying mechanisms of food-specific cortical inhibition responses in restrained vs unrestrained eaters. Methods: Restrained (n = 43) and unrestrained eaters (n = 38) completed self-report surveys and a food- vs non-food Stroop task protocol with record of electroencephalography (EEG). Cortical rhythms and EEG ERPs were assessed. Results: Compared to their unrestrained peers, restrained eaters showed several differences in food task-related event-related potential (ERP) waveform presentation: ERP P300 component latency was significantly longer during food image viewing over the left parietal cortex (P3), and the amplitudes of the ERP P300 and LPP components were significantly greater over the right central electrode (C4) whilst responding to Stroop color-word cues. Food task-related conflict cue elicited ERP P300 amplitude correlated positively with eating restraint, and negatively with bioelectrical impedance assessed % body fat. Conclusions: Restrained eaters free of eating pathology attenuate conscious visual food cue processing and show enhanced executive brain functioning during late attentional processing despite the presence of distractor food cues. Our data propose robust executive governance as the primary underlying neurophysiological mechanism by which healthy restrained eaters diminish consummatory food reward and inhibit prepotent feeding responses.