Exploring effects of single-session anodal tDCS over the inferior frontal gyrus on responses to food cues and food cravings among highly disinhibited restrained eaters: A preliminary study

According to the hedonic-inhibitory model, overeating occurs when active inhibitory capacities mediated by the prefrontal areas are overridden by hedonic-eating motivation mediated by the mesolimbic reward system. The inferior frontal gyrus (IFG) has a crucial role in inhibiting hedonic-cues response yet transcranial direct current stimulation (tDCS) studies have emphasized the dorsolateral prefrontal cortex (DLPFC), to the neglect of other executive network regions including the IFG. Therefore, we investigated modulating effects of single session tDCS over the right IFG on behavior response inhibition to external food cues and subjective food cravings among highly disinhibited restrained eaters (REs), a group susceptible to overeating and overweight. Within a randomized blinded between-groups design; participants (N = 57) received a single session of real or sham tDCS over the right IFG. Compared to peers in the sham condition, those who received tDCS stimulation showed higher levels of response inhibition toward external food cues on a post-intervention stop-signal task. Conversely, stimulation had no effects on subjective food cravings. Overall, results suggested tDCS targeting the right IFG has potential utility in treating disinhibited REs. However, because effects were isolated to increasing response inhibition to external food cues, follow-ups are needed to evaluate whether multi-session tDCS targeting this area has effects that extend to subjective food cravings.