The effect of food-related stimuli on inhibition in high vs. low restrained eaters.

Restrained eaters constantly limit their eating behavior to avoid gaining weight. Previous research suggests that fundamental deficits in response inhibition might play a role in the development of disinhibited eating among restrained eaters. The current study focuses on the impact of food vs. non-food stimuli on response inhibition in high vs. low restrained eaters. Seventy-five females (38 high and 37 low restrained eaters) completed a novel food stop-signal task in which they were required to discriminate between food and non-food images while inhibiting their response when a stop-signal appeared. The ability to inhibit a response was assessed separately for food and non-food trials, which were used to assess specific inhibition to food and general inhibitory abilities, respectively. Overall, high restrained eaters exhibited poorer response inhibition to non-food stimuli compared to low restrained eaters. Most importantly, high restrained eaters were better able to inhibit a response following presentation of food compared to non-food stimuli. In contrast, low restrained eaters were better at inhibiting a response following non-food compared to food stimuli. We suggest that this pattern is due to fast and strong activation of the response inhibition system in high restrained eaters when facing food stimuli - an activation which might later lead to a paradoxical breakdown of control over eating behavior.