Effects of food exposure on food-related inhibitory control in restrained eaters: an ERP study

Restrained eaters are likely to overeat when pre-exposed to cues such as the sight, smell, thought or taste of palatable food whereas unrestrained eaters remain unaffected. However, the neurocognitive correlates of inhibitory control to food stimuli after food exposure have not been examined. This study examined food-related and food-unrelated inhibitory control with two variants of Go/No-go task by means of event-related potentials (ERPs) before and after food exposure among restrained and unrestrained eaters. Results revealed that there was a reduction of food-related no-go N2a neural response strength in frontal/frontal-central among restrained eaters compared to unrestrained eaters. Meanwhile, for restrained eaters, food-related no-go P3 amplitude increased significantly after exposure in comparison with baseline, but for unrestrained eaters there was no difference. Importantly, the exposure-induced difference in inhibition between restrained and unrestrained eaters was specific for food-related responses. Results indicated that restrained eaters may be less efficient in monitoring conflict over food-related stimuli and require more cognitive resources to inhibit food-specific responses when exposed to cues of attractive food.