Neurocognitive Correlates of Food-Related Response Inhibition in Overweight/Obese Adults.

Response inhibition is thought to play a critical role in the manifestation and maintenance of obesity. The study aimed to investigate the behavioral and neural correlates of food-related response inhibition in overweight/obese adults (OWs). In total, 23 normal-weight adults (NWs) and 21 OWs were recruited to investigate food-related response inhibition. Participants underwent food no-go and flower no-go tasks, during which event-related potentials (ERPs) were recorded. The food no-go task was used to explore the food-related response inhibition, and the flower no-go task was used to explore the general response inhibition. P2, N2a, N2b, and P3 components were investigated. We found that even though OWs experienced more guilt than did NWs, OWs were preoccupied with food and lacked control over their eating (as measured by food-craving questionnaire-trait) compared with NWs (all ps < 0.05). ERP analyses showed that P2 amplitudes were significantly greater and N2a amplitudes were lower in OWs than in NWs in the two tasks; in addition, N2b amplitudes were lower and P3 amplitudes were greater in OWs than in NWs in the food no-go task. Moreover, body mass index was significantly related to food N2a, food N2b, and food P3. The findings indicate that OWs may be less efficient in conflict monitoring and may need more response inhibition resources to inhibit their automatic response to food-related stimuli. Further studies are needed to develop intervention strategies to enhance response inhibition in OWs.