Food-Related Stimuli Impair Inhibitory Control in Adults Classified As Overweight to Obese

OBJECTIVES: The present study investigated the influence of food-related cues on motor impulsivity in sedentary adults classified as overweight to obese (BMI 25–45) using a food-specific Go/NoGo Task. Response inhibition was measured by proportion of inhibitory failures to no-go targets (% inhibitory failures). Response activation was evaluated as time to respond to go targets (reaction time). We hypothesized the percentage of inhibitory failures to no-go targets would be greater when followed by food images than neutral images. METHODS: Thirty (30) participants (14 female) aged 32.9 years with a BMI of 32.7 (mean + SD) completed a food specific Go/NoGo task. Participants were required to respond to energy dense food images or neutral (non-food) images. After the cue image was presented, it turned either solid green (go) or blue (no-go). Participants were instructed to respond by pressing a button when the green target appeared and to withhold their response when the blue target appeared. Failing to withhold responding when the blue target appeared after a food-related image is indicative of poor motor impulsivity for food cues. Reaction time to go cues was also recorded. RESULTS: The proportion of inhibitory failures to no-go targets following food cues (10.8%) was significantly greater than the proportion of inhibitory failures to no-go targets following neutral cues (1.9%), P < 0.001). In measuring response activation, no differences were observed in reaction time towards go cues between food and neutral cues: Food 250.58 ± 82.62, Neutral 260.54 ± 112.97. CONCLUSIONS: Adults classified as overweight to obese were less able to inhibit responding to a No-Go cue followed by a food-related image compared to neutral images. Reaction time was not different when responding to food or neutral cues, indicating the effect observed was not caused by a decrease in reaction time (i.e., accuracy was not traded for speed). Our findings suggest that food-related cues promote disinhibition and could be a prime driver of over consumption and obesity. FUNDING SOURCES: The present study was supported by the National Institutes of Health P30GM127211 of the National Institute of General Medical Sciences.