Attentional bias to unhealthy food in individuals with severe obesity and binge eating

Abstract

Attentional bias is an implicit cognition relevant to development and maintenance of obesity, but little is known of how binge eating modulates attentional bias in severe obesity. This study investigated attentional bias towards unhealthy foods at different stages of attentional processing in a clinical sample, comparing obese patients (Body Mass Index, BMI>35 kg/m2) with and without binge eating behaviors. Participants were separated into two groups according to their score on the Binge Eating Scale (BES): no binge eating (NB; score ≤17; n = 23) and binge eating (BE; score > 17; n = 19). Participants performed a computerized visual probe task designed to evaluate attentional bias in different stages of attentional process; matching pairs of unhealthy food and matching non-food pictures concealed a target for 100, 500 or 2000 ms. Reduced reaction times to targets following food-related images are indicative of attentional bias towards food images. BE group exhibited a greater bias towards food than NB. Both groups showed positive attentional bias to food in the initial orientation stage (100 ms), whereas bias was close to zero in the maintenance of attention stage (2000 ms), suggesting ambivalent approach-avoidance responses to food stimuli. Only the BE group showed a bias towards food images when displayed for 500 ms, indicating disengaging from food-related stimuli was faster in NB group. Although both groups were ambivalent about attending to food cues, slower attentional disengagement from unhealthy food might be a cognitive marker of binge eating behavior in severe obesity.