Eye-tracking study on the effects of happiness and sadness on body dissatisfaction and selective visual attention during mirror exposure in bulimia nervosa.

Abstract

Abundant research points to the central role of body image disturbances in the occurrence of eating disorders (ED). While emotional arousal has been identified as a trigger for binge eating in bulimia nervosa (BN), empirical knowledge on the influence of emotions on body image in individuals with BN is scarce. The present study sought to experimentally examine effects of a positive and negative emotion induction on body dissatisfaction and selective attention towards negatively valenced body parts among people with BN. In a randomized-controlled cross-over design, happiness and sadness were induced by film clips one-week apart in women with BN (n = 23) and non-ED controls (n = 26). After the emotion induction, participants looked at their body in a full-length mirror, while their attentional allocation was recorded with the help of a mobile eye tracker. Participants repeatedly rated their momentary body dissatisfaction. Induction of happiness led to a significant decrease in self-reported body dissatisfaction. Furthermore, attentional bias (higher gaze duration and frequency) towards the most disliked body part relative to the most liked body part was significantly greater in the sadness than happiness condition in BN. No significant effects of emotion induction on gaze duration and gaze frequency during mirror exposure were found for controls. In line with assumptions of current models on ED, findings support the notion that emotional state influences the body image of patients with BN.