Feeling disgust towards one's own body: A psychophysiological investigation using immersive virtual reality

Feeling disgust towards one’s own body is a maladaptive emotion referred to as body-related self-disgust (BRSD). BRSD is associated with the onset, maintenance, and relapses of eating disorders (EDs). This study aimed to characterise BRSD at psychophysiological level in females with different BMI. Forty normoweight (NW) and forty overweight (OW) females completed two counterbalanced virtual reality sessions. In one session, BRSD was elicited through embodiment of avatars with different BMI (underweight, normoweight, obese); in the control session, participants observed disgusting (and neutral) video-clips. Self-report measures of BRSD and visceral sensations, together with cardiac (electrocardiography) and gastric (electrogastrography) measures were collected within conditions. Compared to NW, the OW group reported higher levels of body dissatisfaction, body image concerns, and ED risk. The embodiment paradigm successfully elicited BRSD, as both groups reported greater BRSD when embodying the obese avatar. Notably, the OW group also experienced increased BRSD during embodiment of the underweight avatar. Gastric physiology revealed that while NW participants showed faster dominant frequency during embodiment of underweight avatar and, at trend level, obese avatar compared to the normoweight one, this pattern was not observed in OW individuals. Additional analyses indicate that, in both groups, BRSD was associated with perceived gastric (but not cardiac) sensations and avatar type. These findings indicate that embodiment of extreme BMI avatars elicits BRSD and distinct gastric responses, differentiating NW and OW individuals at subjective and physiological levels. They further identify the gastric domain as a key correlate of BRSD, suggesting novel targets for clinical interventions.