Virtual Reality Lab - Universitat de Barcelona

The present study has as main objective to determine the factors that predict a change in the overestimation of the body image by the use of the illusion of property of an avatar in virtual reality. The experiment consists of exposing a non-clinical sample of 50 subjects to a progressive increase in the body mass of their virtual avatar while receiving visuotactil estimulation.

Body overestimation is measured by the Body Image Assessment Scale (BIAS-BD) and other factors except gender, age, and BMI are obtained from: the Drive for Thinness (EDI DT) and Body Dissatisfaction (EDI-BD) scales from the Eating Disorders Inventory (EDI-2), the weight subscale of the Physical Appearance State and Trait Anxiety Scale (PASTASW), Likert scales from 0 to 100 for the evaluation of the illusion of property, anxiety in relation to one's own body and fear of gaining weight and the Embodiment Questionnaire (EQ).

The most relevant factors that have shown a significant proportional correlation with the final body overestimation are: PASTAS-State and –Trait items related to thighs and the total scores, of PASTAS-Trait the item related to the overweight and the BIAS-BD body overestimation and body dissatisfaction. The factor that has shown a significant effect on the change in body over estimation is the body anxiety experienced in the first phase of immersion in the avatar (of body size equal to that of the subject). The variables that have been included in the prediction model are: body over estimation obtained by BIAS-BD and the item related to overweight of PASTAS-Trait, both variables obtained at baseline, i.e. pre-intervention; in addition to the variable body anxiety experienced in the first phase of immersion in the avatar. The results of this study demonstrate that it is possible to establish a model capable of predicting changes induced by virtual reality in body distortion, however a further research with a larger sample is needed, as well as a greater number of variables to establish a practical model.