Résumé
Internalized body size stigma contributes to negative body image and can distort how individuals perceive their own body. Virtual reality (VR) offers a potentially novel platform for interventions that alter body representation when the user embodies a virtual body (i.e., an avatar) that is different from their own body. However, the influence of pre-existing body image attitudes on the virtual embodiment process remains unclear. In the present study, we used a body-scaled affordance paradigm to examine how embodying avatars with altered body size (20% smaller, equal, or 20% larger; N = 20 per condition) affects body perception in VR and how this effect is modulated by body image constructs. Participants completed affordance tasks in physical and virtual environments in which they were presented with an aperture (space between two poles) of varying widths. Participants were asked to determine the minimal apertures they could pass through in both action (walk sideways through adjustable apertures) and perception (visually estimating aperture width) tasks. Affordance ratios were calculated as the ratio of thresholds from the perception and action tasks. These ratios were adjusted for VR-specific distortions and used as indicators of perceived body size relative to one’s action capabilities (i.e., the physical/avatar body size). Regression analyses revealed that higher internalized body size bias and body-related guilt were associated with persistent overestimation of body size in VR. These findings highlight that negative body image attitudes and emotions, particularly those linked to body size stigma, may hinder perceptual adaptation to altered body representations in VR.
