A cardio-visual full body illusion improves body size estimation in healthy women

Einleitung Body image distortion (BID), i.e., the misestimation of one's own body size, is found in healthy women, and presents a risk factor for the development of eating disorders. According to the allocentric lock hypothesis, BID is the result of experiencing the body from an allocentric perspective, compared to egocentric perspective. BID has been linked to interoceptive deficits and can be improved by visuotactile body illusions.

Methoden We investigated the effects of a cardio-visual full body illusion (cvFBI) on BID in 45 healthy women. The cvFBI was induced by presenting a 3D body scan of the participant in VR, flashing with a short (230ms) or long (530ms) delay after the R-peak of the participant's ECG, or not flashing at all. The same conditions (short delay, long delay, no flash) combined with a 3D object (cube) served as control conditions. Before and after each illusion condition participants performed an egocentric body size estimation task (width and circumference estimations of different body parts), and an allocentric body size estimation task in VR (adjusting the distorted 3D body to the perceived body size).

Ergebnisse The results show a significant change in egocentric body size estimations, irrespective of cardio-visual feedback or VR content. No change in size estimations could be found in the allocentric body size estimations.

Schlussfolgerung These results demonstrate that egocentric body representations are malleable, while allocentric body representations are stable, lending support to the allocentric lock hypothesis. This study offers new implications for interventions to target BID in healthy women and women with eating disorders.

Publication History

Article published online:
06 September 2023