Systematic Review and Meta-Analysis of Virtual Reality in Mental Healthcare: Effects of Full Body Illusions on Body Image Disturbance

Abstract

Background: Body image (BI) disturbances have been identified in both clinical and non-clinical populations. Virtual reality (VR) has recently been used as a tool for modulating BI disturbances through the use of eliciting a full body illusion (FBI). This meta-analysis is the first to collate evidence on the effectiveness of an FBI to reduce BI disturbances in both clinical and non-clinical populations.Methods: We performed a literature search in MEDLINE (PubMed), EMBASE, PsychINFO, and Web of Science with the keywords and synonyms for “virtual reality” and “body image” to identify published studies until September 2020. We included studies that (1) created an FBI with a modified body shape or size and (2) reported BI disturbance outcomes both before and directly after the FBI. FBI was defined as a head-mounted display (HMD)-based simulation of embodying a virtual body from an egocentric perspective in an immersive 3D computer-generated environment.Results: Of the 398 identified unique studies, 13 were included after reading full-texts. Four of these studies were eligible for a meta-analysis on BI distortion inducing a small virtual body FBI in healthy females. Significant post-intervention results were found for estimations of shoulder width, hip width, and abdomen width, with the largest reductions in size being the estimation of shoulder circumference (SMD = −1.3; 95% CI: −2.2 to −0.4; p = 0.004) and hip circumference (SMD = −1.0; 95% CI: −1.6 to −0.4; p = 0.004). Mixed results were found in non-aggregated studies from large virtual body FBIs in terms of both estimated body size and BI dissatisfaction and in small virtual body FBI in terms of BI dissatisfaction.Conclusions: The findings presented in this paper suggest that the participants' BIs were able to conform to both an increased as well as a reduced virtual body size. However, because of the paucity of research in this field, the extent of the clinical utility of FBIs still remains unclear. In light of these limitations, we provide implications for future research about the clinical utility of FBIs for modulating BI-related outcomes.

Resize Me! Exploring the User Experience of Embodied Realistic Modulatable Avatars for Body Image Intervention in Virtual Reality

“…Treatments for body image disturbances mainly rely on cognitive-behavioral therapy, typically combining psychoeducation and self-monitoring tasks, mirror exposure, or video feedback (Farrell et al, 2006;Ziser et al, 2018;Griffen et al, 2018). Based on the fundamentals of these established methods, an increasing number of researchers have started to explore VR applications as additional support for attitude and behavior change in general (Wienrich et al, 2021) and therapy of body image disturbance (Riva, 1997;Ferrer-Garcia et al, 2009Riva et al, 2019;Turbyne et al, 2021) and obesity in particular (Horne et al, 2020;Döllinger et al, 2019).…”

“…In addition to practicing beneficial diet and exercise habits, the focus lies on examining one's own body and managing disturbances in body image. Disturbances in body image, as part of a variety of body weight-and eating disorders (Rosen, 2001;Thompson and Tantleff-Dunn, 1998), are composed of a misperception of body dimensions (body image distortion) and the inability to like, accept, or value one's own body (body image dissatisfaction) (Turbyne et al, 2021). The treatment methods are various, including a confrontation with one's own body using a mirror reflection or video recordings, as well as self-acceptance exercises such as meditation (Ziser et al, 2018;Stewart, 2004).…”

“…In recent years, novel methods complementing the therapy of body image disturbances based on virtual reality (VR) have been explored (Ferrer-Garcia et al, 2013;Wiederhold et al, 2016;Riva et al, 2019). These methods often use 3D models of human beings (Horne et al, 2020;Turbyne et al, 2021), which can be called avatar as they represent a particular user (Bailenson and Blascovich, 2004). VR in general, and the confrontation with avatars in particular, have great potential to influence human perception and behavior (Wienrich et al, 2021).…”

“…It increases the emotional response to important virtual stimuli (Gall et al, 2021), and users tend to adapt their behavior and attitudes to the characteristics of their embodied avatar (Ratan et al, 2020;Yee and Bailenson, 2007). In the context of body image, avatars have been utilized to expose users of a VR system to virtual bodies or body parts varying in size and/or shape to investigate the principles of body weight perception (Thaler, 2019;Wolf et al, 2020Wolf et al, , 2021Wolf et al, , 2022 or to influence the perception or attitude towards the user's own body (Turbyne et al, 2021). Döllinger et al (2019) suggested simulating body weight changes using modulatable, photorealistic, personalized, and embodied avatars, and Turbyne et al (2021) further stated that the users' body image may conform to these avatars after being embodied to it.…”

“…In the context of body image, avatars have been utilized to expose users of a VR system to virtual bodies or body parts varying in size and/or shape to investigate the principles of body weight perception (Thaler, 2019;Wolf et al, 2020Wolf et al, , 2021Wolf et al, , 2022 or to influence the perception or attitude towards the user's own body (Turbyne et al, 2021). Döllinger et al (2019) suggested simulating body weight changes using modulatable, photorealistic, personalized, and embodied avatars, and Turbyne et al (2021) further stated that the users' body image may conform to these avatars after being embodied to it. Recent developments in computer graphics allow the generation of photorealistic avatars that exactly match a person's real-life appearance within a short duration and at low-cost (Achenbach et al, 2017;Wenninger et al, 2020;Bartl et al, 2021).…”