Search Results (6)

The full-body illusion (FBI) is a phenomenon where individuals experience body perception not in their physical body but in an external virtual body. Previous studies have shown that the relationship between the self and the virtual body influences the occurrence and intensity of the FBI. However, the influence of interpersonal factors on the FBI has not been explored. This study investigated the effect of interpersonal synchrony on body perception through an evaluation experiment involving the FBI. Specifically, the participant and an experimenter clapped together while their movements were recorded by a video camera placed behind the participant and displayed to them via a head-mounted display (HMD). This setup presented synchronous visuotactile stimuli, aligning the visual feedback with the tactile sensations in the participant’s hands, to induce the FBI. The experimenter’s clapping rhythm was manipulated to either be synchronous or asynchronous with the participant’s rhythm, thus controlling the state of movement synchronization between the participant and the experimenter. The impact on the participant’s body perception was then assessed through subjective reports. The results indicated that when the clapping rhythm was synchronized with the other person, there was a significant reduction in touch referral to the participant’s virtual body. Additionally, there was a trend toward a reduction in ownership. This study demonstrated for the first time that interpersonal synchrony affects body perception. Full article

Background/Objectives: A high number of patients who suffer the amputation of a lower limb will present psychological problems such as anxiety, depression, and post-traumatic stress disorder after surgery. This study embodies participants in a self-avatar with a right lower-limb amputation in a virtual reality environment. The aim was to determine if this experience increases anxiety levels compared to embodiment in a normal avatar. The study also examines whether body appreciation is related to anxiety levels. Methods: Subjects completed the Body Appreciation Scale (BAS) questionnaire before being immersed in the virtual environment, the Visual Analogue Scale for Anxiety (VAS-A) after each condition, and the Embodiment Questionnaire at the end of the experiment. Results: Univariate analysis showed that participants reported significantly higher levels of anxiety when exposed to the virtual avatar with an amputation compared to the full virtual body avatar. These results indicate that lower levels of body appreciation were associated with higher levels of anxiety across conditions, suggesting that participants with lower body appreciation experienced greater psychological maladjustment (measured by anxiety) in response to the virtual scenarios. Conclusions: The results suggest that the virtual avatar with a lower-limb amputation elicited significantly greater anxiety, and that body appreciation plays a key role in moderating this psychological response. Future research could focus on developing virtual exposure-based therapy for amputees using virtual reality to help reduce the anxiety experienced by patients during this process. Full article

The embodied self is rooted in the self-body in the “here and now”. The senses of self-ownership and self-agency have been proposed as the basis of the sense of embodied self, and many experimental studies have been conducted on this subject. This review summarizes the experimental research on the embodied self that has been conducted over the past 20 years, mainly from the perspective of multisensory integration and sensorimotor integration regarding the self-body. Furthermore, the phenomenon of back projection, in which changes in an external object (e.g., a rubber hand) with which one has a sense of ownership have an inverse influence on the sensation and movement of one’s own body, is discussed. This postulates that the self-body illusion is not merely an illusion caused by multisensory and/or sensorimotor integration, but is the incorporation of an external object into the self-body representation in the brain. As an extension of this fact, we will also review research on the mirror neuron system, which is considered to be the neural basis of recognition of others, and discuss how the neural basis of self-body recognition and the mirror neuron system can be regarded as essentially the same. Full article

Fear of gaining weight (FGW), body image disturbances, associated anxiety and body-related attentional bias are the core symptoms of anorexia nervosa (AN) and play critical roles in its development and maintenance. The aim of the current study is to evaluate the usefulness of virtual reality-based body exposure software for the assessment of important body-related cognitive and emotional responses in AN. Thirty female patients with AN, one of them subclinical, and 43 healthy college women, 25 with low body dissatisfaction (BD) and 18 with high BD, owned a virtual body that had their silhouette and body mass index. Full-body illusion (FBI) over the virtual body was induced using both visuo-motor and visuo-tactile stimulation. Once the FBI was induced, the FBI itself, FGW, body anxiety and body-related attentional bias toward weight-related and non-weight-related body areas were assessed. One-way analyses of covariance (ANCOVA), controlling for age, showed that AN patients reported higher FGW, body anxiety and body-related attentional bias than healthy controls. Unexpectedly, patients with AN reported significantly lower FBI levels than healthy participants. Finally, Pearson correlations showed significant relationships between visual analog scales and body-related attentional bias measures, compared to other eating disorder measures. These results provide evidence about the usefulness of virtual reality-based body exposure to elicit FGW and other body-related disturbances in AN patients. Thus, it may be a suitable intervention for reducing these emotional responses and for easing weight recovery. Full article

Background. The effective illusory ownership over an artificial body in modulating body representations in healthy and eating disorders population has been repeatedly reported in recent literature. In this study, we extended this research in the field of obesity: specifically, we investigated whether ownership over a virtual body with a skinny abdomen might be successfully experienced by participants affected by obesity. Methods. Fifteen participants with obesity and fifteen healthy-weight participants took part at this study in which the VR-Full-Body Illusion was adopted. The strength of illusion was investigated through the traditional Embodiment Questionnaire, while changes in bodily experience were measured through a body size estimation task. Results. Participants with obesity as well as healthy-weight participants reported to experience the illusion. About the body size estimation task, both groups reported changes only in the estimation of the abdomen’s circumference after the experimental condition, in absence of any another difference. Discussion. Participants with obesity reported to experience the illusion over a skinny avatar, but the modulation of the bodily experience seems controversial. Future lines of research exploiting this technique for modulating body representations in obesity, specifically in terms of potential therapeutic use, were discussed. Full article

Body image disturbances (BIDs) have been widely studied using virtual reality (VR) devices that induce a full body illusion (FBI) and allow manipulation of the individual’s perceptual and affective experiences of the body. This study aimed to assess whether the induction of the FBI over a virtual body would produce changes in body-related anxiety and BIDs using a new whole-body visuo-tactile stimulation procedure. Fifty non-clinical participants were randomly assigned to synchronous or asynchronous visuo-tactile groups. During the pre-assessment, all participants filled in BIDs and body-anxiety questionnaires. Then, they were embodied into two virtual bodies (VBs): firstly, with their real measurements, and secondly, with a larger-size body. Body image disturbances, body anxiety, fear of gaining weight, and FBI levels were assessed after exposure to each avatar. All participants in both conditions showed higher levels of BIDs and body anxiety after owning the larger-size VB than after owning the real-size VB (p < 0.05). The synchronous visuo-tactile group had higher scores, although the differences did not reach statistical significance. This study provides evidence of the usefulness of this new embodiment-based technique to induce changes in BIDs or body anxiety in a non-clinical sample, being suitable for use in future body image interventions. Full article