Evaluating the Sense of Embodiment through Out-of-Body Experience and Tactile Feedback

Abstract

Out-of-body experience (OBE) is generated by sensory disintegration. In virtual reality (VR), we can provide OBE to people by switching the first-person perspective (1PP) to the third-person perspective (3PP). Generally, 1PP is the choice for high body ownership and presence. Moreover, tactile feedback that is experienced from the 1PP can provide a higher immersive experience. However, whether the combination of 3PP and tactile feedback could affect the sense of embodiment in immersive environments is underexplored. Thus, we conducted a 2 × 2 (OBE: 1PP vs. 3PP × Tactile Feedback [TF]: with vs. without tactile feedback) VR study to discover the effect of OBE in the presence of TF. In our study, we examined OBE and TF through the five dimensions of the sense of embodiment: body ownership, agency, tactile sensations, location of the body, and response to external stimuli. We developed an application to replicate the rubber hand illusion (RHI) study with partial body tracking. We found significant results for both OBE and TF in different dimensions of embodiment. Specifically, we revealed that 3PP decreased the body's sense of body ownership, agency, and location. Moreover, enabling tactile feedback induced tactile sensations and responses to external stimuli. In the remainder of this paper, we discuss our findings and limitations and provide directions for future studies on OBE in VR.