Investigating self-representation with virtual reality
Ke Ma · Leiden Repository (Leiden University) · 2016
The main issue addressed in this thesis is the degree to which the representation of our body is flexible, and what possible implication this has. By using the virtual hand illusion (VHI) paradigm, we provided evidence for a dissociation between subjective ownership perception and the skin conductance response (SCR). We then investigated perceived ownership for a virtual balloon and a virtual square, and found that noncorporeal objects can be incorporated as a body part under certain conditions. We also analyzed the contribution of the visual form of the effector and sense of agency for senses of ownership. We proposed that the sense of ownership arises from a rather broad integration of both top-down and bottom-up factors, without a modulation relationship between them, and it is possible that information from one source can compensate for a lack of information from another. We further found that self-representation can be affected by context-induced spatial reference frames. Finally, we replicated the enfacement illusion (EI) in a virtual environment and also showed that participants can incorporate some facial features of the viewed face when multisensory stimulation was applied. Overall, the present thesis provides strong evidence that body representations are flexible in many ways.