Need a hand?: how appearance affects the virtual hand illusion.

How does the appearance of a virtual hand affect own-body perception? Previous studies have compared either two or three hand models at a time, with their appearances limited to realistic hands and abstract or simple objects. To investigate the effects of different realisms, render styles, and sensitivities to pain on the virtual hand illusion (VHI), we conduct two studies in which participants take on controllable hand models with six distinct appearances. We collect questionnaire data and comments regarding responses to impacts and threats to assess differences in the strength of the VHI. Our findings indicate that an illusion can be created for any model for some participants, but that the effect is perceived weakest for a non-anthropomorphic block model and strongest for a realistic human hand model in direct comparison. We furthermore find that the responses to our experiments highly vary between participants.