Sarvani Dharwada, Maria Gallagher
Despite significant advancements in Virtual Reality (VR) technology, exposure to VR can induce side effects on the user. One such effect is Depersonalisation and Derealisation (DPDR): feelings of detachment from the self and surroundings. The exact mechanism behind the development of DPDR symptoms following VR use is unknown. Stable representations of the bodily self depend on the integration of visual and vestibular signals. However, VR disrupts this integration. The brain is thought to resolve visuo-vestibular conflict by downweighting vestibular signals. However, whether this reweighting accounts for VR-induced DPDR has not been tested. We investigated whether changes in vestibular sensitivity are associated with DPDR. Thirty-two participants were exposed to 10 min of either roll optic flow, inducing visuo-vestibular conflict, or random dot motion, inducing no conflict. Vestibular sensitivity was assessed before and after VR using a psychophysical detection task. A moderation analysis revealed that in the roll condition, participants whose sensitivity to GVS increased following VR reported the greatest increases in DPDR, whereas no such relationship was seen in the random condition. Thus, these findings suggest that individuals who are unable to resolve the sensory conflict by vestibular-downweighting are most susceptible to DPDR.