Delusionized? Potential Harms of Proprioceptive Manipulations through Hand Redirection in Virtual Reality

To enhance interactions in VR, hand redirection (HR)-based illusion techniques apply offsets between the virtual and real-world position of users’ hands. While adaptation to such HR offsets is recognized, their impact on proprioception accuracy remains unexplored. However, deploying HR without understanding its potential effects on proprioception accuracy may pose risks to users in real-life situations. To investigate this, we conducted an experiment with 22 participants, studying the influence of prolonged exposure to unnoticeable HR offsets on proprioceptive accuracy during hand-reaching in VR. Our results show that proprioceptive accuracy declines significantly after prolonged exposure to redirected hand interactions. However, short-time exposure to unaltered hand interactions can – yet only partially – restore normal levels. Thus, we advocate being aware of potential risks arising from prolonged exposure to visual-proprioceptive offsets to ensure users’ safety.