Abstract
When interacting with virtual environments, feedback delays between making a hand movement and seeing the visual consequences of that movement are detrimental for our senses of body-ownership, agency and presence. However, to date it is unknown whether prolonged exposure to the delay, and thus the possibility to adapt to it, leads to the recovery of these senses. Here we investigated the immediate effects of an added feedback delay of 200 ms on ownership, agency and presence, as well as the effects of prolonged exposure to the delay. Participants performed a predictable target-tracking task (see Rohde, van Dam & Ernst, Journal of Vision, 2014) in a virtual reality environment. We measured the participants' performance in terms of behavioural lag and spatial errors with respect to the target in both no-delay and added-delay conditions. Additionally, participants rated their sense of ownership, agency and presence on each trial using sliding scales. These single trial ratings were compared to the results of the more traditional questionnaires for ownership and agency (Kalckert & Ehrsson, Frontiers in Human Neuroscience, 2012) and presence (Schubert, Friedmann & Regenbrecht, Presence: Teleoperators and Virtual Environments, 2001) for both no-delay and added-delay conditions. We found that the participants' single trial ratings corresponded very well to the results of the traditional questionnaire measures for both the no-delay and added-delay conditions. Moreover, not only did participants behaviorally adapt to the delay over time, their senses of ownership and agency significantly improved with prolonged exposure to the delay as well. The sense of presence showed a smaller detriment as a result of the added delay and therefor a smaller trend towards prolonged exposure being effective. Together the results suggest that there is a tight link between the ability to perform a behavioral task and the sense of ownership and agency in virtual reality.
Meeting abstract presented at VSS 2018