The Impact of Avatar Appearance, Perspective and Context on Gait Variability and User Experience in Virtual Reality
Markus Wirth, Stefan Gradl, Georg Prosinger, Felix Kluge, Daniel Roth, Bjoern M. Eskofier
Abstract
Gait supervision plays an important role in the diagnosis, analysis and rehabilitation of motor impairments and neurodegenerative disorders. For example, in Parkinson's disease, gait assessment is used for progression observation and medication guidance. Previous work has presented the potential of virtual reality (VR) supported gait applications. While virtual environments and user representation strategies are used for gait applications, the influence of appearance and context cues on gait performance is not extensively researched. In this paper, we analyzed the influence of avatar appearance, environment awareness, and camera perspective on gait parameters relevant for clinical application. Four different avatar appearances, varying in abstraction, two environmental settings, as well as an egocentric and exocentric camera perspective were compared in three walking tasks on a treadmill. Our results show that variability, as an indicator for gait stability, is significantly impacted by VR exposure in comparison to a real world (in vivo) baseline. Further, our results revealed that walking tasks influence gait behavior significantly different in VR compared to in vivo. Overall, these findings suggest that particular care has to be taken when assessing gait characteristics acquired from subjects immersed in VR and that equivalence of results with in vivo may not be blindly assumed.