The present study focused on the impact of immersive virtual reality (VR) technology on the coordination dynamics of walking, because of VR-induced symptoms and effects (e.g., motion sickness, postural instability, and disorientation) reported in the literature. Subjects were instructed to walk on a treadmill in a virtual and a real environment, while walking speeds were systematically varied. The virtual laboratory environment closely resembled the real laboratory environment. A third experimental condition was included controlling for the restricted view of a head mounted display (HMD) of the VR system. Movement of arms and legs were recorded with an Optotrak system. The main finding was that, for all speed conditions, there was an increased stride frequency in the VR environment compared to the other conditions. At the lower walking speeds, this coincided with a stronger locking of the arm movements on the stride frequency, and an increased mean relative phase between left arm and right arm movements as well as between ipsilateral arm and leg movements. No significant differences in the stability of the walking patterns were observed. Most importantly though, the impact of VR immersion was not large, was primarily limited to the lower walking velocity range, and could be further reduced by correcting for the effects of increased stride frequency by applying dimensionless analysis. The restricted view of the HMD did not significantly influence walking coordination. On the basis of these findings, it is concluded that immersive VR is a suitable tool to investigate perception-action coupling during walking, allowing for a systematic manipulation of optic flow parameters.
ASJC Scopus subject areas
- Control and Systems Engineering
- Human-Computer Interaction
- Computer Vision and Pattern Recognition