Title: HCC: Small: Determining the Effects of Latency in Virtual Reality Physical Rehabilitation

Funding Source: National Science Foundation (Award# IIS-1218283)

Funding Amount: $472,840

Duration: 2012-2015

Personnel:

PI: John Quarles, Ph.D.

Research Assistant: Rongkai Guo

Research Assistant: Gayani Samaraweera

Abstract:

The effect of latency (i.e., how quickly a system can respond to user input) on users has been one of the fundamental research areas in virtual reality (VR) for many years, but its effect on persons with physical disabilities is still unknown, even though it could have a significant an impact on VR-based physical rehabilitation.

The objective of this research is to understand how latency of visual feedback in VR can impact interaction performance, perception, and subjective experience for users with reaction time and reflex deficits (e.g., due to neurological, vestibular, balance issues) and investigate how this ultimately impacts the effectiveness of VR rehabilitation. Based on preliminary data, the central hypothesis is: latency will be less perceivable but will have will have a more significant impact on interaction performance for persons with disabilities as compared to healthy persons. To test this hypothesis, the Dr. Quarles will address the main set of applications in VR rehabilitation: games, exercise, and accessibility. Specifically, Dr. Quarles aims to 1) determine the effects of latency in VR rehabilitation games for persons with disabilities, 2) determine the effects of latency on the effectiveness of visual feedback during rehabilitation exercises in virtual environments (VE) for persons with disabilities and 3) determine the effects of latency on accessibility in a VE for persons with disabilities. Through a series of empirical studies, Dr. Quarles expects to provide an understanding of how latency in VR affects persons with disabilities determining their latency thresholds in VR, specifically with respect to interaction performance, physiological response, perception, and subjective impressions. This research is significant because it has potentially negative implications for the effectiveness of VR rehabilitation and more generally it is a critical step towards the grand challenge of universal usability in VR. This work will offer a deeper understanding of the effectiveness of VR as a medium for rehabilitation.