Assessing Visual Search Performance in Ocular Compared to Cerebral Visual Impairment Using a Virtual Reality Simulation of Human Dynamic Movement

Virtual reality (VR) can provide robust assessment of cognitive spatial processing skills in individuals with visual impairment. VR combined with objective measures of behavioral performance (i.e., eye tracking) affords a high degree of experimental control, task flexibility, participant engagement, and enhanced data capture. Individuals with visual impairment typically have difficulties identifying people in crowded environments; these difficulties may differ depending on the origin of the visual impairment. Specifically, individuals with cortical/cerebral visual impairment (CVI) may show a greater sensitivity to scenarios of high dynamic visual complexity compared to those with ocular based visual impairment (OVI). To test potential differences in visual search performance, we have developed a first-person perspective VR environment integrated with eye tracking designed to simulate the dynamic movement of humans in a hallway. Participants were tasked with locating a specific target individual walking among a crowd of people moving in various directions in the hallway. To assess the effect of task difficulty, we manipulated factors of crowd density and presence of object clutter within the hallway. Results to date show that both visually impaired groups demonstrate increased variability in search patterns and reaction times as compared to controls. Additionally, performance of the CVI group fluctuates greater as a function of task difficulty. Findings from the current work demonstrate a successful interaction between individuals with visual impairments and VR simulations in assessing high level visual function. Further studies will serve as a theoretical foundation for the creation of new assessment and training paradigms for visually impaired individuals.