Virtual Reality Based Assessment of Static Object Visual Search in Ocular Compared to Cerebral Visual Impairment

摘要

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, such as eye and hand tracking, affords a high degree of experimental control, task flexibility, participant engagement, and enhanced data capture. Individuals with visual impairment typically have difficulties identifying objects in a cluttered environment. Furthermore, these difficulties may differ depending on the type of visual impairment. Specifically, individuals with cortical/cerebral visual impairment (CVI) may show a greater sensitivity to visual task complexity compared to those with ocular based visual impairment (OVI). We have developed a VR environment with integrated eye and hand tracking to simulate exploring a toy box to assess performance on a static object-based visual search task. A grid of toys was displayed for a brief duration while participants found and fixated on a specific toy hidden among others. For a given trial, we manipulated multiple factors: the number of unique distractor toys, a color/theme matched toy, and the background clutter. 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 greatly 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 theoretical foundation for the creation of new assessment and training paradigms for visually impaired individuals.