Poster Session: Extended Reality-based Minifying Lens Effects Decreases Dynamic Visual Acuity

Abstract

Dynamic visual acuity (DVA) refers to the ability to visualize objects in motion. Gravitational (G)-transitions can occur during spaceflight inducing rapid sensorimotor adaptation, impaired DVA, and gaze control as observed in astronauts upon their return to Earth {1}. Previous research has used 0.5x lenses to simulate the decreased DVA experienced by a returning astronaut {2}. Minifying lenses cause visual inputs to move less than normal, which creates visual-vestibular conflict and can impair DVA. Our study reports the novel development and use of head-mounted, extended reality to simulate decreased DVA from G-transitions. We developed and tested this minifying lens effect with 5 healthy subjects (best correctable visual acuity of 20/20). The level of minimization was decreased in a stepwise manner from: normal, 30% smaller, 50% smaller, 70% smaller, 80% smaller. Measured DVAs were 0.485; 0.525; 0.695; 0.655; 0.855 LogMAR respectively, showing a decreased DVA as the level of minimization increased. There are currently no DVA assessment techniques in microgravity, which is why DVA and vestibular adaptations in space are poorly understood. Our group aims to address this crucial knowledge gap by developing a head-mounted visual assessment system that can measure DVA and highlight the potential of using extended reality-based minifying lenses to study vestibular dysfunction in both space and terrestrial settings {3}.

Footnotes

 Funding: Funding: NASA Grant [80NSSC20K183]: A Non-intrusive Ocular Monitoring Framework to Model Ocular Structure and Functional Changes due to Long-term Spaceflight.