Abstract
Stereopsis plays an important role in everyday visuomotor tasks. However, abnormal visual experience during development caused by amblyopia and/or strabismus may result in reduced or absent stereopsis. While perceptual learning (PL) can improve stereopsis in adults with abnormal binocular vision, it requires many trials (Ding & Levi, 2011). Thus, attention and compliance may limit the utility of PL. Game principles can be used to tackle both challenges. Indeed, several studies have reported the benefits of using video games to treat amblyopia. Recently, the introduction of consumer Virtual Reality (VR) devices has opened the opportunity to design new PL therapies. Our aim was to test whether VR can be used to train stereo-anomalous observers to rely on disparity cues. We designed two games to train stereovision using a VR headset. One game required players to launch a dart when a dartboard moving in depth, is in the same depth plane as the dart. The other game required the player to destroy the nearest of several ghosts. Importantly, initially the games provided multiple cues for judging depth (shadows, perspective, motion parallax, and disparity). As players progressed we selectively removed cues (shadows, perspective and motion parallax), finally leaving only disparity cues. Play started with a dichoptic calibration, where strabismic angles were corrected and the input to the two eyes was perceptually balanced by reducing the luminance/contrast to the dominant eye, creating a single image and reducing suppression. High contrast binocular frames were used to facilitate binocular fusion. Our preliminary results show that most of the stereo deficient players improved in the game, and several showed transfer to both clinical (Randot®) and dynamic Random Dot Stereoacuity tests (Ding & Levi, 2011). We conclude that consumer VR devices may provide a new tool for the recovery of stereopsis in adults with abnormal binocular vision.
Meeting abstract presented at VSS 2017