Recovery of Stereopsis in Age-Related Macular Degeneration

描述（申请人提供）：老年性黄斑变性影响中央视力，损害高灵敏度视觉功能。患有AMD的人抱怨在日常工作中有困难，比如阅读、识别面孔和看电视。最近的研究报告显示，他们有手眼协调和抓握困难，这与大多数AMD患者缺乏深度知觉的数据一致。当两只眼睛有非常不同的视力丧失模式时，特别是当较强的一只眼睛决定双眼注视方向时，而不考虑另一只眼睛相应注视位置的功能状态时，立体视觉可能受损。深度知觉的丧失不仅会影响需要手眼协调的任务，而且会对移动和避障造成严重后果。在这一建议中，我们研究了通过鼓励个体使用具有相似功能的两只眼睛的固定位点来恢复AMD个体立体视觉的潜力。我们首先在Aim 1中检查深度感知的潜力。这需要映射两只眼睛的残余功能区域，以确定在外围是否有相应的点可以支持深度感知。在目标2中，我们确定观察者是否能够结合来自两只眼睛的信息（立体视觉的必要先决条件），以及他们是否具有任何程度的深度感知。在Aim 3中，我们检验了AMD患者能够使用不同固定位点的假设

DESCRIPTION (provided by applicant): Age-related macular degeneration affects central vision and impairs high acuity visual function. Individuals with AMD complain about difficulty with everyday tasks such as reading, recognizing faces and watching television. More recent studies report difficulty with eye-hand coordination and grasping, consistent with data showing that the majority of individuals with AMD have little depth perception. Stereopsis can be impaired when the two eyes have very disparate patterns of vision loss, particularly when the stronger eye determines binocular gaze direction, without regard to the functional status of the corresponding fixation location in the other eye. Loss of depth perception not only impacts tasks requiring eye hand coordination, but it can have serious consequences for mobility and obstacle avoidance. In this proposal we examine the potential to restore stereopsis in individuals with AMD, by encouraging individuals to use fixation loci in the two eyes that have similar function. We start by examining the potential for depth perception in Aim 1. This requires mapping the regions of residual function in the two eyes to determine if there are corresponding points in the periphery that can subserve depth perception. In Aim 2 we determine whether observers are able to combine information from the two eyes (a necessary prerequisite for stereopsis) and whether they have any degree of depth perception. In Aim 3 we test the hypothesis that individuals with AMD are able to use different fixation loci for different tasks. We take two approaches to encourage observers to use retinal loci that are functionally equivalent and in corresponding locations in the two eyes, so they can provide a substrate for depth perception. We first artificially equate the pattern of vision loss in the two eyes and allo observers to practice coordinated eye movements. We then determine whether they use these corresponding fixation locations in an eye-hand coordination task that benefits from depth information. If indeed the choice of fixation location is task- dependent, we expect that practice with these two tasks will improve binocular correspondence and potentially lead to a recovery of stereopsis.