Effects of visual fields on standing balance

描述（由申请人提供）：与年龄相关的视力障碍是公认的老年跌倒的危险因素。该试点研究的目的是确定中央和外围视野丧失对年轻人和老年人站立时整合与平衡相关的感觉信息能力的重要性。将考虑两种类型的视野丧失：a)健康的年轻人和老年人通过使用特殊设计的隐形眼镜而突然闭塞的中央和周围视野丧失；b)老年黄斑变性（AMD）和青光眼患者的慢性中央和周围视野丧失。我们的第一个假设是，在姿势稳定中，尤其是在老年人中，周边视觉比中央视觉更重要（目的1）。这将在健康的年轻人和老年人中测试使用隐形眼镜遮挡周围或中心视力，从而诱导急性周围或中心视力丧失的模型。我们的第二个假设是，在老年患者（AMD或青光眼）和患有急性中枢或外周视力丧失的健康老年人之间，整合对平衡很重要的感觉信息的能力是不同的（Aim #2）。这可归因于在患者中发现的中枢适应过程。将招募年龄在65岁至85岁之间的三组参与者：(1)10名接受眼部病变筛查的健康受试者，(2)10名晚期AMD患者，(3)10名晚期青光眼患者。此外，10名年龄在25至35岁之间的年轻受试者将参与拟议的实验。所有受试者将被筛查影响平衡的临床显著状况。符合条件的受试者将接受既成熟又新颖的平衡测试。适当构建的混合线性统计模型将适合于每个感兴趣的平衡变量，以确定影响

DESCRIPTION (provided by applicant): Age-related vision impairments are a well-acknowledged risk factor for geriatric falls. The goal of the proposed pilot research is to determine the importance of central and peripheral visual field loss on the ability to integrate balance-related sensory information during standing in young and older adults. Two types of visual field loss will be considered: a) sudden occlusion of the central and peripheral visual fiel loss through the use of specially-designed contact lenses in healthy young and older adults, and b) chronic central and peripheral visual field loss in older patients with age-related macular degeneration (AMD) and glaucoma. Our first hypothesis is that peripheral vision dominates over central vision in postural stabilization, particularly in older adults (Aim #1). This will be teste using contact lenses to occlude peripheral or central vision in healthy young and older adults, thus inducing a model of acute of peripheral or central vision loss. Our second hypothesis is that the ability to integrate sensory information important for balance will be different between older patients (AMD or glaucoma) and healthy older participants with acute central or peripheral visual losses (Aim #2). This can be attributed to central adaptation processes found in patients. Three groups of participants between the ages of 65 and 85 years will be recruited for participation: (1) ten healthy subjects screened for ocular pathologies, (2) ten patients with advanced AMD, (3) ten patients with advanced glaucoma. Additionally, ten young subjects between the ages of 25 and 35 years will participate in the proposed experiments. All subjects will be screened for clinically significant conditions that impact balance. Eligible subjects will undergo both well- established and novel balance tests. Appropriately constructed mixed linear statistical models will be fit to each of the balance variables of interest to determine the impact of acute and chronic visual field losses on the ability to integrate balance-related sensory information during standing.