THE VISUAL REQUIREMENTS OF EVERYDAY TASKS

美国有100多万人视力严重受损。 他们的视力障碍是多样的，只有有限的 了解这些障碍如何影响日常任务的执行 比如散步和阅读。NEI及其赞助的几个工作坊 发现有必要对日常生活中的视觉需求进行研究 任务。 我们试图确定视觉能力的哪些方面可以在 预测移动性能的实验室。部分和正常视力 受试者将参与其中。正常视力的受试者会戴护目镜。 以各种方式限制视力(视野限制、对比度 减少，空间频率切断)和不同程度。为所有人 受试者的残余视力将表现为对比敏感度。 和现场测量。受试者的机动性现在正在一个 室内错综复杂的泡沫橡胶柱子。容易随机化的迷宫允许 在受控条件下重复测试。我们将做这些实验 在几种亮度下。接下来我们将学习三个真实的移动性 步行环境：走在大学校园里，走在大自然中 在一所大学的教学楼里。其目的是确定 视觉能力的什么衡量标准可以预测移动性能。

More than a million people in the U.S. have severely impaired vision. Their visual impairments are diverse and there is only limited understanding of how these impairments affect performance of daily tasks such as walking and reading. The NEI and several workshops sponsored by it have identified a need for research on the visual requirements of everyday tasks. We seek to determine what aspects of visual capacity can be measured in the laboratory to predict mobility performance. Partially and normally sighted subjects will participate. Normally sighted subjects will wear goggles which restrict vision in various ways (field restriction, contrast reduction, and spatial-frequency cut off) and to various degrees. For all subjects, the residual vision will be characterized by contrast sensitivity and field measurements. Mobility of the subjects is now being tested in an indoor maze of foam rubber columns. The easily randomized maze allows repeated testing under controlled conditions. We will do these experiments at several luminances. Next we will study mobility in three real pedestrian environments: walking on the university campus, on a nature trail, and in a university classroom building. The aim is to determine what measurements of visual capacity will predict mobility performance.