Testing the effects of visual field on perceptual organization as a potential source of unexplained visual dysfunction in macular degeneration

测试视野对知觉组织的影响作为黄斑变性中不明原因视觉功能障碍的潜在来源

基本信息

批准号：
9898382
负责人：
CATHLEEN M MOORE
金额：
$ 18.77万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2022-03-31
项目状态：
已结题

项目摘要

Project Summary The goal of this work is to characterize changes in visual processes that transform the 2-dimensional retinal image into object-based 3-dimensional representations of the world as a function of location within the visual field. These processes—referred to collectively as perceptual organization—are critical to the success of more complex visual tasks including important everyday tasks like reading, recognizing individuals, and following dynamic events on a screen or in the world. The underlying neurophysiology of the most fundamental components of perceptual organization suggest the hypothesis that perceptual organization is relatively poor for information in peripheral regions of the visual field compared to central regions. We will test that hypothesis in this work. Part of the significance of this work is that macular degeneration, which is the leading cause of blindness in people over the age of 65, and is expected to affect nearly 2 million individuals in the U.S. by 2020, is characterized by progressive loss of vision in central regions of the visual field. Individuals with macular degeneration therefore have to learn to rely on information in their periphery, and many interventions for the disease focus on increasing the size of peripheral information to compensate for known decreases in spatial resolution with eccentricity. Despite the success of these interventions to improve sensitivity to peripheral stimuli, many patients continue to suffer dysfunction in more complex, and critical for everyday life, tasks such as reading and recognizing faces. We hypothesize that an important part of this residual dysfunction is caused by the need to rely on peripheral perceptual organization which yields relatively poor 3D models of the world, even if edges and other low-level features are perfectly discriminable. This project will (1) quantify a set of four basic perceptual organization processes that are directly relatable to the simple neurophysiological mechanisms that have been identified and that provide motivation for the basic hypothesis, (2) test the hypothesis that an important downstream process that depends on perceptual organization – object-based attention — also decreases in effectiveness in more peripheral regions of the visual field and (3) test the hypothesis that changes in perceptual organization as a function of location in the visual field can predict changes in object-based attention within individual observers. If this work provides support for the basic hypotheses being tested, then follow-up work will extend the measurements to patients with central visual-field loss and ask whether their specific dysfunctions can be accounted for by reliance on relatively poor perceptual organization and if so, seek to develop interventions that either improve or compensate specifically for this dependence.

项目概要这项工作的目标是表征视觉过程的变化，这些变化改变了二维将视网膜图像转换为基于对象的 3 维世界表征，作为图像中位置的函数这些过程（统称为感知组织）对于成功至关重要。更复杂的视觉任务，包括重要的日常任务，如阅读、识别个人和跟踪屏幕上或世界上的动态事件最底层的神经生理学。知觉组织的基本组成部分提出这样一个假设：知觉组织是与中心区域相比，视野外围区域的信息相对较差。这项工作的部分意义在于黄斑变性，即黄斑变性。导致 65 岁以上人群失明的主要原因，预计将影响近 200 万人到 2020 年，美国将出现这种情况，其特点是视野中央区域逐渐丧失视力。因此，患有黄斑变性的人必须学会依赖周围的信息，并且许多针对该疾病的干预措施都侧重于增加外围信息的大小以补偿尽管这些干预措施取得了成功，但已知偏心会导致空间分辨率下降。由于对周围刺激的敏感性增加，许多患者继续遭受更复杂且严重的功能障碍我们将日常生活中的任务（例如阅读和识别面孔）视为其中的重要组成部分。残余功能障碍是由于需要依赖外周知觉组织而引起的，而外周知觉组织产生的相对世界的 3D 模型很差，即使边缘和其他低级特征是完全可区分的。项目将 (1) 量化一组与组织直接相关的四个基本感知组织过程。已经确定的简单的神经生理学机制，为基本的神经生理学机制提供了动力假设，（2）检验假设，即依赖于感知的重要下游过程组织——基于对象的注意力——在更外围区域的效率也会降低视野和（3）检验知觉组织的变化作为位置函数的假设如果这项工作提供的话，视野可以预测个体观察者基于对象的注意力的变化。支持正在测试的基本假设，然后后续工作将把测量扩展到患者患有中央视野丧失的人，并询问他们的特定功能障碍是否可以通过依赖来解释知觉组织相对较差，如果是这样，寻求制定干预措施来改善或专门补偿这种依赖性。