Perceptual Mechanisms of Visuospatial Orientation

视觉空间定向的感知机制

• 批准号: 7662358
• 负责人: CHARLES J DUFFY
• 金额: $ 29.72万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-15 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7662358
• 关键词: Affect; Age; Aging; Alzheimer' s Disease; Atrophic; Automobile Driving; Behavior; Characteristics; Cognition; Competence; Coupled; Cues; Disease; Disorientation; Elderly; Failure; Foundations; Frequencies; Goals; Head; Head Movements; Impairment; Independent Living; Lead; Learning; Link; Measures; Methods; Monitor; Motion; Movement; Neurons; Neuropsychological Tests; Patients; Pattern; Perception; Performance; Positioning Attribute; Process; Property; Relative (related person); Reliance; Research Personnel; Role; Route; Self Perception; Series; Signal Transduction; Simulate; Site; Speed; Stimulus; Syndrome; Testing; Time; Travel; Visual; Visual Motion; Visuospatial; Work; age effect; base; design; middle age; neuromechanism; optic flow; patient safety; response; sensory integration; skills; spatial integration; spatiotemporal; therapeutic target; visual process; visual processing; visual stimulus

DESCRIPTION (provided by applicant): Navigational impairments force Alzheimer's disease (AD) patients to abandon driving and independent living. We hypothesize that navigational impairments in aging and AD reflect failures of the neural mechanisms supporting the spatial and temporal integration of visual cues. We suggest that specific navigational deficits reflect the reliance of particular navigational skills on different segments of the visual spatiotemporal spectrum. To test these ideas, we will characterize visual processing in aging and AD linked to three fundamental navigational behaviors: heading estimation, route perception, and path integration. We have previously linked optic flow perceptual deficits to navigational impairments in AD. These patients show combined impairments in the spatial and temporal integration of visual stimuli. We now propose a comprehensive test of optic flow's role in navigation by characterizing links between specific navigational skills and the spatiotemporal composition of optic flow stimuli. We will apply spatial and temporal filters to optic flow simulating self-movement as subjects engage in a series of two-alternative forced-choice tasks designed to measure their sensitivity to the direction, speed, and distance of simulated self-movement. These studies will be coupled with detailed navigational and neuropsychological tests. In three Specific Aims, we will study: 1) Heading estimation, as the ability to indicate the direction, speed, and distance of self-movement. 2) Route perception, as the ability to discriminate relative directions, speeds, and distances traveled on a two-segment route. 3) Path integration, as the ability to combine directions, speeds, and distances for an optimal route of return to the origin. In each aim, we will manipulate the spatiotemporal composition of the stimuli to probe the relationship between perception and navigation. This work will lead to a new understanding of the perceptual foundations of navigation. We will test the relationship between spatiotemporal integration and perceptual processing for different navigational tasks in the context of navigational impairments in aging and AD. This will contribute to approaches for monitoring the progression of AD, evaluating patients' safety for functional independence, and assessing new treatments.

描述（由申请人提供）：导航障碍迫使阿尔茨海默病（AD）患者放弃驾驶和独立生活。我们假设衰老和 AD 中的导航障碍反映了支持视觉线索时空整合的神经机制的失败。我们认为，特定的导航缺陷反映了特定导航技能对视觉时空频谱不同部分的依赖。为了测试这些想法，我们将描述衰老和 AD 中与三种基本导航行为相关的视觉处理：航向估计、路线感知和路径整合。 我们之前已经将 AD 中的视流知觉缺陷与导航障碍联系起来。这些患者在视觉刺激的空间和时间整合方面表现出综合障碍。我们现在提出通过表征特定导航技能与光流刺激的时空组成之间的联系来对光流在导航中的作用进行全面测试。当受试者参与一系列旨在测量他们对模拟自我移动的方向、速度和距离的敏感度的两个可选强制选择任务时，我们将应用空间和时间滤波器来模拟自我移动的光流。这些研究将与详细的导航和神经心理学测试相结合。 在三个具体目标中，我们将研究： 1）航向估计，即指示自我移动的方向、速度和距离的能力。 2）路线感知，即区分两段路线上相对方向、速度和行驶距离的能力。 3) 路径整合，即结合方向、速度和距离以获得返回原点的最佳路线的能力。在每个目标中，我们将操纵刺激的时空组成来探索感知和导航之间的关系。 这项工作将带来对导航感知基础的新理解。我们将在衰老和 AD 导航障碍的背景下测试不同导航任务的时空整合和感知处理之间的关系。这将有助于制定监测 AD 进展、评估患者功能独立的安全性以及评估新疗法的方法。