Optic Flow and Spatial Navigation in Parkinson's Disease

帕金森病的光流和空间导航

• 批准号: 6618615
• 负责人: Alice Cronin-Golomb
• 金额: $ 18.78万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-15 至 2005-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6618615
• 关键词: Parkinson's disease; age difference; behavioral /social science research tag; clinical research; cognition disorders; functional ability; gait; human old age (65+); human subject; longitudinal human study; medical complication; neural information processing; orientation; posture; questionnaires; sensorimotor system; space perception; vision tests; visual perception; young adult human (21-34)

DESCRIPTION (provided by applicant): Parkinson's disease (PD) is a common age-related neurodegenerative disorder in which multiple aspects of visuospatial cognitive function are impaired, including spatial navigation. Deficits in spatial navigation arise from pathological changes in high-order association areas of the brain but also from defective input from lower-level visual processing areas, including those that mediate optic flow. Optic flow refers to the radial visual patterns that indicate a person's direction of self-movement and maintain gait and postural integrity. The status of optic flow perception in PD is unknown, as is its relation to PD deficits in spatial navigation, such as the inability to maintain a straight path while walking. We propose to examine optic flow perception in PD and its relation to spatial navigation. A critical focus is on the side of onset of motor impairment, contralateral to the hemisphere with predominant basal ganglia dysfunction. PD usually has unilateral onset, and many visuospatial abnormalities arise from right-hemisphere dysfunction. Our preliminary studies suggest that PD patients with left motor onset experience spatial compression of the left visual hemifield, which affects their ability to understand spatial relations and to use spatial information for navigation. We predict that deficits in optic flow perception underlie this perceived spatial compression. Specifically, hemifield differences in optic flow velocities lead patients to misperceive a straight path as curved toward the compressed side of space, and they "correct" their trajectory by walking a curved path. We propose to investigate optic flow and spatial navigation in 18 patients with left-onset PD, 18 with right-onset PD, 18 healthy elderly adults, and 18 healthy young adult adults. Our specific aims are: (1) To manipulate the speed of optic flow in the two visual hemifields and measure each participant's perception of relative speed, which is associated with perceived direction of self-motion. (2) To relate optic flow to spatial navigation. We will use a head-mounted system that provides virtual visual input and records the orientation and spatial position of the participant while walking through veridical space. (3) To relate optic flow and spatial navigation to daily function, as assessed with questionnaires. Our project is conceptually innovative in proposing optic flow deficiencies as a cause of problems of spatial navigation in PD and will generate pilot data in this potentially important area. We have forged novel collaborations between experts in visual psychophysics, behavioral neuroscience, biomedical engineering, and physical therapy to accomplish the goals of this project.

描述（由申请人提供）：帕金森病（PD）是一种常见的与年龄相关的神经退行性疾病，其中视觉空间认知功能的多个方面受损，包括空间导航。空间导航的缺陷源于大脑高阶关联区域的病理变化，但也源于低级视觉处理区域（包括那些介导视流的区域）的输入缺陷。光流是指指示人自我运动方向并保持步态和姿势完整性的径向视觉模式。 PD 中的光流感知状态尚不清楚，其与 PD 空间导航缺陷（例如行走时无法保持直线路径）的关系也是未知的。我们建议研究 PD 中的光流感知及其与空间导航的关系。重点关注运动障碍发作一侧，即基底神经节功能障碍占主导地位的半球的对侧。 PD通常单侧发病，许多视觉空间异常是由右半球功能障碍引起的。我们的初步研究表明，左侧运动发作的帕金森病患者的左视觉半视野受到空间压缩，这影响了他们理解空间关系和使用空间信息进行导航的能力。我们预测光流感知的缺陷是这种感知空间压缩的基础。具体来说，光流速度的半视野差异导致患者将直线路径误认为是朝向空间压缩侧弯曲的，并且他们通过行走弯曲路径来“纠正”自己的轨迹。我们建议对 18 名左发性 PD 患者、18 名右发性 PD 患者、18 名健康老年人和 18 名健康年轻人进行视流和空间导航研究。我们的具体目标是：（1）操纵两个视觉半场中的光流速度，并测量每个参与者对相对速度的感知，这与感知的自我运动方向相关。 (2) 将光流与空间导航联系起来。我们将使用头戴式系统，该系统提供虚拟视觉输入并记录参与者在真实空间中行走时的方向和空间位置。 (3) 通过问卷评估将光流和空间导航与日常功能联系起来。我们的项目在概念上具有创新性，提出光流缺陷是局部放电空间导航问题的一个原因，并将在这个潜在的重要领域生成试点数据。我们在视觉心理物理学、行为神经科学、生物医学工程和物理治疗领域的专家之间建立了新颖的合作，以实现该项目的目标。