Identifying potential cortical mechanisms responsible for gait impairment in older adult fallers

识别导致老年跌倒者步态障碍的潜在皮质机制

• 批准号: 10707873
• 负责人: Wouter Hoogkamer
• 金额: $ 18.99万
• 依托单位: UNIVERSITY OF MASSACHUSETTS AMHERST
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-30 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10707873
• 关键词: Address; Adult; Affect; Age; Area; Bilateral; Brain; Communities; Complex; Data; Development; Elderly; Environment; Exhibits; Fall prevention; Female; Gait; Goals; Health; Hemoglobin; Home; Impairment; Individual; Intervention; Knowledge; Length; Literature; Magnetic Resonance Imaging; Measures; Mediating; Mediation; Mediator; Medical Care Costs; Mission; Morbidity - disease rate; Motion; National Institute on Aging; Parietal Lobe; Performance; Prefrontal Cortex; Prevention program; Process; Public Health; Qualifying; Quality of life; Recording of previous events; Reporting; Resolution; Role; Specific qualifier value; Stimulus; Task Performances; Taxes; Time; Translating; United States National Institutes of Health; Visual; Walking; With laterality; Work; age effect; age related; early detection biomarkers; environmental change; fall risk; falls; fear of falling; frontal lobe; functional near infrared spectroscopy; gait examination; human old age (65+); improved; injury-related death; innovation; interdisciplinary approach; mortality; novel; preventive intervention; theories; therapeutic target; treadmill; visual processing; visual stimulus; young adult

Project Summary Insufficient knowledge about the cortical mechanisms of gait impairment and fall risk in older adults limits the development of effective fall prevention interventions. In order to improve the current gait assessments and interventions in older adults, a more complete quantification of gait performance is required. Current quantification of cortical activity during gait is mostly limited to the prefrontal cortex (PFC) and young adults. The lack of information about the posterior parietal cortex (PPC; visual processing of orientation and motion of the body in space) activity during gait further limits the interpretability of the current fall literature. Older adults' visual processing is slower compared to young adults, therefore, establishing the PPC's role in gait for older adult fallers and non-fallers is critical for understanding the role of the PPC in fall risk. The proposed study's significant contributions include defining cortical activity during a visually complex gait task in older adults and establish how cortical activity affects the relationship between gait and fall predictors in older adult fallers and non-fallers. This contribution is significant because it will identify the unknown roles of the PPC and PFC during visually complex gait performance in older adult fallers and non-fallers, which will guide more effective fall prevention interventions. This proposed study is innovative because it quantifies PPC activity during a visually complex gait task that requires constant visual processing, mimicking gait demands in the home and community environments. The primary purpose of this proposal is to compare cortical activity in the PPC and PFC and key gait metrics in young, healthy older and older adult fallers during increasingly complex gait tasks and elucidate the effect PPC and PFC activity have on the relationship between gait and fall predictors in older adult fallers and non-fallers. This proposal addresses the following specific aims: Aim 1: Effects of age and fall status on PPC and PFC activity during gait Hypothesis 1: Older adults will have increased oxy- and decreased deoxygenated hemoglobin concentrations in the PPC and PFC during gait and gait variability, and reduced dynamic stability and step adjustment accuracy than young adults. Older adult fallers will exhibit the most cortical activity and gait variability, and least dynamic stability and step adjustment accuracy. PPC activity from over ground to stepping-stone treadmill gait will be greatest for the older adult fallers, as they will be unable to swiftly process the added visual stimuli. Aim 2: Mediation of the gait performance and fall predictor relationship by cortical activity Hypothesis 2: The relationship between gait performance and falls has been examined, however, how cortical activity mediates this relationship is unknown. Cortical activity, especially PPC activity, will be a significant mediator to the relationship between gait performance (dynamic stability, variability, and step adjustment accuracy) and fall predictors (fall history and fear of falling) in older adults. This will be the first rigorous analyses of gait performance, PPC and PFC activity, and fall predictors in older adult fallers and non-fallers.

项目概要 对老年人步态障碍和跌倒风险的皮质机制了解不足限制了 制定有效的跌倒预防干预措施。为了改进当前的步态评估和 对老年人进行干预时，需要对步态表现进行更完整的量化。当前的 步态期间皮质活动的量化主要限于前额皮质（PFC）和年轻人。 缺乏有关后顶叶皮层（PPC；视觉处理方向和运动的信息） 步态期间的身体在空间中的活动进一步限制了当前秋季文献的可解释性。年长的 与年轻人相比，成年人的视觉处理速度较慢，因此，确定 PPC 在步态中的作用 老年人跌倒者和非跌倒者对于了解 PPC 在跌倒风险中的作用至关重要。拟议的 研究的重大贡献包括定义老年人视觉复杂步态任务期间的皮质活动 成年人，并确定皮质活动如何影响老年人的步态和跌倒预测因素之间的关系 跌倒者和非跌倒者。这一贡献意义重大，因为它将识别 PPC 的未知角色和 PFC 在老年人跌倒者和非跌倒者的视觉复杂步态表现中，这将指导更多 有效的跌倒预防干预措施。这项拟议的研究具有创新性，因为它量化了 PPC 活动 在需要持续视觉处理的视觉复杂步态任务中，模仿 家庭和社区环境。该提案的主要目的是比较皮层活动 越来越多的年轻、健康老年人和老年跌倒者的 PPC 和 PFC 以及关键步态指标 复杂的步态任务并阐明 PPC 和 PFC 活动对步态与跌倒之间关系的影响 老年人跌倒者和非跌倒者的预测因素。该提案旨在实现以下具体目标： 目标 1：年龄和跌倒状态对步态期间 PPC 和 PFC 活动的影响 假设 1：老年人体内的氧合血红蛋白浓度升高，脱氧血红蛋白浓度降低 步态和步态变异期间的 PPC 和 PFC，并降低动态稳定性和步调精度 比年轻人。老年跌倒者将表现出最多的皮质活动和步态变异性，并且最少 动态稳定性和步调精度。 PPC 活动从地面到踏脚石跑步机步态 对于老年跌倒者来说是最好的，因为他们将无法快速处理增加的视觉刺激。 目标 2：通过皮质活动调节步态表现和跌倒预测关系 假设 2：步态表现与跌倒之间的关系已被检验，然而，皮质如何影响跌倒？ 活动介导这种关系尚不清楚。皮质活动，特别是 PPC 活动，将是一个重要的 步态表现（动态稳定性、变异性和步数调整）之间关系的中介 准确性）和老年人跌倒预测因素（跌倒史和跌倒恐惧）。这将是第一个严格的 对老年人跌倒者和非跌倒者的步态表现、PPC 和 PFC 活动以及跌倒预测因素进行分析。