Visuomotor contributions to unsteadiness in frail aging

视觉运动对衰弱衰老的不稳定的影响

• 批准号: 7434367
• 负责人: Brian L Tracy
• 金额: $ 6.48万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7434367
• 关键词: Adult; Aging; American; Computers; Condition; Cutaneous; Elderly; Exhibits; Feedback; Frail Elderly; Hand; Health; Individual; Intervention; Knowledge; Lead; Leg; Measures; Motor; Motor Neurons; Muscle; Nervous system structure; Process; Purpose; Quality of life; Reaction Time; Role; Sensory; Testing; Vision; age related; clinically relevant; frailty; functional decline; functional disability; neuromechanism; visual feedback; visual motor

DESCRIPTION (provided by applicant): The impaired control of muscle force in elderly adults can negatively impact quality of life. Various inputs to the motor neuron pool for a muscle could contribute to altered force control for healthy and frail elderly. The visuomotor contribution to force unsteadiness is not well characterized in healthy elderly and unknown in frail elderly. The limited information available is only for small hand muscles. The purposes are 1) to determine the contribution of visuomotor correction to force fluctuations in a hand muscle (FDI) and proximal leg muscle (KE) within the same individual young, health elderly, and frail elderly adults, 2) to quantify the role of central slowing and cutaneous sensory acuity in the impaired control, 3) to determine the functional significance of hand and leg muscle force fluctuations, and 4) to determine the visuomotor contribution to the variability of FDI and KE motor unit discharge. Young, healthy elderly and frail elderly adults will perform steady contractions under different visual feedback conditions to determine age-related differences in the processing of visuomotor information to maintain a steady muscle force. Reaction time and sensory acuity tests will determine the contribution of central slowing and sensory degradation. Hand dexterity and leg functional measures will provide a clinically relevant connection to function. The discharge of single motor units will be recorded in the FDI and KE muscles to provide information on a neural mechanism underlying the force fluctuations and changes with aging in two very different muscles. Although frail elderly adults exhibit neuromuscular and functional decline, mechanisms of force control in this group are not well understood. We hypothesize that frail elderly will exhibit a greater contribution of visuomotor processing, greater fluctuations in force, and greater motor unit variability, which will be explained in part by central slowing and sensory degradation. This project will determine some reasons that the elderly have more difficulty controlling their muscles. The control of different muscles will be measured in young, healthy elderly, and frail elderly adults to determine the role of impaired vision in the control of muscles. Greater knowledge of these changes in the nervous system of aging Americans can lead to the application of more effective intervention strategies to combat frailty and functional disability in the elderly.

描述（由申请人提供）：老年人肌肉力量控制受损可能对生活质量产生负面影响。对肌肉运动神经元池的各种输入可能有助于改变健康和虚弱老年人的力控制。视觉对力不稳定的贡献在健康老年人中没有很好的表征，在体弱老年人中未知。有限的信息仅适用于手部小肌肉。目的是1）确定视力矫正对同一个体年轻人、健康老年人和虚弱老年人中的手部肌肉（FDI）和近端腿部肌肉（KE）中的力波动的贡献，2）量化中枢减慢和皮肤感觉敏锐度在受损控制中的作用，3）确定手部和腿部肌肉力波动的功能意义，（4）确定视觉刺激对FDI和KE运动单位放电变异性的贡献。年轻、健康的老年人和体弱的老年人将在不同的视觉反馈条件下进行稳定的收缩，以确定与年龄相关的视觉信息处理差异，以保持稳定的肌肉力量。反应时间和感觉敏锐度测试将确定中枢减慢和感觉退化的贡献。手灵活性和腿部功能测量将提供与功能的临床相关连接。将在FDI和KE肌肉中记录单个运动单元的放电，以提供关于两种非常不同的肌肉中的力波动和随年龄变化的神经机制的信息。虽然年老体弱的成年人表现出神经肌肉和功能下降，在这组的力控制机制还没有很好地理解。我们假设，体弱的老年人将表现出更大的贡献的视觉处理，更大的波动力，更大的运动单位的变异性，这将部分解释为中央放缓和感觉退化。该项目将确定老年人更难控制肌肉的一些原因。将在年轻人、健康老年人和体弱老年人中测量不同肌肉的控制，以确定视力受损在肌肉控制中的作用。更多地了解美国老年人神经系统的这些变化可以导致应用更有效的干预策略来对抗老年人的虚弱和功能障碍。