Neural correlates of postural dyscontrol in frail elderly

描述(申请人提供)：老年人表现出的姿势不稳定会增加跌倒和受伤的风险，导致更大的发病率和生活质量下降。对于那些年老体弱的人来说，这些变化和由此产生的影响甚至更大。本项目的目的是确定踝关节周围肌肉的静态和动态控制在姿势不稳定中的作用，以及大脑、脊髓运动神经元和周围神经系统可能导致姿势控制障碍的机制。我们建议测量1)在新任务中控制脚踝力量的能力，2)在静态和动态任务中的姿势摆动，3)认知负荷、视觉运动反馈操作和本体感觉操作对力控制的影响，4)在力控制任务中单个脊髓运动神经元的放电，以及5)控制受损的功能相关性-在健康和虚弱的老年人。这些信息将增强对神经系统变化的了解，这些变化导致对姿势稳定性的控制受损，以及随之而来的身体功能变化。更多地了解那些变得虚弱的人所发生的变化，将有助于理解适用于改善越来越多的美国老年人生活质量的最佳干预措施。 与公共卫生相关：站立时站立不稳的老年人可能有更大的跌倒和严重受伤的风险。该项目将确定健康的老年和虚弱的老年成年人控制脚踝肌肉和站立姿势困难的一些原因。将在健康的老年人和虚弱的老年人中测量脚踝肌肉的控制情况。同样的人在站立时控制自己姿势的能力也将被测量，以及平衡和移动性。从脊髓到肌肉的信号将用电极测量。更多地了解衰老、虚弱的美国人神经系统的这些变化，将导致应用更有效的运动计划来对抗老年人的不稳定、虚弱和功能障碍。

DESCRIPTION (provided by applicant): The postural instability exhibited by older adults increases fall and injury risk, leading to greater morbidity and decreased quality of life. These changes and the resulting impact are even greater for those who become frail in old age. The purpose of this project is to determine the role of static and dynamic control of muscles surrounding the ankle in postural instability, and mechanisms in the brain, spinal motor neurons, and peripheral nervous system that may underlie the postural dyscontrol. We propose to measure 1) the ability to control ankle force during novel tasks, 2) postural sway during static and dynamic tasks, 3) the effects of cognitive load, visuomotor feedback manipulation, and proprioceptive manipulation on force control, 4) the discharge of single spinal motor neurons during force control tasks, and 5) the functional correlates of impaired control - in healthy and frail elderly adults. The information will enhance knowledge on the changes in the nervous system that lead to impaired control of postural stability, and the accompanying changes in physical function. A greater knowledge of the changes that occur in those who become frail will aid in understanding the best interventions to apply to improve quality of life for the growing number of elderly Americans. PUBLIC HEALTH RELEVANCE: Elderly adults who are less steady while standing may have a greater risk of falling and serious injury. This project will determine some reasons that healthy elderly and frail elderly adults have difficulty controlling their ankle muscles and standing posture. The control of ankle muscles will be measured in healthy elderly and frail elderly adults. The ability of the same individuals to control their posture while standing will also be measured, along with balance and mobility. The signals from the spinal cord to the muscle will be measured with electrodes. Greater knowledge of these changes in the nervous system of aging, frail Americans will lead to the application of more effective exercise programs to combat unsteadiness, frailty, and functional disability in the elderly.