CONTROL PROPERTIES OF AGED HUMAN MOTOR UNITS

老年人体运动单位的控制特性

• 批准号: 3121573
• 负责人: GARY P KAMEN
• 金额: $ 7.69万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-09-01 至 1994-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3121573
• 关键词: action potentials; aging; balance; computer data analysis; electrodes; motor neurons; muscle contraction; neural recruitment; neuromuscular function; neuromuscular system; neuromuscular transmission; proprioception /kinesthesia; respiratory muscles

DESCRIPTION: (Investigator's Abstract) The objective of this proposal is to determine what strategies aged adults use to control motorneuron firing. Preliminary work by the Principal Investigator suggests that the elderly may use alternative schemes for controlling motorneurons. For example, unusual derecruitment behavior of motor units, increased synchronization in the firing of motor units and unusual occurrence of doublet firing have been observed. In addition, work from other laboratories has shown loss of motor units with age despite the need to maintain force and precision in daily movements. Experiments are proposed to address the following key questions: 1) What strategies do older adults use to activate motor units during voluntary muscle contraction? 2) Do synergistic and antagonistic muscles adopt alternative strategies for motor action in older individuals? 3) What motor unit control strategies do older adults use to respond to sudden distrubances in balance? The experiments described in this proposal will be conducted in young and old adults using the first dorsal interosseous and anterior tibialis muscle groups during voluntary effort ranging up to 100 percent of maximal voluntary strength. Discharges of single motor units will be recognized using a specialized quadrifilar needle electrode and a computer aided technique to decompose the composite signal into individual motor unit firing trains. The long term goal is to determine whether an alternative motor control strategy is used to maintain optimal motor activity in the elderly.

描述：（研究者摘要）该提案的目标是 确定老年人使用什么策略来控制运动神经元放电。 首席研究员的初步工作表明，老年人 可以使用替代方案来控制运动神经元。 例如， 运动单位异常的去征行为，增加同步性 运动单位的放电和不寻常的双联放电的发生 被观察到。 此外，其他实验室的工作表明， 尽管需要保持力量和精度，但运动单位随着年龄的增长 日常运动。 建议进行实验来解决以下关键问题 问题：1）老年人使用什么策略来激活运动单位 随意肌收缩时？ 2）发挥协同作用和拮抗作用 老年人的肌肉采用替代策略进行运动动作吗？ 3) 老年人使用什么运动单位控制策略来应对 突然失去平衡？ 本提案中描述的实验 将使用第一背侧在年轻人和老年人中进行 自愿努力期间骨间肌群和胫骨前肌群 范围高达最大自愿强度的 100%。 排放量 单个运动单位将使用专门的四线识别 针电极和计算机辅助技术来分解复合材料 将信号发送到各个运动单元发射序列中。 长期目标是 确定是否使用替代电机控制策略来维持 老年人的最佳运动活动。