上肢运动的神经策略:在增速动态收缩期间的运动单元控制
概括
动态运动期间的运动单元 (MU) 行为是神经康复和假肢的关键. 这项研究表明,更快的移动更多地依赖于调整动力单元的发射速度,而不是招募新单位.
科学领域:
- 神经科学是一个神经科学.
- 生物力学 生物力学
- 康复工程 康复工程 康复工程
背景情况:
- 在动态运动期间了解运动单元 (MU) 行为对于推进神经康复,假肢和人机界面 (HMI) 至关重要.
- 目前使用表面电肌图 (sEMG) 的机器学习方法可以对运动进行分类,但对神经控制机制的洞察力有限.
- 在动态任务中提取MU活动是具有挑战性的,因为信号非静止,与同位数收缩的既定方法不同.
研究的目的:
- 研究前臂 flexor 肌肉在不同速度和力量水平的动态收缩期间的运动单元控制策略.
- 为了确定是否通过招募更多的MU或通过增加已经活跃的MU的放电率来提高运动速度.
- 为了验证在动态运动期间跟踪MU的可行性,以改善神经技术.
主要方法:
- 使用高密度的sEMG分解来提取和跟踪MU活动.
- 在5°/s,10°/s和20°/s速度的动态收缩过程中分析了前臂曲肌肉.
- 收缩在最大自愿收缩力水平的15%和25%进行.
主要成果:
- 上肢的运动单元控制表现出明显的取决于速度的调制模式 (p < 0.05).
- 更高的运动速度主要是通过增加招募的MU的放电率来实现,而不是招募额外的MU.
- 该研究成功地证明了在动态收缩期间跟踪MU的可行性.
结论:
- 运动单元的招募和放电率策略是根据动态上肢任务的运动速度调节的.
- 在动态运动期间可以实现精确的MU跟踪,为更复杂的神经技术铺平了道路.
- 这些发现对开发更精确,更适应的辅助器件在假肢和HMI有影响.
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