肌肉收缩性质直接影响脊柱运动神经元的共享突触输入
Hélio V Cabral1, J Greig Inglis1, Alessandro Cudicio1
1Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy.
The Journal of physiology
|May 6, 2024
概括
改变肌肉长度会改变神经振荡,减少突触输入和力输出中的α带活动. 这表明肌肉长度会影响神经控制和力稳定性.
科学领域:
- 神经科学是一个神经科学.
- 发动机控制器的控制器
- 生物力学 生物力学
背景情况:
- 对α运动神经元的共享突触输入会产生振荡,这些振荡可以充当噪声,损害自愿力产生.
- 了解肌肉长度等生理因素如何影响这些振荡对于理解运动控制至关重要.
研究的目的:
- 研究改变肌肉长度对脊柱运动神经元常见突触振荡的影响,特别是在生理震频段 (5-15 Hz) 内.
- 为了确定肌肉长度的变化是否会影响神经振荡传输到肌肉力输出.
主要方法:
- 高密度表面电肌图 (HDsEMG) 记录了从小腿前肌在低水平的背部屈曲时在两个脚关节角度 (90°和130°).
- HDsEMG信号被分解成动力单元尖峰列车,以分析三角形,α和β频段的连贯性.
- 在震动带内量化了力稳定性和光谱功率;记录了引起的抽,以评估肌肉收缩性质.
主要成果:
- 当肌肉长度增加 (从90°到130°的脚角度) 时,突触输入和力输出中的α波段振荡显著减少.
- 没有观察到德尔塔或贝塔波段振荡的显著变化,也没有观察到两个肌肉长度之间的力量稳定性.
- 引起的抽在较长的肌肉长度下持续时间较长,这表明肌肉具有增强的低通特性.
结论:
- 增加肌肉长度可以增强肌肉的低通能力,调节来自Ia afferent反循环的振荡.
- 由于肌肉长度而导致的外周收缩性质的变化显著影响了共享的突触输入如何转化为肌肉力量.
- 这项研究强调了肌肉生物力学和神经振荡在运动控制中的相互作用.
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