Neural mechanisms of anticipatory postural adjustment in human

人类预期姿势调整的神经机制

基本信息

批准号：
07680119
负责人：
KASAI Tatsuya
金额：
$ 1.34万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

A biomechanical and neurophysiological analysis of anticipatory postual adjustments associated with the early phase of a voluntary arm movement was carried out in normal subjects. Arm elevation, performed at maximal velocity, was studied with unilateral arm movement in freely and counterbalanced (suspended in a safety harness) standing humans. The ground reaction force of both legs, tengential acceleration of the shank and electromyographic (EMG) activity of the anterior deltoid (AD), biceps femoris (BF) and soleus (Sol) muscles were recorded. Sol H-reflex of both legs were also elicited. In this study, we systematically investigated biomechanical and EMG phenomena that precede and follow the onset of voluntary arm movements. Prior to and during the arm movement (i.e., AD activity), a sequence of EMG modofications occurred in ipsilateral BF and Sol muscles. Those modifications preceding BF activity included silent phases in Sol EMG and depression of Sol H-reflexes. By comparing EMG modifications with depression of the Sol H-reflex, we conclude that Ia and presynaptic inhibitory pathways do not play a specific role in those Sol H-reflex depression. Moreover, because Sol H-reflex depression occurs in both freely standing and counterbalanced postures, anticipatory postural adjustment appear to be preprogramd in the central neuvous systems unrelated to peripheral neural mechanisms. Since changes of EMG activities of ipsilateral BF and Sol appeared simultaneously and Sol H-reflex depressions were dependent on EMG activities of ipsilateral BF,control commands to anticipatory postural adjustment would excite BF and inhibit Sol.

对正常受试者进行了与自愿性臂运动的早期相关的预期后调整的生物力学和神经生理分析。在最大速度下进行的手臂抬高以自由和平衡（悬挂在安全带上）站立的人类中的单侧手臂运动进行了研究。两条腿的地面反应力，前三角肌（AD），二头肌股骨（BF）和soleus（sol）肌肉的弯曲加速度和肌电图（EMG）活性。也引起了双腿的Sol H反射。在这项研究中，我们系统地研究了在自愿运动之前并遵循自愿运动之前的生物力学和EMG现象。在手臂运动（即AD活性）之前，同侧BF和SOL肌肉中发生了一系列EMG模拟。 BF活性之前的这些修饰包括溶胶EMG中的无声阶段和溶胶H反射的抑郁。通过将EMG修饰与SOL H反射的抑郁症进行比较，我们得出结论，IA和突触前抑制途径在那些SOL H反射抑郁症中不发挥特定作用。此外，由于溶胶H反射抑郁症发生在自由站立和平衡的姿势中，因此预期的姿势调整似乎是与周围神经机制无关的中央新系统中的预编程。由于同侧BF和SOL的EMG活性的变化同时出现，Sol H反射抑制取决于同侧BF的EMG活性，因此控制命令的控制命令可以激发BF并抑制SOL。