Phase-dependent reflex reversal in human leg muscles during walking.
Phase-dependent reflex reversal in human leg muscles during walking.
复制标题
行走过程中人类腿部肌肉的相位依赖性反射逆转。
作者：
Jaynie F. Yang;R. Stein
1.行走时的反射反应是通过刺激人类踝关节处的胫神经引起的。通过监测来自内在足部肌肉的M波来控制刺激强度。在同侧胫骨前肌（TA）、比目鱼肌（SO）和股直肌（RF）中观察到反应。在50和90 ms之间的中间潜伏期观察到最可重复的反应。反应最有可能是皮肤起源，因为它们非常类似于刺激纯皮神经，腓肠神经的反应。2.中潜伏期反应的方向从兴奋到抑制的逆转，观察到第一次在单一的肌肉在行走。逆转的证据在所有三个肌肉检查和所有七个主题。3.站立时不能引起反射逆转。在中潜伏期，总观察到一种抑制，其幅度与刺激强度和背景激活水平呈线性关系。站立时的反应类似于行走时站立阶段的反应。这两项任务有一些共同的运动目标，似乎利用类似的反射途径。
1. Reflex responses during walking were elicited in humans by stimulation of the tibial nerve at the ankle. The stimulus intensity was controlled by monitoring the M-wave from an intrinsic foot muscle. Responses were observed in the ipsilateral tibialis anterior (TA), soleus (SO), and rectus femoris (RF) muscles. The most reproducible responses were observed at a middle latency between 50 and 90 ms. The responses were most likely of cutaneous origin, because they closely resembled the responses to stimulation of a purely cutaneous nerve, the sural nerve. 2. A reversal in the direction of the middle latency response from excitation to inhibition was observed for the first time within single muscles during walking. Evidence for a reversal was seen in all three muscles examined and in all seven subjects. 3. The reflex reversal could not be elicited in standing. An inhibition whose amplitude varied in a linear fashion with stimulus intensity and background activation level was always observed at middle latency. The responses elicited during standing resembled those during the stance phase of walking. The two tasks shared some common movement goals and appeared to make use of similar reflex pathways.