Load-related modulation of cutaneous reflexes in the tibialis anterior muscle during passive walking in humans
Load-related modulation of cutaneous reflexes in the tibialis anterior muscle during passive walking in humans
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DOI：
10.1111/j.1460-9568.2008.06120.x
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发表时间：
2008-03-01
影响因子：
3.4
通讯作者：
Nakazawa, Kimitaka
中科院分区：
文献类型：
--
作者：
Nakajima, Tsuyoshi;Kamibayashi, Kiyotaka;Nakazawa, Kimitaka
虽然皮肤反射被认为是强烈的调制在一个相位依赖的方式在人类和猫行走，它是不清楚是否运动相关的或负载敏感的传入反馈在调节这种调制中起着更重要的作用。为了解决这个问题，在人类中，我们研究了调制的皮肤反射在胫骨前肌（TA）的17名受试者在被动行走的负载（0%，33%，66%卸载体重）和没有负载（100%卸载）。这些行走任务是被动地进行机器人步态训练系统。在步行周期的10个不同阶段记录了电刺激胫骨远端（Tib）和腓浅神经（SP）引起的TA皮肤反射，并分析了中潜伏期反应（MLR，70-120 ms）。在负重行走过程中，由胫骨神经刺激诱导的MLR的幅度在后期至早期摆动阶段强烈增加，而与负荷量无关（相位调制），这种现象也发生在TA中没有背景肌电图的情况下。在站立早期，SP神经刺激后MLR的主要抑制在站立晚期变为易化。相比之下，无论是胫骨或SP神经刺激后的MLR没有在所有调制的步行阶段在空载行走（100%卸载）和站立。这些结果表明，在音乐会与节奏的下肢运动的负载相关的传入信息的阶段性变化中起着关键作用，在步行过程中调节皮肤反射。
Although cutaneous reflexes are known to be strongly modulated in a phase-dependent manner during walking in both human and cat, it is not clear whether the movement-related or the load-sensitive afferent feedback plays a more important role in regulating this modulation. To address this issue in humans, we investigated modulation of the cutaneous reflex in the tibialis anterior muscles (TA) of 17 subjects during passive walking with a load (0%, 33%, 66% unloading of body weight) and without a load (100% unloading). These walking tasks were performed passively with a robotic gait trainer system. Cutaneous reflexes in TA, elicited by electrical stimulation to the distal tibial (Tib) and superficial peroneal (SP) nerves, were recorded during 10 different phases of the walking cycle, and the middle latency responses (MLR, 70-120 ms) were analysed. During loaded walking, the magnitudes of the MLR induced by Tib nerve stimulation were strongly increased during the late stance-to-early swing phase irrespective of the amount of load (phase modulation), a phenomenon that also occurred without background electromyogram in the TA. Predominant suppression of the MLR following SP nerve stimulation at the early stance phase changed to facilitation at the late stance. By contrast, the MLR following either Tib or SP nerve stimulation was not at all modulated by the stepping phase during both unloaded walking (100% unloading) and standing. These results suggest that phasic changes in the load-related afferent information in concert with rhythmic lower limb movement play a key role in modulating cutaneous reflexes during walking.