Zehr E P, Collins D F, Chua R
Neurophysiology Laboratory, E-401 VVC, Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, T6G 2H9, Canada.
Exp Brain Res. 2001 Oct;140(4):495-504. doi: 10.1007/s002210100857.
There is some discrepancy over the extent to which reflex pathways from different cutaneous nerves in the hand and foot link the cervical and lumbar spinal cord in neurologically intact humans. The present experiments were designed to determine whether stimulation of a cutaneous nerve in the foot or in the hand evoked reflexes in the non-stimulated limbs (interlimb reflexes). Reflexes were elicited by stimulating (5x1-ms pulses at 300 Hz) the superficial peroneal (SP; innervates the foot dorsum) or superficial radial (SR; innervates the dorsolateral portion of the hand) nerve while subjects (n=10) performed focused contractions of different upper and lower limb muscles. Reflex responses were divided into early (<75 ms), middle (75-120 ms), and late (>120 ms) epochs as determined from averages of 50 sweeps of stimulus-locked electromyographic activity. Significant interlimb reflexes were found at the early latency in 44/106 and 44/103 muscles sampled after SP and SR nerve stimulation, respectively. At the middle latency, significant interlimb reflexes were seen in 89/106 and 87/103 muscles sampled after SP and SR nerve stimulation, respectively. Interlimb reflexes were seen when stimulating at the wrist (i.e. SR nerve) and when stimulating at the ankle (i.e. SP nerve) with an equal probability. The results show that interlimb cutaneous reflexes are widely distributed in humans. The mean latency of the earliest response was quite short and may be mediated by a propriospinal pathway. Functionally, these pathways may provide a substrate for transferring information to coordinate movements between the limb segments.
在神经功能正常的人类中，手部和足部不同皮神经的反射通路在多大程度上连接颈脊髓和腰脊髓，存在一些差异。本实验旨在确定刺激足部或手部的皮神经是否会在未受刺激的肢体中诱发反射（肢体间反射）。在受试者（n = 10）进行不同上肢和下肢肌肉的集中收缩时，通过刺激（300 Hz的5个1毫秒脉冲）腓浅神经（SP；支配足背）或桡浅神经（SR；支配手的背外侧部分）来诱发反射。根据50次刺激锁定肌电图活动的平均值，将反射反应分为早期（<75毫秒）、中期（75 - 120毫秒）和晚期（>120毫秒）阶段。在刺激SP和SR神经后采样的106块和103块肌肉中，分别有44块和44块肌肉在早期潜伏期出现显著的肢体间反射。在中期潜伏期，刺激SP和SR神经后采样的106块和103块肌肉中，分别有89块和87块肌肉出现显著的肢体间反射。在手腕（即SR神经）和脚踝（即SP神经）刺激时出现肢体间反射的概率相等。结果表明，肢体间皮肤反射在人类中广泛分布。最早反应的平均潜伏期相当短，可能由脊髓固有通路介导。在功能上，这些通路可能为传递信息以协调肢体节段之间的运动提供了一个基础。
