Vilis T, Cooke J D
Exp Brain Res. 1976 Jun 18;25(3):247-54. doi: 10.1007/BF00234016.
Electromyographic (EMG) reflex responses were examined in the biceps muscle of awake Cebus monkeys trained to resist perturbations of a handle with their forearm. In particular responses at latencies of 15-20 msec (M1) and 40-55 msec (M2), thought to correspond to segmental and suprasegmental reflex pathways respectively, were studied. The experiments demonstrated that the magnitude of the M1 response was large, as compared to M2, only when the muscle was tonically active and small perturbations were applied. For larger perturbations the magnitude of M1 saturated and the M2 response became functionally significant, its magnitude being directly related to the magnitude of the perturbation. By means of delayed reductions in torque, the magnitude of this M2 response was also shown to be very sensitive to changes in facilitatory drive provided by segmental pathways.
在经过训练能用前臂抵抗手柄扰动的清醒僧帽猴的肱二头肌中检测肌电图（EMG）反射反应。特别研究了潜伏期为15 - 20毫秒（M1）和40 - 55毫秒（M2）的反应，它们分别被认为对应于节段性和节段上反射通路。实验表明，只有当肌肉处于紧张性活动且施加小扰动时，M1反应的幅度才比M2大。对于较大的扰动，M1反应的幅度达到饱和，M2反应在功能上变得显著，其幅度与扰动的大小直接相关。通过延迟扭矩降低，还表明这种M2反应的幅度对节段性通路提供的易化驱动变化非常敏感。
