Calvin-Figuière S, Romaiguère P, Gilhodes J C, Roll J P
Laboratoire de Neurobiologie Humaine, UMR 6562, CNRS-Université de Provence, Centre de Saint-Jérôme, Marseille, France.
Exp Brain Res. 1999 Feb;124(3):342-50. doi: 10.1007/s002210050631.
In humans, vibration applied to muscle tendons evokes illusory sensations of movement that are usually associated with an excitatory tonic response in muscles antagonistic to those vibrated (antagonist vibratory response or AVR). The aim of the present study was to investigate the neurophysiological mechanisms underlying such a motor response. For that purpose, we analyzed the relationships between the parameters of the tendon vibration (anatomical site and frequency) and those of the illusory movement perceived (direction and velocity), as well as the temporal, spatial, and quantitative characteristics of the corresponding AVRs (i.e., surface EMG, motor unit firing rates and activation latencies). Analogies were supposed between the characteristics of AVRs and voluntary contractions. The parameters of the AVR were thus compared with those of a voluntary contraction with similar temporal and mechanical characteristics, involving the same muscle groups as those activated by vibration. Wrist flexor muscles were vibrated either separately or simultaneously with wrist extensor muscles at frequencies between 30 and 80 Hz. The illusory movement sensations were quantified through contralateral hand-tracking movements. Electromyographic activity from the extensor carpi radialis muscles was recorded with surface and intramuscular microelectrodes. The results showed that vibration of the wrist flexor muscle group induced both a kinesthetic illusion of wrist extension and a motor response in the extensor carpi radialis muscles. Combined vibration of the two antagonistic muscle groups at the same frequency evoked neither kinesthetic illusion nor motor activity. In addition, vibrating the same two antagonistic muscle groups at different frequencies induced both a kinesthetic illusion and a motor response in the muscle vibrated at the lowest frequency. The surface EMG amplitude of the extensor carpi radialis as well as the motor unit activation latency and discharge frequency were clearly correlated to the parameters of the illusory movement evoked by the vibration. Indeed, the faster the illusory sensation of movement, the greater the surface EMG in these muscles during the AVRs and the sooner and the more intense the activation of the motor units of the wrist extensor muscles. Moreover, comparison of the AVR with voluntary contraction showed that all parameters were highly similar. Mainly slow motor units were recruited during the AVR and during its voluntary reproduction. That the AVR is observed only when a kinesthetic illusion is evoked, together with the similarities between voluntary contractions and AVRs, suggests that this vibration-induced motor response may result from a perceptual-to-motor transformation of proprioceptive information, rather than from spinal reflex mechanisms.
在人类中，施加于肌腱的振动会引发虚幻的运动感觉，这些感觉通常与被振动肌肉的拮抗肌中的兴奋性紧张性反应相关（拮抗肌振动反应或AVR）。本研究的目的是探究这种运动反应背后的神经生理机制。为此，我们分析了肌腱振动参数（解剖部位和频率）与所感知的虚幻运动参数（方向和速度）之间的关系，以及相应AVR的时间、空间和定量特征（即表面肌电图、运动单位放电频率和激活潜伏期）。我们假设AVR的特征与随意收缩之间存在相似性。因此，将AVR的参数与具有相似时间和力学特征的随意收缩的参数进行了比较，随意收缩涉及与振动激活的肌肉群相同的肌肉群。分别或同时以30至80赫兹的频率对腕屈肌与腕伸肌进行振动。通过对侧手部追踪运动对虚幻运动感觉进行量化。使用表面电极和肌内微电极记录桡侧腕伸肌的肌电活动。结果表明，腕屈肌群的振动既诱发了腕伸展的运动错觉，也诱发了桡侧腕伸肌的运动反应。两个拮抗肌群以相同频率进行联合振动既未诱发运动错觉也未诱发运动活动。此外，以不同频率对相同的两个拮抗肌群进行振动，会在最低频率振动的肌肉中诱发运动错觉和运动反应。桡侧腕伸肌的表面肌电图幅度以及运动单位激活潜伏期和放电频率与振动诱发的虚幻运动参数明显相关。事实上，运动的虚幻感觉越快，在AVR期间这些肌肉中的表面肌电图就越大，腕伸肌运动单位的激活就越早且越强烈。此外，将AVR与随意收缩进行比较表明，所有参数都高度相似。在AVR及其随意再现过程中，主要募集的是慢运动单位。仅在诱发运动错觉时才观察到AVR，以及随意收缩与AVR之间的相似性，这表明这种振动诱发的运动反应可能源于本体感觉信息从感知到运动的转换，而非脊髓反射机制。
