Human stretch reflex pathways reexamined.
Human stretch reflex pathways reexamined.
复制标题
重新检查人类牵张反射通路。
作者：
U. Yavuz;N. Mrachacz‐Kersting;uz Sebik;M. B. Ünver;D. Farina;K. Türker
研究了人类受试者胫骨前肌运动单元对拉伸刺激的反射反应。使用三种类型的拉伸刺激（轻拍式，倾斜和保持，半正弦拉伸）。采用经典技术对单个运动单元的刺激诱导反应进行了分析，该技术包括根据运动单元的放电时间建立平均表面肌电图（SEMG）和刺激周围时间直方图（PSTH），以及根据单个运动单元的瞬时放电速率建立刺激周围频率图（PSF）。使用表面肌电和PSTH，轻拍样拉伸刺激平均诱导5个独立的反射反应。对于相同的单个运动单元数据，PSF技术表明轻拍刺激只引起三种反射反应。与使用类似轻拍的拉伸刺激的发现类似，斜坡和保持刺激在肌电图和PSTH中诱发了几个波峰和波谷。PSF分析显示放电率在峰值下而不是在低谷下真正增加。半正弦拉伸刺激诱发了长时间的兴奋，随后是表面肌电和PSTH的长时间沉默期。然而，放电率的增加持续了整个刺激时间，并在沉默期继续。考虑到运动神经元的放电速率与其接收到的有效突触电流具有很强的正线性关系，因此比其他间接测量方法更直接、更准确地反映了膜电位的变化。这项研究表明，人类拉伸反射的神经元通路不包括抑制通路。
Reflex responses of tibialis anterior motor units to stretch stimuli were investigated in human subjects. Three types of stretch stimuli were applied (tap-like, ramp-and-hold, and half-sine stretch). Stimulus-induced responses in single motor units were analyzed using the classical technique, which involved building average surface electromyogram (SEMG) and peristimulus time histograms (PSTH) from the discharge times of motor units and peristimulus frequencygrams (PSF) from the instantaneous discharge rates of single motor units. With the use of SEMG and PSTH, the tap-like stretch stimulus induced five separate reflex responses, on average. With the same single motor unit data, the PSF technique indicated that the tap stimulus induced only three reflex responses. Similar to the finding using the tap-like stretch stimuli, ramp-and-hold stimuli induced several peaks and troughs in the SEMG and PSTH. The PSF analyses displayed genuine increases in discharge rates underlying the peaks but not underlying the troughs. Half-sine stretch stimuli induced a long-lasting excitation followed by a long-lasting silent period in SEMG and PSTH. The increase in the discharge rate, however, lasted for the entire duration of the stimulus and continued during the silent period. The results are discussed in the light of the fact that the discharge rate of a motoneuron has a strong positive linear association with the effective synaptic current it receives and hence represents changes in the membrane potential more directly and accurately than the other indirect measures. This study suggests that the neuronal pathway of the human stretch reflex does not include inhibitory pathways.
有效突触电流可以通过神经元放电的测量来估计。
影响因子：
2.5
作者：
Powers,RK;Robinson,FR;Konodi,MA;Binder,MD
通讯作者：
Binder,MD
大的兴奋性和抑制性输入对运动神经元放电速率和概率的影响。
DOI：
10.1152/jn.1999.82.2.829
发表时间：
1999
期刊：
Journal of neurophysiology.
影响因子：
--
作者：
Turker,KS;Powers,RK
通讯作者：
Powers,RK