Static and dynamic input-output relations of the feline medial gastrocnemius motoneuron-muscle system subjected to recurrent inhibition: a model study
Static and dynamic input-output relations of the feline medial gastrocnemius motoneuron-muscle system subjected to recurrent inhibition: a model study
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反复抑制下猫内侧腓肠肌运动神经元肌肉系统的静态和动态输入输出关系：模型研究
DOI：
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发表时间：
2003
影响因子：
1.9
通讯作者：
U. Windhorst
中科院分区：
文献类型：
--
作者：
T. Uchiyama;H. Johansson;U. Windhorst
摘要：脊髓反复抑制的生理功能仍然存在争议，因为在正常行为的动物身上观察到反复抑制在工作中的实验困难或不可能。本研究的目的是通过计算机模拟研究反复抑制在形成下行指令信号(DC)作为输入，运动神经元(MN)和Renshaw cell(RC)的放电率和肌肉力量作为输出之间的输入-输出关系中的作用。将重复抑制的空间(局部)分布从非均质性(如标准模型)改变为均质性，并不显著改变I/O关系，而改变与MN类型相关的功能分布。改变重复性抑制的整体增益，就像在各种运动行为中自然发生的那样，改变了I/O关系的斜率和位置(在高输入时)，使重复性抑制成为一种合适的增益控制手段。在慢的动态收缩过程中，反复抑制增益的减少与dcs输入的增加结合在一起，将增加动作过程中的MN和力量增益。短的动态斜坡和保持的分布式控制系统输入产生MN的放电模式，在这种模式下，反复的抑制导致了与震颤及其控制问题有关的尖峰间期变异性和阻尼性振荡。
Abstract.The physiological function of spinal recurrent inhibition is still a matter of debate because of the experimental difficulty or impossibility of observing recurrent inhibition at work in normally behaving animals. The purpose of this study was to investigate, by computer simulation, the role of recurrent inhibition in shaping the input-output (I/O) relationships between descending command signals (DCS) as inputs and motoneuron (MN) and Renshaw cell (RC) firing rates and muscle force as outputs. Changing the spatial (topographical) distribution of recurrent inhibition from nonhomogeneous (as in the standard model) to homogeneous did not alter the I/O relationships significantly, while changing the functional distribution related to MN types did. Altering the global gain of recurrent inhibition, as happens naturally in various motor acts, changes the slopes and positions (at high inputs) of the I/O relationships, making recurrent inhibition a suitable means of gain control. Coupling a decrease in recurrent inhibitory gain with an increase in DCS input, as could occur during slow dynamic contractions, would increase the MN and force gains during the act. Short dynamic ramp-and-hold DCS inputs generate MN firing patterns, to which recurrent inhibition contributes interspike-interval variability and damped oscillations, which are related to issues of tremor and its control.
猫个体运动神经元之间反复抑制突触后电位的地形图。
影响因子：
2.5
作者：
McCurdy,ML;Hamm,TM
通讯作者：
Hamm,TM
影响因子：
2.5
作者：
FYFFE, REW
通讯作者：
FYFFE, REW
影响因子：
2.5
作者：
Maltenfort, MG;Heckman, CJ;Rymer, WZ
通讯作者：
Rymer, WZ