The absence of position response in spindle afferent units from human finger muscles during accurate position holding.
The absence of position response in spindle afferent units from human finger muscles during accurate position holding.
复制标题
在准确的位置保持过程中，人类手指肌肉的纺锤体传入单位缺乏位置响应。
DOI：
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发表时间：
1982
期刊：
影响因子：
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通讯作者：
Å. Vallbo
中科院分区：
文献类型：
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作者：
M. Hulliger;E. Nordh;Å. Vallbo
1.在清醒受试者的桡神经上记录到伸指肌肌梭传入的单一单位活动。将受体相关的手指固定在掌指关节的固定角度位置，测定传入单位的平均放电频率。2.在视觉跟踪任务中，受试者必须保持特定的角度位置，以对抗不利于手指伸展的恒定扭矩负荷。对于每个单元，在相差20度的两个角度位置的平均放电速率之间进行了比较。在这种等渗条件下，两个关节位置的传入放电速率没有显著差异，无论是初级样本的整个样本，还是次级单位的样本。这是正确的，无论负荷是小的还是中等的。没有对大负荷进行测试。3.为了比较，研究了同一肌肉的纺锤形传入单位样本在手指处于固定位置时，肌肉主动放松时的被动位置反应。在这些条件下，初级和次级传入都有显着的位置敏感性。平均值为0.28个脉冲/秒。Deg(初级脉冲)和0.21脉冲/秒。DEG(中学)。4.主动姿势保持时没有位置反应被解释为梭形运动流出的变化的一种表现，这种变化取决于关节的位置，其大小足以补偿肌肉长度的变化。
1. Single unit activity of muscle spindle afferents from finger extensor muscles was recorded in the radial nerve of waking human subjects. The mean discharge rate of the afferent units was determined while the receptor related finger was held at fixed angular positions of the metacarpo‐phalangeal joint. 2. During a visual tracking task the subjects had to maintain specified angular positions against a load of constant torque which opposed finger extension. For each unit a comparison was made between the mean discharge rates at two angular positions which differed by 20 deg. Under such isotonic conditions the rates of afferent discharge at the two joint positions did not significantly differ, neither for the whole sample of primary, nor for that of secondary units. This was true, no matter whether the load was small or intermediate. Large loads were not tested. 3. For comparison, the passive position responses of a sample of spindle afferent units from the same muscles were studied when the finger was held in fixed positions while the muscles were voluntarily relaxed. Under these conditions a significant position sensitivity was found for both primary and secondary afferents. The mean values were 0.28 impulses/sec. deg (primaries), and 0.21 impulses/sec. deg (secondaries). 4. The absence of position response during active position holding was interpreted as a manifestation of changes in fusimotor outflow which depended on joint position and were large enough to compensate for changes in muscle length.