Corrective responses to loss of ground support during walking. I. Intact cats.
Corrective responses to loss of ground support during walking. I. Intact cats.
复制标题
对行走期间失去地面支撑的纠正反应。
DOI：
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发表时间：
1994
影响因子：
2.5
通讯作者：
Michael J. A. Gauthier
中科院分区：
文献类型：
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作者：
M. Gorassini;Arthur Prochazka;G. W. Hiebert;Michael J. A. Gauthier
1. 在猫步循环中，踝伸肌中的肌电图 (EMG) 活动在脚接触之前大约 70 毫秒开始。接触后 10 到 25 毫秒之间出现一个尖锐的峰值，然后肌电图在站立阶段的剩余时间内下降。据推测，接触后肌电图的突然转变是脚触地信号的大量传入输入引起的反射的结果。然而，基本概况也有可能在中枢神经系统内生成，传入输入几乎没有修改。 2. 这些想法在 11 只正常猫身上进行了测试。我们比较了正常地面支撑的步骤中的肌电图反应和后肢运动学，以及执行器控制的活板门意外打开、在脚接触之前撤回地面支撑的步骤。 3. 在没有地面支持的情况下，肌电图活动的转变仍然存在。在脚穿过地板平面后至少 30 毫秒内，平均 EMG 模式是相似的。我们得出的结论是，循环的这一部分中的基本伸肌激活曲线是集中生成的，并且不会因传入输入而发生实质性改变。 4. 接触后 35 到 200 毫秒之间，站立阶段中止，脚被巧妙地从洞中抬起。这种反应在潜伏期和运动学细节上都有所不同，表明纠正反应相当复杂。（摘要截断为 250 字）
1. In the cat step cycle the electromyographic (EMG) activity in ankle extensor muscles commences approximately 70 ms before foot contact. There is a sharp peak between 10 and 25 ms after contact and the EMG then declines for the remainder of the stance phase. It has been posited that the abrupt transition in EMG after contact is the consequence of reflexes elicited by the large barrage of afferent input that signals foot touchdown. However, it is also possible that the basic profile might be generated within the CNS, with little modification by afferent input. 2. These ideas were tested in 11 normal cats. We compared EMG responses and hindlimb kinematics in steps with normal ground support and steps in which an actuator-controlled trap door unexpectedly opened, withdrawing ground support just before foot contact. 3. In the absence of ground support the transition in EMG activity was still present. The averaged EMG pattern was similar for at least 30 ms after the foot passed through the plane of the floor. We conclude that the basic extensor activation profile in this part of the cycle is generated centrally and is not substantially altered by afferent input. 4. Between 35 and 200 ms after contact the stance phase was aborted and the foot was lifted smartly out of the hole. This reaction varied both in latency and kinematic detail, suggesting a fairly complex corrective response.(ABSTRACT TRUNCATED AT 250 WORDS)