Stumbling corrective reaction: a phase-dependent compensatory reaction during locomotion.
Stumbling corrective reaction: a phase-dependent compensatory reaction during locomotion.
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绊倒校正反应：运动过程中依赖于相位的补偿反应。
DOI：
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发表时间：
1979
影响因子：
2.5
通讯作者：
H. Forssberg
中科院分区：
文献类型：
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作者：
H. Forssberg
1.用触觉刺激的方法研究了运动活动对猫伸肌和屈肌反射模式和代偿性运动的时相影响。由此产生的动作和反射模式被称为“跌倒矫正反应”。2.绊倒矫正反应的基本反射模式和动作是：a)如果刺激发生在摆动阶段，屈肌的短潜伏期激活，这导致肢体额外屈曲，将爪子抬过障碍物；b)如果刺激发生在支撑阶段，抑制之后是伸肌的兴奋，这既不会增加也不会减少伸展。然而，在随后的摆动阶段，刺激会引起屈肌活动增加，从而导致更快的屈曲。3.对肢体近端或膝前腹部的触觉刺激可引起相同类型的相依性代偿反应。这样的反应可能有利于动物避开阻碍移动的高空障碍物。4.采用非伤害性电刺激(一般为2 mA，1ms)刺激足掌背侧，系统地研究了跌倒矫正反应的反射模式。膝关节屈肌(半腱肌群)有两条通路。在刺激后约25ms，分别在约10ms和25ms处诱发了一次早期的猝发。短抑制性通路和长兴奋性通路(20-50ms)投射到伸肌核团。短潜伏期(10ms)至踝伸肌群(外侧腓肠肌)的兴奋通路也被激活。5.在整个台阶周期中，对爪背施加痛苦的电刺激可引起大的屈肌反应。在支撑阶段，由于支撑肢被收回，运动被打断。6.结果表明，完整的猫能够迅速补偿意外的干扰，反射模式和诱导的纠正性动作与运动活动相适应，从而在踏步周期的每个阶段都能诱发出有功能意义的动作。7.诱发的反射和它们的调制与先前在慢性脊髓猫行走时和在瘫痪的脊髓猫进行“假想运动”时发现的一致。有人建议使用相同的脊椎通路，并由脊椎“运动发生器”控制它们。
1. Tactile stimuli to the paw consisting of a stick making contact or an air puff aimed at the dorsum were used to study the phasic influence of locomotor activity on the reflex pattern elicited in extensor and flexor muscles and on the induced compensatory movements in intact cats. The resulting movements and reflex pattern are called "stumbling corrective reactions." 2. The basic reflex pattern and movements of the stumbling corrective reaction are: a) if the stimulus occurs during the swing phase, a short-latency activation of the flexor muscles, which induces an additional flexion of the limb lifting the paw over the obstacle; b) if the stimulus occurs during the support phase, an inhibition followed by an excitation of the extensor muscles, which neither increase nor decrease the extension. However, the stimulus evokes an increased flexor activity in the succeeding swing phase, which induces a brisker flexion. 3. Tactile stimuli to the proximal part of the limb or to the belly in front of the knee evoked the same type of phase-dependent compensatory reactions. Such reactions would presumably be beneficial for the animal to avoid high obstacles that impede movement. 4. A nonnoxious electrical stimulus (typically 2 mA; 1 ms) applied to the dorsum of the paw was used to study systematically the reflex pattern of the stumbling corrective reaction. Two pathways were defined to the knee flexor (semitendinosus). One early burst was evoked at about 10 ms and one later at about 25 ms after the stimulus. Short inhibitory pathways and longer excitatory pathways (20-50 ms) projected to the extensor nuclei. A short-latency (10 ms) excitatory pathway to the ankle extensor (lateral gastrocnemius) was also activated. 5. A painful electrical stimulus applied to the dorsum of the paw evoked large flexor responses during the whole step cycle. During the support phase the locomotion was disrupted as the supporting limb was withdrawn. 6. The results demonstrate that intact cats are able to compensate rapidly for unpredicted perturbations and that the reflex pattern and the induced corrective movements are adapted to the locomotor activity so that functionally meaningful movements are evoked in each phase of the step cycle. 7. The evoked reflexes and their modulation are consistent with those previously found in chronic spinal cats during walking and in paralyzed spinal cats performing "fictive locomotion." It is suggested that the same spinal pathways are used, and that they are controlled by the spinal "locomotor generator."