Motor cortical activity during voluntary gait modifications in the cat. I. Cells related to the forelimbs.
Motor cortical activity during voluntary gait modifications in the cat. I. Cells related to the forelimbs.
复制标题
猫自愿步态改变期间的运动皮质活动。
DOI：
10.1152/jn.1994.72.5.2070
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发表时间：
1993
影响因子：
2.5
通讯作者：
T. Drew
中科院分区：
文献类型：
--
作者：
T. Drew
1. 91个确定的锥体束神经元（PTNs），位于猫运动皮层4区的前肢区域内的放电模式，记录在自愿修改的步态需要跨越障碍物连接到一个移动的跑步机带。记录同时从屈肌和伸肌周围的肩膀，肘部，手腕，和数字的前肢对侧的记录网站。2.在步态修改过程中的肌电图（EMG）活动的变化分析表明，增加的活动，大多数屈肌的肩膀和肘部，以及在手腕和手指背屈肌，当对侧前肢是第一个通过的障碍。这一阶段的增强活动可以细分为两个部分：一个与肢体的初始屈曲相关，需要将其带到障碍物上方（I期），第二个与足部接触前腕背屈肌活动增加相关（II期）。3.当记录部位对侧的肢体第一个跨过障碍物时，在步态修改过程中，总共57/91（63%）记录的PTNs的放电频率显著增加;其中6个神经元在步骤周期的不同部分中的放电也显著减少。在另外21/91（23%）的神经元中，放电频率仅降低，而其余13/91（14%）的PTNs在控制行走和步态修改期间显示出类似的活动模式。4.大多数神经元（47/57），其中观察到的放电频率显着增加，最大放电期间的生理屈肌活动增加。这些细胞中的23个（23/47）在I相最大放电，12个（12/47）在II相最大放电。第三组PTNS（12/47）在改良周期前的步行周期的站立阶段开始增加其放电。七（7/57）PTNs增加了他们的放电在修改周期的立场阶段，其余三个不能被归类为优先相关的任何一个部分的步骤周期。5.当记录部位对侧的腿是第二个遇到障碍物时，41/57个PTNs的频率调制较小。在许多神经元也有一个明显的变化，在时间的步骤周期，峰值放电发生。这些幅度和时间上的变化与在肌肉的时间关系中观察到的变化一致。（400字处截断摘要）
1. The discharge patterns of 91 identified pyramidal tract neurons (PTNs), located within the forelimb region of area 4 of the cat motor cortex, were recorded during the voluntary modifications of gait needed to step over obstacles attached to a moving treadmill belt. Recordings were made simultaneously from flexor and extensor muscles acting around the shoulder, elbow, wrist, and digits of the forelimb contralateral to the recording site. 2. Analysis of the changes in electromyographic (EMG) activity during the gait modification showed increases in the activity of most flexor muscles of the shoulder and elbow, as well as in the wrist and digit dorsiflexors, when the contralateral forelimb was the first to pass over the obstacle. This period of augmented activity could be subdivided into two parts: one associated with the initial flexion of the limb that was needed to bring it above and over the obstacle (phase I), and the second associated with increased wrist dorsiflexor muscle activity before foot contact (phase II). 3. The discharge frequency of a total of 57/91 (63%) of the recorded PTNs was significantly increased during the gait modification when the limb contralateral to the recording site was the first to step over the obstacle; six of these neurons also showed a significant decrease in their discharge in a different part of the step cycle. In a further 21/91 (23%) neurons, discharge frequency was only decreased, whereas the remaining 13/91 (14%) PTNs showed similar patterns of activity both during control walking and during the gait modifications. 4. Most of those neurons (47/57) in which significant increases in firing frequency were observed, discharged maximally during the period of increased activity of the physiological flexor muscles. Twenty-three of these cells (23/47) discharged maximally in phase I, and 12 (12/47) in phase II. A third population of PTNS (12/47) started to increase their discharge in the stance phase of the step cycle immediately preceding the modified cycle. Seven (7/57) PTNs increased their discharge during the stance phase of the modified cycle, and the remaining three could not be classified as being preferentially related to any one part of the step cycle. 5. The frequency modulation of 41/57 PTNs was less when the leg contralateral to the recording site was the second to encounter the obstacle. In many neurons there was also an appreciable change in the time in the step cycle that peak discharge occurred. These changes in amplitude and timing paralleled the changes observed in the temporal relationships of the muscles.(ABSTRACT TRUNCATED AT 400 WORDS)