Coherent oscillations in monkey motor cortex and hand muscle EMG show task-dependent modulation
Coherent oscillations in monkey motor cortex and hand muscle EMG show task-dependent modulation
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DOI：
10.1111/j.1469-7793.1997.225bo.x
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发表时间：
1997-05-15
影响因子：
5.5
通讯作者：
Lemon, RN
中科院分区：
文献类型：
--
作者：
Baker, SN;Olivier, E;Lemon, RN
1.记录了局部场电位（慢波）和锥体束神经元（PTN）放电对的网站分开的水平距离达1.5毫米，在两个清醒的猕猴执行精确的抓任务的初级运动皮层。在这两只猴子中，慢波记录显示在20-30 Hz范围内的振荡爆发。频谱分析表明，振荡仅仅是相干的两个同时记录的皮层网站之间。在记录大部分数据的猴子中，峰值相干性的平均频率为23.4 Hz。在这个频率范围内的一致性也被认为是皮质慢波记录和整流EMG的手和前臂肌肉活动在任务期间，和对整流EMG之间。通过分析短的，准静态的数据段对齐相对于任务性能的一致性的动态进行了研究。这揭示了20-30 Hz的相干振荡主要存在于精确抓握任务的保持阶段。识别出的PTNs的尖峰被用于编译慢波记录的尖峰触发的平均值。在与触发尖峰相同的电极上记录的慢波的11/17平均值和在远距离电极上记录的慢波的11/17平均值中观察到振荡。这些振荡的平均周期为45.8毫秒。它的结论是，在20-30 Hz的范围内的振荡是存在于猴子的运动皮层，空间分离的皮层网站之间的连贯性，并包括锥体束输出神经元。它们在活动肌肉的EMG中是可辨别的，并且显示出一致的任务依赖性调制。
1. Recordings were made of local field potential (slow waves) and pyramidal tract neurone (PTN) discharge from pairs of sites separated by a horizontal distance of up to 1.5 mm in the primary motor cortex of two conscious macaque monkeys performing a precision grip task.2. In both monkeys, the slow wave recordings showed bursts of oscillations in the 20-30 Hz range. Spectral analysis revealed that the oscillations mere coherent between the two simultaneously recorded cortical sites. In the monkey from which most data were recorded, the mean frequency of peak coherence was 23.4 Hz.3. Coherence in this frequency range was also seen between cortical slow wave recordings and rectified EMG of hand and forearm muscles active during the task, and between pairs of rectified EMGs.4. The dynamics of the coherence were investigated by analysing short, quasi-stationary data segments aligned relative to task performance. This revealed that the 20-30 Hz coherent oscillations were present mainly during the hold phase of the precision grip task.5. The spikes of identified PTNs were used to compile spike-triggered averages of the slow wave recordings. Oscillations were seen in 11/17 averages of the slow wave recorded on the same electrode as the triggering spike, and 11/17 averages of the slow wave recorded on the distant electrode. The mean period of these oscillations was 45.8 ms.6. It is concluded that oscillations in the range 20-30 Hz are present in monkey motor cortex, are coherent between spatially separated cortical sites, and encompass the pyramidal tract output neurones. They are discernable in the EMG of active muscles, and show a consistent task-dependent modulation.