Terada K, Ikeda A, Nagamine T, Shibasaki H
Department of Brain Pathophysiology, Kyoto University School of Medicine, Japan.
Electroencephalogr Clin Neurophysiol. 1995 Nov;95(5):335-45. doi: 10.1016/0013-4694(95)00098-j.
We recorded movement-related cortical potentials (MRCPs) associated with voluntary muscle relaxation, which was not accompanied by contraction of the antagonist or any other muscles, in 10 normal subjects. Voluntary, self-paced relaxation of the wrist extensors from the extended position was employed as the relaxation task, and wrist flexion by muscle contraction was employed as the contraction task. The accelerogram was used to obtain the trigger signals for both tasks. The electromyograms of the ipsilateral agonist and antagonist, the proximal muscles and the contralateral corresponding muscles were monitored to confirm the absence of muscle contraction for the relaxation task. All MRCP components were identified in both tasks; Bereitschaftspotential (BP), negative slope (NS'), parietal peak of motor potential (ppMP) and frontal peak of motor potential (fpMP). BP started earlier and was larger at the contralateral parietotemporal electrodes for the relaxation than for the contraction task, and the slow positive shift at the bilateral frontopolar electrodes was seen more often in the relaxation task. It is concluded that the voluntary muscle relaxation needs a cortical preparatory process similar to voluntary muscle contraction, and needs a more extensive and longer preparation process in the primary motor area and possibly in other motor areas as compared with the contraction.
我们记录了10名正常受试者与随意肌肉放松相关的运动相关皮层电位（MRCPs），这种放松未伴有拮抗肌或任何其他肌肉的收缩。将从伸展位置开始的腕伸肌的随意、自定节奏的放松作为放松任务，将通过肌肉收缩进行的腕屈曲作为收缩任务。加速度图用于获取两项任务的触发信号。监测同侧主动肌和拮抗肌、近端肌肉以及对侧相应肌肉的肌电图，以确认放松任务时无肌肉收缩。在两项任务中均识别出所有MRCP成分； Bereitschaft电位（BP）、负斜率（NS'）、运动电位顶叶峰（ppMP）和运动电位额叶峰（fpMP）。与收缩任务相比，放松任务时BP在对侧顶颞电极处起始更早且更大，并且双侧额极电极处的缓慢正移在放松任务中更常出现。结论是，随意肌肉放松需要一个类似于随意肌肉收缩的皮层准备过程，并且与收缩相比，在初级运动区以及可能在其他运动区需要更广泛和更长的准备过程。
