Kristeva-Feige Rumyana, Fritsch Christoph, Timmer Jens, Lücking Carl-Hermann
Neurological Clinic, Albert-Ludwigs-University, Breisacherstrasse 64, 79106 Freiburg, Germany.
Clin Neurophysiol. 2002 Jan;113(1):124-31. doi: 10.1016/s1388-2457(01)00722-2.
The present study was aimed at investigating the effect of attention and precision level of exerted force on beta range EEG-EMG synchronization.
We simultaneously recorded cortical electrical activity (EEG) in a bipolar manner from the contralateral sensorimotor areas and surface electromyographic (EMG) activity from the flexor digitorum superficialis muscle in 10 healthy subjects during a maintained motor contraction task at 8% of the maximal voluntary contraction (MVC) force level. The coherence between oscillatory processes in the EEG and EMG was calculated. Three different conditions were investigated: (i) performing the task with high precision (HP); (ii) performing the task with high precision and simultaneously performing a mental arithmetic task (HPAT), i.e. attention was divided between the motor task and the mental arithmetic task; and (iii) performing the task with low precision (LP).
We have found that the amount of beta range EEG-EMG synchronization decreases below the 95% confidence level when attention is divided between the motor task and the mental arithmetic task. The results also show that the frequency of beta range synchronization is higher with a higher level of precision but still lies within the beta frequency range (15-30 Hz).
The data indicate that beta range synchronization represents a state of the cortico-muscular network when attention is directed towards the motor task. The frequency of synchronization of this network is associated with, and possibly encodes, precision in force production.
本研究旨在探究注意力和用力精准度水平对β频段脑电图-肌电图同步性的影响。
我们以双极方式同步记录了10名健康受试者在以最大自主收缩（MVC）力水平的8%进行持续运动收缩任务期间，对侧感觉运动区的皮质电活动（脑电图）和指浅屈肌的表面肌电图（肌电图）活动。计算脑电图和肌电图振荡过程之间的相干性。研究了三种不同情况：（i）高精度执行任务（HP）；（ii）高精度执行任务并同时执行心算任务（HPAT），即注意力在运动任务和心算任务之间分配；以及（iii）低精度执行任务（LP）。
我们发现，当注意力在运动任务和心算任务之间分配时，β频段脑电图-肌电图同步量下降至95%置信水平以下。结果还表明，β频段同步频率在精度水平较高时更高，但仍处于β频率范围内（15 - 30赫兹）。
数据表明，当注意力指向运动任务时，β频段同步代表了皮质-肌肉网络的一种状态。该网络的同步频率与力产生的精度相关，并且可能对其进行编码。
