Ofori Edward, Coombes Stephen A, Vaillancourt David E
Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA.
Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA; Department of Neurology, University of Florida, Gainesville, FL 32611, USA.
Neuroimage. 2015 Jul 15;115:30-41. doi: 10.1016/j.neuroimage.2015.04.043. Epub 2015 Apr 27.
Precise motor control requires the ability to scale the parameters of movement. Theta oscillations across the cortex have been associated with changes in memory, attention, and sensorimotor processing. What has proven more elusive is pinpointing the region-specific frequency band oscillations that are associated with specific parameters of movement during the acceleration and deceleration phases. We report a study using 3D analytic techniques for high density electroencephalography that examines electrocortical dynamics while participants produce upper limb movements to different distances at varying rates. During fast ballistic movements, we observed increased theta band activity in the left motor area contralateral to the moving limb during the acceleration phase of the movement, and theta power correlated with the acceleration of movement. In contrast, beta band activity scaled with the type of movement during the deceleration phase near the end of the movement and correlated with movement time. In the ipsilateral motor and somatosensory area, alpha band activity decreased with the type of movement near the end of the movement, and gamma band activity in visual cortex increased with the type of movement near the end of the movement. Our results suggest that humans use distinct lateralized cortical activity for distance and speed dependent arm movements. We provide new evidence that a temporary increase in theta band power relates to movement acceleration and is important during movement execution. Further, the theta power increase is coupled with desychronization of beta band power and alpha band power which are modulated by the task near the end of movement.
精确的运动控制需要具备调整运动参数的能力。整个皮层的θ振荡与记忆、注意力和感觉运动处理的变化有关。然而，更难以捉摸的是确定在加速和减速阶段与特定运动参数相关的区域特异性频段振荡。我们报告了一项使用高密度脑电图的3D分析技术的研究，该研究在参与者以不同速度将上肢移动到不同距离时检查皮层电动力学。在快速弹道运动中，我们观察到在运动的加速阶段，与运动肢体对侧的左运动区域的θ频段活动增加，并且θ功率与运动加速度相关。相比之下，在运动接近尾声的减速阶段，β频段活动随运动类型而变化，并与运动时间相关。在同侧运动和体感区域，α频段活动在运动接近尾声时随运动类型而降低，而视觉皮层中的γ频段活动在运动接近尾声时随运动类型而增加。我们的结果表明，人类在进行与距离和速度相关的手臂运动时使用不同的偏侧化皮层活动。我们提供了新的证据，表明θ频段功率的暂时增加与运动加速度有关，并且在运动执行过程中很重要。此外，θ功率的增加与β频段功率和α频段功率的去同步化相关，而β频段功率和α频段功率在运动接近尾声时受任务调制。
