Shibuya Kenichi, Kuboyama Naomi
Department of Sports Sciences, Japan Institute of Sports Sciences, 3-15-1 Nishigaoka, Kita-ku, Tokyo, 115-0056, Japan.
Brain Res. 2007 Jul 2;1156:120-4. doi: 10.1016/j.brainres.2007.05.009. Epub 2007 May 10.
There are few observations of the activity of the bilateral motor cortex during prolonged exhaustive motor tasks. Knowing how the motor cortex modulates muscle fatigue or how information about fatigue affects motor cortex activities in healthy humans may help explain why fatigue is so prevalent in patients with neurological disorders. The purpose of the present study was to investigate the time course of oxygenation of the bilateral motor cortex during an exhaustive pinching task. Eight healthy, right-handed subjects participated in the study. Near-infrared spectroscopy over the bilateral motor cortex was used to measure the activity throughout the pinching task. Subjects performed a sustained 50-60% of maximal voluntary contraction until voluntary exhaustion was reached. After the start of the motor task, the contralateral motor cortex oxygenation increased significantly compared with the resting value (P<0.05). However, with the passage of time, it decreased significantly compared with the resting value (P<0.05). In addition, ipsilateral motor cortex oxygenation decreased significantly at voluntary exhaustion compared with the resting value (P<0.05). These results suggest an interaction between the bilateral motor cortices during motor tasks.
关于双侧运动皮层在长时间力竭性运动任务中的活动情况，相关观察较少。了解运动皮层如何调节肌肉疲劳，或者疲劳信息如何影响健康人运动皮层的活动，可能有助于解释为什么疲劳在神经系统疾病患者中如此普遍。本研究的目的是调查在力竭性捏取任务期间双侧运动皮层的氧合时间进程。八名健康的右利手受试者参与了该研究。通过双侧运动皮层上方的近红外光谱法来测量整个捏取任务过程中的活动。受试者进行持续的最大自主收缩的50 - 60%，直到达到自主力竭。运动任务开始后，与静息值相比，对侧运动皮层的氧合显著增加（P<0.05）。然而，随着时间的推移，与静息值相比它显著下降（P<0.05）。此外，在自主力竭时，同侧运动皮层的氧合与静息值相比显著下降（P<0.05）。这些结果表明在运动任务期间双侧运动皮层之间存在相互作用。
