Finger and face representations in the ipsilateral precentral motor areas in humans
Finger and face representations in the ipsilateral precentral motor areas in humans
复制标题
DOI：
10.1152/jn.00784.2004
复制
发表时间：
2005-05-01
影响因子：
2.5
通讯作者：
Hallett, M
中科院分区：
文献类型：
--
作者：
Hanakawa, T;Parikh, S;Hallett, M
几项人类神经影像学研究报告了手部运动同侧的中央前回（PcG）的活动。这种活动被解释为控制双侧或同侧手部运动的初级运动皮层（M1）的一部分。为了更好地了解手同侧-PcG活动，我们进行了功能性MRI实验在8个健康的右利手成年人。行为任务涉及每侧的手或下面部运动或相同运动的运动想象。与已知的M1组织相一致，手对侧PcG活动集中在PcG的“手旋钮”部分;脸对侧PcG活动定位在腹外侧。然而，收敛的结果表明，这同侧PcG活动位于Brodmann的6区在两个半球。手同侧PcG区不仅在手部运动中活跃，而且在面部运动中也活跃。此外，手同侧PcG区显示大量的图像相关活动，这也未能区分手和脸。统计分析证实，在运动和图像任务的手同侧PcG活动的效果差的选择性。从这些结果，我们得出结论，在健康成人的手同侧-PcG活动可能对应于腹侧前运动皮层的一部分。相反，现有证据表明，M1有助于控制儿童和中风恢复后患者的同侧手。看来，在人类的PcG，有两个平行的系统可能能够控制同侧的手的运动：腹侧运动前皮质和M1。这两个系统可能受到发育或病理变化的不同影响。
Several human neuroimaging studies have reported activity in the precentral gyrus (PcG) ipsilateral to the side of hand movements. This activity has been interpreted as the part of the primary motor cortex (M1) that controls bilateral or ipsilateral hand movements. To better understand hand ipsilateral-PcG activity, we performed a functional MRI experiment in eight healthy right-handed adults. Behavioral tasks involved hand or lower face movements on each side or motor imagery of the same movements. Consistent with the known M1 organization, the hand contralateral-PcG activity was centered at the "hand-knob" portion of the PcG; face contralateral-PcG activity was localized ventrolateral to it. Hand ipsilateral-PcG activity was identified in most subjects. However, converging results indicated that this ipsilateral PcG activity was situated in Brodmann's area 6 in both hemispheres. The hand ipsilateral-PcG zones were active not only during hand movements but also face movements. Moreover, the hand ipsilateral-PcG zones revealed substantial imagery-related activity, which also failed to differentiate the hand and face. Statistical analyses confirmed poor effector selectivity of the hand ipsilateral PcG activity during both movement and imagery tasks. From these results, we conclude that the hand ipsilateral-PcG activity in healthy adults probably corresponds to a part of the ventral premotor cortex. In contrast, available evidence suggests that M1 contributes to controlling the ipsilateral hand in children and patients after stroke recovery. It appears that within the human PcG, there are two parallel systems potentially capable of controlling ipsilateral hand movements: ventral premotor cortex and M1. These two systems may be differentially influenced by developmental or pathologic changes.