Motor Planning, Imagery, and Execution in the Distributed Motor Network: A Time-Course Study with Functional MRI
Motor Planning, Imagery, and Execution in the Distributed Motor Network: A Time-Course Study with Functional MRI
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DOI：
10.1093/cercor/bhn036
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发表时间：
2008-12-01
期刊：
影响因子：
3.7
通讯作者：
Hallett, Mark
中科院分区：
文献类型：
--
作者：
Hanakawa, Takashi;Dimyan, Michael A.;Hallett, Mark
运动相关区域的激活一直存在于各种运动表象任务中，并被认为是产生运动表象的中心机制。然而，运动执行和想象在多大程度上共享神经底物仍然存在争议。我们检查了身体或精神手指敲击的准备和执行过程中的大脑活动。在3T的功能性磁共振成像期间，13名健康志愿者在身体模式或心理模式下执行了一项指令延迟的手指敲击任务。数字刺激指示受试者手指敲击的顺序。在一段指示的延迟期后，提示刺激促使他们要么执行敲击动作，要么想象它。运动和想象的两种常见的计划/准备活动被发现：指令刺激相关活动广泛存在于多个运动相关区域和延迟期活动在额叶内侧区域。虽然运动执行中的大脑活动和想象在分布式运动网络中大部分是共享的，但一般而言，想象相关活动与指令相关活动的关系比与运动执行相关的活动更密切。具体地说，内侧额上回、前扣带回、中央前沟、缘上回、梭状回和小脑后外侧的活动可能反映了对虚拟运动指令的有意产生和对虚拟感觉信号的分析。
Activation of motor-related areas has consistently been found during various motor imagery tasks and is regarded as the central mechanism generating motor imagery. However, the extent to which motor execution and imagery share neural substrates remains controversial. We examined brain activity during preparation for and execution of physical or mental finger tapping. During a functional magnetic resonance imaging at 3 T, 13 healthy volunteers performed an instructed delay finger-tapping task either in a physical mode or mental mode. Number stimuli instructed subjects about a finger-tapping sequence. After an instructed delay period, cue stimuli prompted them either to execute the tapping movement or to imagine it. Two types of planning/preparatory activity common for movement and imagery were found: instruction stimulus-related activity represented widely in multiple motor-related areas and delay period activity in the medial frontal areas. Although brain activity during movement execution and imagery was largely shared in the distributed motor network, imagery-related activity was in general more closely related to instruction-related activity than to the motor execution-related activity. Specifically, activity in the medial superior frontal gyrus, anterior cingulate cortex, precentral sulcus, supramarginal gyrus, fusiform gyrus, and posterolateral cerebellum likely reflects willed generation of virtual motor commands and analysis of virtual sensory signals.