Cunnington Ross, Windischberger Christian, Moser Ewald
The Howard Florey Institute, Centre for Neuroscience, University of Melbourne, Victoria 3010, Australia, and Department of Radiodiagnostics, General Hospital of Vienna, Austria.
Hum Mov Sci. 2005 Oct-Dec;24(5-6):644-56. doi: 10.1016/j.humov.2005.10.001. Epub 2005 Dec 6.
The supplementary motor area (SMA) is thought to play in important role in the preparation and organisation of voluntary movement. It has long been known that cortical activity begins to increase up to 2s prior to voluntary self-initiated movement. This increasing premovement activity measured in EEG is known as the Bereitschaftspotential or readiness potential. Modern functional brain imaging methods, using event-related and time-resolved functional MRI techniques, are beginning to reveal the role of the SMA, and in particular the more anterior pre-SMA, in premovement activity associated with the readiness for action. In this paper we review recent studies using event-related time-resolved fMRI methods to examine the time-course of activation changes within the SMA throughout the preparation, readiness and execution of action. These studies suggest that the pre-SMA plays a common role in encoding or representing actions prior to our own voluntary self-initiated movements, during motor imagery, and from the observation of others' actions. We suggest that the pre-SMA generates and encodes motor representations which are then maintained in readiness for action.
辅助运动区（SMA）被认为在自主运动的准备和组织过程中发挥着重要作用。长期以来，人们已知在自主发起运动前长达2秒，皮层活动就开始增强。脑电图测量到的这种运动前增强活动被称为 Bereitschaftspotential 或准备电位。现代功能性脑成像方法，利用事件相关和时间分辨功能磁共振成像技术，开始揭示辅助运动区，特别是更靠前的前辅助运动区，在与行动准备相关的运动前活动中的作用。在本文中，我们回顾了近期使用事件相关时间分辨功能磁共振成像方法的研究，以考察在整个行动准备、就绪和执行过程中辅助运动区内激活变化的时间进程。这些研究表明，前辅助运动区在我们自主发起运动之前、运动想象期间以及观察他人行动时，在对动作进行编码或表征方面发挥着共同作用。我们认为，前辅助运动区生成并编码运动表征，然后将其保持在准备行动的状态。
