Gorbet Diana J, Staines W Richard, Sergio Lauren E
School of Kinesiology and Health Science, York University, 4700 Keele Street Toronto, Ontario, Canada M3J 1P3.
Neuroimage. 2004 Nov;23(3):1100-11. doi: 10.1016/j.neuroimage.2004.07.043.
Movements made in response to sensory cues require the brain to transform sensory information into an appropriate motor output. Sensorimotor mappings used in daily life range from direct or "standard" to highly complex. In "nonstandard" sensorimotor tasks, the visual stimulus guiding an action is often not the target of the action. A common example of such a nonstandard mapping is the use of a computer mouse on a horizontal surface to guide an object visible on a vertical monitor. The present study used event-related BOLD fMRI to examine how patterns of brain activity vary as sensorimotor mappings become progressively more complicated. We observed significantly different patterns of cortical activity depending on the level of dissociation between a sensory input and a required motor response. Our results suggest the presence of a functional network generally involved in performing the type of nonstandard sensorimotor tasks examined. This putative network includes regions of the primary motor cortex, medial motor areas, the superior parietal lobule (SPL), and the lateral premotor cortex. The extent of activity in active areas varied depending on the characteristics of the particular sensorimotor mapping used in performing a task. Furthermore, in addition to this putative network, specific task-related areas of activity were observed.
对感觉线索做出的动作需要大脑将感觉信息转化为适当的运动输出。日常生活中使用的感觉运动映射范围从直接或“标准”到高度复杂。在“非标准”感觉运动任务中，引导动作的视觉刺激通常不是动作的目标。这种非标准映射的一个常见例子是在水平表面上使用电脑鼠标来引导垂直显示器上可见的物体。本研究使用事件相关的BOLD功能磁共振成像来检查随着感觉运动映射变得越来越复杂，大脑活动模式是如何变化的。我们观察到，根据感觉输入和所需运动反应之间的分离程度，皮质活动模式存在显著差异。我们的结果表明存在一个通常参与执行所研究的非标准感觉运动任务类型的功能网络。这个假定的网络包括初级运动皮层、内侧运动区、顶上小叶（SPL）和外侧运动前皮层区域。活跃区域的活动程度根据执行任务时使用的特定感觉运动映射的特征而有所不同。此外，除了这个假定的网络外，还观察到了特定的任务相关活动区域。
