An fMRI study of brain activation in a visual adaptation task: activation limited to sensory guidance
An fMRI study of brain activation in a visual adaptation task: activation limited to sensory guidance
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DOI：
10.1007/s00221-007-1124-8
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发表时间：
2008-02-01
影响因子：
2
通讯作者：
Seitz, Ruediger J.
中科院分区：
文献类型：
--
作者：
Girgenrath, Michaela;Bock, Otmar;Seitz, Ruediger J.
以前的神经成像研究发现，在感觉运动适应过程中，当引入感觉冲突时，例如通过操纵视觉信息，大脑区域会激活不同的模式。我们认为，可能的原因可能是缺乏对适应的控制或运动表现的变化。因此，无法区分与适应相关的和与错误相关的大脑活动。我们开发了一种感觉-运动适应任务，它使用两种类型的视觉失真来控制这些错误，因此适合于从相关的激活模式中消除感觉-运动适应的歧义。20名健康受试者在一项跟踪任务中进行了fMRI扫描，同时适应了取决于手部位置或手部速度的视觉失真。在任何一种情况下，自适应都与控制条件交织在一起，控制条件的设计使跟踪误差的时间进程接近于视觉失真下的时间进程。我们发现，在位置依赖扭曲下，适应相关神经活动仅限于左侧缘上回和角回，而在速度依赖扭曲下，双侧缘上回以及左侧中、右额上回均被激活。我们的发现证实，与其他研究相比，将这两种情况下的错误等同起来，将产生解剖学上更受限的激活模式。在速度依赖的扭曲下，右侧顶叶和双侧额区的额外招募可能反映了更高的计算需求，或参与了不同的适应机制。
Previous neuroimaging studies yielded different patterns of brain areas activated during sensorimotor adaptation, when sensory conflicts are introduced, e.g. by manipulating visual information. We propose that possible reasons might be the lack to control for adaptation or the change in motor performance. In consequence, it was not possible to distinguish between adaptation-related and error-related brain activations. We have developed a sensorimotor adaptation task which controls for these errors using two types of visual distortion and thus is suited to disambiguate sensorimotor adaptation from the related activation patterns. Twenty healthy subjects were scanned by fMRI during a tracking task, while adapting to a visual distortion, which depended either on hand position or on hand velocity. In either case, adaptation was interleaved with a control condition, designed such that the time-course of tracking errors approximated that under visual distortion. We found that adaptation-related neural activation was limited to the left supramarginal and angular gyrus under the position-dependent distortion, but extended bilaterally in the supramarginal gyrus, as well as in the left middle and right superior frontal gyrus under the velocity-dependent distortion. Our findings confirm that equating the errors under both conditions will yield an anatomically more restricted activation pattern compared with other studies. The additional recruitment in right parietal and bilateral frontal areas under the velocity-dependent distortion might reflect a higher computational demand, or the involvement of different adaptive mechanisms.