McGill University, Montreal, Quebec H3A 1B1, Canada, Functional Neuroimaging Unit, University of Montreal, Quebec H3W 1W5, Canada, and Haskins Laboratories, New Haven, Connecticut 06511.
J Neurosci. 2014 Feb 12;34(7):2451-63. doi: 10.1523/JNEUROSCI.4291-13.2014.
As we begin to acquire a new motor skill, we face the dual challenge of determining and refining the somatosensory goals of our movements and establishing the best motor commands to achieve our ends. The two typically proceed in parallel, and accordingly it is unclear how much of skill acquisition is a reflection of changes in sensory systems and how much reflects changes in the brain's motor areas. Here we have intentionally separated perceptual and motor learning in time so that we can assess functional changes to human sensory and motor networks as a result of perceptual learning. Our subjects underwent fMRI scans of the resting brain before and after a somatosensory discrimination task. We identified changes in functional connectivity that were due to the effects of perceptual learning on movement. For this purpose, we used a neural model of the transmission of sensory signals from perceptual decision making through to motor action. We used this model in combination with a partial correlation technique to parcel out those changes in connectivity observed in motor systems that could be attributed to activity in sensory brain regions. We found that, after removing effects that are linearly correlated with somatosensory activity, perceptual learning results in changes to frontal motor areas that are related to the effects of this training on motor behavior and learning. This suggests that perceptual learning produces changes to frontal motor areas of the brain and may thus contribute directly to motor learning.
当我们开始掌握一项新的运动技能时，我们面临着双重挑战，既要确定和完善运动的感觉目标，又要建立实现目标的最佳运动指令。这两者通常是并行的，因此，不清楚技能习得的多少是感觉系统变化的反映，多少是大脑运动区域变化的反映。在这里，我们有意在时间上分开感知和运动学习，以便我们可以评估感知学习对人类感觉和运动网络的功能变化。我们的受试者在进行躯体感觉辨别任务之前和之后接受了静息态 fMRI 扫描。我们确定了由于感知学习对运动的影响而导致的功能连接变化。为此，我们使用了从感知决策到运动动作的感觉信号传输的神经模型。我们将该模型与部分相关技术结合使用，将在运动系统中观察到的那些可以归因于感觉脑区活动的连接变化分开。我们发现，在去除与躯体感觉活动线性相关的影响后，感知学习导致与该训练对运动行为和学习的影响相关的额叶运动区域的变化。这表明感知学习会导致大脑额叶运动区域的变化，从而可能直接促进运动学习。
