Department of Physiology and Biophysics, School of Medicine, University of Buenos Aires, C1121ABG Buenos Aires, Argentina.
J Neurosci. 2011 Aug 17;31(33):11808-13. doi: 10.1523/JNEUROSCI.2253-11.2011.
The neural bases of motor adaptation have been extensively explored in human and nonhuman primates. A network including the cerebellum, primary motor cortex, and posterior parietal cortex appears to be crucial for this type of learning. Yet, to date, it is unclear whether these regions contribute directly or indirectly to the formation of motor memories. Here we trained subjects on a complex visuomotor rotation associated with long-term memory (in the order of months) to identify potential sites of structural plasticity induced by adaptation. One week of training led to (1) an increment in local gray matter concentration over the hand area of the contralateral primary motor cortex and (2) an increase in fractional anisotropy in an area underneath this region that correlated with the speed of learning. Moreover, the change in gray matter concentration measured immediately after training predicted improvements in the speed of learning during readaptation 1 year later. Our study suggests that motor adaptation induces structural plasticity in primary motor circuits. In addition, it provides the first piece of evidence indicating that early structural changes induced by motor learning may impact on behavior up to 1 year after training.
运动适应的神经基础在人类和非人类灵长类动物中得到了广泛的研究。一个包括小脑、初级运动皮层和顶后皮质的网络似乎对这种类型的学习至关重要。然而，迄今为止，尚不清楚这些区域是直接还是间接地促成了运动记忆的形成。在这里，我们对与长期记忆（数月）相关的复杂视觉运动旋转进行了训练，以确定适应引起的结构可塑性的潜在部位。一周的训练导致（1）对侧初级运动皮层手部区域的局部灰质浓度增加，以及（2）该区域下方的各向异性分数增加，与学习速度相关。此外，训练后立即测量的灰质浓度变化可预测 1 年后重新适应时学习速度的提高。我们的研究表明，运动适应会引起初级运动回路的结构可塑性。此外，它提供了第一个证据，表明运动学习引起的早期结构变化可能会在训练后长达 1 年的时间内影响行为。
