Seidler R D, Noll D C
Division of Kinesiology, Department of Pshychology, University of Michigan, Ann Arbor, Michigan, USA.
J Neurophysiol. 2008 Apr;99(4):1836-45. doi: 10.1152/jn.01187.2007. Epub 2008 Feb 13.
The acquisition of new motor skills is dependent on task practice. In the case of motor transfer, learning can be facilitated by prior practice of a similar skill. Although a multitude of studies have investigated the brain regions contributing to skill acquisition, the neural bases associated with the savings seen at transfer have yet to be determined. In the current study, we used functional MRI to examine how brain activation differs during acquisition and transfer of a visuomotor adaptation task. Two groups of participants adapted manual aiming movements to three different rotations of the feedback display in a sequential fashion, with a return to baseline display conditions between each rotation. Subjects showed a savings in the rate of adaptation when they had prior adaptive experiences (i.e., positive transfer of learning). This savings was associated with a reduction in activity of brain regions typically recruited early in the adaptation process, including the right inferior frontal gyrus, primary motor cortex, inferior temporal gyrus, and the cerebellum (medial HIII). Moreover, although these regions exhibit activation that is correlated across subjects with the rate of acquisition, the degree of savings at transfer was correlated with activity in the right cingulate gyrus, left superior parietal lobule, right inferior parietal lobule, left middle occipital gyrus, and bilaterally in the cerebellum (HV/VI). The cerebellar activation was in the regions surrounding the posterior superior fissure, which is thought to be the site of storage for acquired internal models. Thus we found that motor transfer is associated with brain activation that typically characterizes late learning and storage. Transfer seems to involve retrieval of a previously formed motor memory, allowing the learner to move more quickly through the early stage of learning.
新运动技能的习得依赖于任务练习。在运动迁移的情况下，类似技能的先前练习可以促进学习。尽管众多研究已经探究了对技能习得有贡献的脑区，但与迁移时出现的节省现象相关的神经基础尚未确定。在当前研究中，我们使用功能磁共振成像来检查在视觉运动适应任务的习得和迁移过程中大脑激活是如何不同的。两组参与者依次将手动瞄准动作适应反馈显示器的三种不同旋转，每次旋转之间恢复到基线显示条件。当受试者有先前的适应性经验时（即学习的正迁移），他们在适应速度上表现出节省。这种节省与通常在适应过程早期被招募的脑区活动减少有关，包括右下额叶回、初级运动皮层、颞下回和小脑（内侧HIII）。此外，尽管这些区域的激活在受试者之间与习得速度相关，但迁移时的节省程度与右侧扣带回、左侧顶上小叶、右侧顶下小叶、左侧枕中回以及小脑双侧（HV/VI）的活动相关。小脑激活发生在靠近后上裂的区域，该区域被认为是习得的内部模型的存储部位。因此我们发现运动迁移与通常表征后期学习和存储的大脑激活有关。迁移似乎涉及对先前形成的运动记忆的提取，使学习者能够更快地度过学习的早期阶段。
