Laboratory for Brain Recovery and Function, School of Physiotherapy and Department of Psychology, Dalhousie University, Halifax, NS, Canada.
J Neurosci Methods. 2012 Aug 15;209(2):308-19. doi: 10.1016/j.jneumeth.2012.06.016. Epub 2012 Jun 26.
There is a continuing need to improve understanding of the central nervous system control of learning. Specifically, there is a need to examine the characteristics of cortical and sub-cortical activity linked to the stages of motor learning, including those occurring within a single-session. In this study we sought to design and investigate a visuomotor task to determine its ability to assess the component of motor learning occurring during a single session of fMRI (i.e., the 'online' improvement in motor performance). Fourteen healthy control subjects performed a visuomotor task requiring a combination of bilateral grip force to accurately move a cursor towards a target. We assessed online motor learning by comparing behavioural measures (accuracy and error magnitude) and the extent of spatial activation in specific brain regions of interest (ROIs) using fMRI pre- and post-training. Results showed a training-related improvement in performance based on increased accuracy (p<0.0125) and decreased error magnitude (p<0.0125) from pre- to post-training. Decreases in the extent of spatial activation from pre- to post-training in the majority of ROIs supported a training-related attenuation in brain activity associated with online motor learning. Importantly, decreases in error magnitude across conditions (p<0.05) confirmed that improvements in performance continued over the entire course of the experiment. Establishing this task may permit more extensive study of the neural correlates of single-session, online learning in healthy individuals and those with motor control challenges. Information obtained from such studies may provide an opportunity to improve interventions in neurological rehabilitation.
人们一直需要加深对中枢神经系统控制学习的理解。具体而言，需要研究与运动学习阶段相关联的皮质和皮质下活动的特征，包括在单个会话中发生的那些活动。在这项研究中，我们试图设计并研究一个视觉运动任务，以确定其评估 fMRI 单次会话中运动学习组成部分（即运动表现的“在线”改善）的能力。14 名健康对照者执行了一个视觉运动任务，该任务需要双侧握力的组合，以准确地将光标移动到目标上。我们通过比较行为测量（准确性和误差幅度）以及使用 fMRI 在训练前后评估特定感兴趣脑区（ROI）的空间激活程度来评估在线运动学习。结果显示，基于从训练前到训练后的准确性提高（p<0.0125）和误差幅度减小（p<0.0125），表现出与训练相关的改善。从训练前到训练后的大多数 ROI 的空间激活程度的降低支持与在线运动学习相关的大脑活动的训练相关衰减。重要的是，条件之间的误差幅度降低（p<0.05）证实了在整个实验过程中，性能的提高仍在继续。建立此任务可能会允许更广泛地研究健康个体和运动控制挑战个体单次会话、在线学习的神经相关性。从这些研究中获得的信息可能为神经康复干预措施提供机会。
