Neurological Rehabilitation Section, Department of Neurology, University Clinic Jena, Germany.
Neuroimage. 2012 Feb 15;59(4):3364-72. doi: 10.1016/j.neuroimage.2011.10.089. Epub 2011 Nov 12.
Gray matter (GM) changes have been described after short learning tasks that lasted for 7 days or after external stimulation that lasted for 5 days. However, the early time course of training-dependent GM changes is still unknown. We investigated whether shorter motor training sessions (four times of 30 min training) would induce GM changes. Therefore, T1-weighted MRIs were acquired daily. Because reported GM changes were induced by learning, a close relationship was assumed between the functional activity and the GM changes. Therefore, fMRI was performed in addition to daily T1-weighted MRIs. At the end of the four training sessions (at time point "post"), the test results of the trained motor skill were associated with an increase of GM in secondary cortical motor areas (dPMC(right), dPMC(left), SMA(left) and the right inferior parietal lobule, IPL(right)). The earliest time point at which a GM change was detected was 1day before in the right ventral striatum (by contrasting daily T1-weighted MRI vs. baseline). To analyze whether this very early GM change within the right ventral striatum is associated with those GM changes at time point post (which were associated with motor skill performance), their functional connectivity was investigated over the time period of motor skill training. This analysis revealed an increase of functional coupling between these regions (striatum and cortex) over the training days. The current data demonstrate training-induced short GM plasticity is paralleled by their temporally dynamical process of functional interaction between the cortex and the striatum in response to a motor skill training.
灰质（GM）变化在学习任务持续 7 天或外部刺激持续 5 天后被描述。然而，训练相关 GM 变化的早期时间进程仍然未知。我们研究了较短的运动训练课程（四次每次 30 分钟的训练）是否会引起 GM 变化。因此，每天采集 T1 加权 MRI。因为报告的 GM 变化是由学习引起的，所以假设功能活动与 GM 变化之间存在密切关系。因此，除了每天的 T1 加权 MRI 外，还进行了 fMRI。在四次训练课程结束时（在“后”时间点），与训练运动技能的测试结果相关联的是次级皮质运动区（右 dPMC、左 dPMC、左 SMA 和右下顶叶，IPL（右））的 GM 增加。最早检测到 GM 变化的时间点是右腹侧纹状体的前 1 天（通过对比每日 T1 加权 MRI 与基线）。为了分析右腹侧纹状体中这种非常早期的 GM 变化是否与后时间点（与运动技能表现相关）的 GM 变化相关，研究了它们在运动技能训练期间的功能连接。该分析揭示了这些区域（纹状体和皮质）之间功能耦合的增加。目前的数据表明，训练引起的短期 GM 可塑性与皮质和纹状体之间响应运动技能训练的功能相互作用的时间动态过程平行。
