Recent evidence suggests that gains in performance observed while humans learn a novel motor sequence occur during the quiet rest periods interleaved with practice (micro-offline gains, MOGs). This phenomenon is reminiscent of memory replay observed in the hippocampus during spatial learning in rodents. Whether the hippocampus is also involved in the production of MOGs remains currently unknown. Using a multimodal approach in humans, here we show that activity in the hippocampus and the precuneus increases during the quiet rest periods and predicts the level of MOGs before asymptotic performance is achieved. These functional changes were followed by rapid alterations in brain microstructure in the order of minutes, suggesting that the same network that reactivates during the quiet periods of training undergoes structural plasticity. Our work points to the involvement of the hippocampal system in the reactivation of procedural memories.

最近的证据表明，人们在学习新的运动序列时观察到的性能提升发生在与练习交错的安静休息期（微脱机增益，MOG）。这种现象让人联想到在啮齿动物进行空间学习时在海马中观察到的记忆重现。目前尚不清楚海马是否也参与MOG的产生。在人类中使用多模式方法，在这里我们表明，在安静的休息时间里，海马和前胎的活动增加，并预测了渐近表现之前的MOG水平。这些功能性变化之后，大脑微结构在几分钟内迅速变化，这表明在安静的训练期间重新激活的同一网络经历了结构可塑性。