Surprisingly little is known about neural activity in the sleeping cerebellum. Using long-term wireless recording, we characterised dynamic cerebro-thalamo-cerebellar interactions during natural sleep in monkeys. Similar sleep cycles were evident in both M1 and cerebellum as cyclical fluctuations in firing rates as well as a reciprocal pattern of slow waves and sleep spindles. Directed connectivity from motor cortex to the cerebellum suggested a neocortical origin of slow waves. Surprisingly however, spindles were associated with a directional influence from the cerebellum to motor cortex, conducted via the thalamus. Furthermore, the relative phase of spindle-band oscillations in the neocortex and cerebellum varied systematically with their changing amplitudes. We used linear dynamical systems analysis to show that this behaviour could only be explained by a system of two coupled oscillators. These observations appear inconsistent with a single spindle generator within the thalamo-cortical system, and suggest instead a cerebellar contribution to neocortical sleep spindles. Since spindles are implicated in the off-line consolidation of procedural learning, we speculate that this may involve communication via cerebello-thalamo-neocortical pathways in sleep.

令人惊讶的是，人们对睡眠小脑的神经活动知之甚少。使用长期无线记录，我们描述了猴子自然睡眠期间的动态脑-丘脑-小脑相互作用。类似的睡眠周期在 M1 和小脑中都很明显，因为放电率的周期性波动以及慢波和睡眠纺锤波的交互模式。从运动皮层到小脑的定向连接表明慢波的新皮层起源。然而，令人惊讶的是，纺锤体与通过丘脑传导的从小脑到运动皮层的定向影响有关。此外，新皮质和小脑中纺锤带振荡的相对相位随着它们的变化幅度而系统地变化。我们使用线性动力系统分析来表明这种行为只能由两个耦合振荡器的系统来解释。这些观察结果似乎与丘脑皮质系统内的单个纺锤体发生器不一致，而是表明小脑对新皮质睡眠纺锤体的贡献。由于纺锤体与程序学习的离线巩固有关，我们推测这可能涉及睡眠中通过小脑-丘脑-新皮质通路进行的交流。