Communication from the cerebellum to the neocortex during sleep spindles

Prog Neurobiol. 2021 Apr:199:101940. doi: 10.1016/j.pneurobio.2020.101940. Epub 2020 Nov 5.

Abstract

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.

Keywords: Cerebellum; Sleep; Spindles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cerebellum
  • Communication
  • Electroencephalography
  • Neocortex*
  • Sleep*

Associated data

  • figshare/10.6084/m9.figshare.13200395.v1