Visual thalamocortical mechanisms of waking state-dependent activity and alpha oscillations

Neuron. 2022 Jan 5;110(1):120-138.e4. doi: 10.1016/j.neuron.2021.10.005. Epub 2021 Oct 22.


The brain exhibits distinct patterns of recurrent activity closely related to behavioral state. The neural mechanisms that underlie state-dependent activity in the awake animal are incompletely understood. Here, we demonstrate that two types of state-dependent activity, rapid arousal/movement-related signals and a 3-5 Hz alpha-like rhythm, in the primary visual cortex (V1) of mice strongly correlate with activity in the visual thalamus. Inactivation of V1 does not interrupt arousal/movement signals in most visual thalamic neurons, but it abolishes the 3-5 Hz oscillation. Silencing of the visual thalamus similarly eradicates the alpha-like rhythm and perturbs arousal/movement-related activation in V1. Intracellular recordings in thalamic neurons reveal the 3-5 Hz oscillation to be associated with rhythmic low-threshold Ca2+ spikes. Our results indicate that thalamocortical interactions through ionotropic signaling, together with cell-intrinsic properties of thalamocortical cells, play a crucial role in shaping state-dependent activity in V1 of the awake animal.

Keywords: alpha oscillation; arousal; brain state; movement; primary visual cortex; thalamus.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Arousal / physiology
  • Mice
  • Neurons / physiology
  • Thalamus* / physiology
  • Wakefulness* / physiology