Arousal fluctuations govern oscillatory transitions between dominant gamma and alpha occipital activity during eyes open/closed conditions - Archive ouverte HAL Access content directly
Journal Articles Brain Topography: a Journal of Cerebral Function and Dynamics Year : 2021

Arousal fluctuations govern oscillatory transitions between dominant gamma and alpha occipital activity during eyes open/closed conditions

(1) , (2)
1
2
Axel Hutt
Jérémie Lefebvre
  • Function : Author
  • PersonId : 1085597

Abstract

Arousal results in widespread activation of brain areas to increase their response in task and behavior relevant ways. Mediated by the Ascending Reticular Arousal System (ARAS), arousal-dependent inputs interact with neural circuitry to shape their dynamics. In the occipital cortex, such inputs may trigger shifts between dominant oscillations, where α activity is replaced by γ activity, or vice versa. A salient example of this are spectral power alternations observed while eyes are opened and/or closed. These transitions closely follow fluctuations in arousal, suggesting a common origin.To better understand the mechanisms at play, we developed and analyzed a computational model composed of two modules: a thalamocortical feedback circuit coupled with a superficial cortical network. Upon activation by noise-like inputs originating from the ARAS, our model is able to demonstrate that noise-driven nonlinear interactions mediate transitions in dominant peak frequency, resulting in the simultaneous suppression of α limit cycle activity and the emergence of γ oscillations through coherence resonance. Reduction in input provoked the reverse effect-leading to anticorrelated transitions between α and γ power. Taken together, these results shed a new light on how arousal shapes oscillatory brain activity.
Fichier principal
Vignette du fichier
manuscript_final.pdf (659.34 Ko) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-03059171 , version 1 (12-12-2020)

Identifiers

Cite

Axel Hutt, Jérémie Lefebvre. Arousal fluctuations govern oscillatory transitions between dominant gamma and alpha occipital activity during eyes open/closed conditions. Brain Topography: a Journal of Cerebral Function and Dynamics, 2021, ⟨10.1007/s10548-021-00855-z⟩. ⟨hal-03059171⟩
114 View
143 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More