From Fast Oscillations to Circadian Rhythms: Coupling at Multiscale Frequency Bands in the Rodent Subcortical Visual System

Abstract

The subcortical visual system (SVS) is a unique collection of brain structures localised in the thalamus, hypothalamus and midbrain. The SVS receives ambient light inputs from retinal ganglion cells and integrates this signal with internal homeostatic demands to influence physiology. During this processing, a multitude of oscillatory frequency bands coalesces, with some originating from the retinas, while others are intrinsically generated in the SVS. Collectively, these rhythms are further modulated by the day and night cycle. The multiplexing of these diverse frequency bands (from circadian to infra-slow and gamma oscillations) makes the SVS an interesting system to study coupling at multiscale frequencies. We review the functional organisation of the SVS, and the various frequencies generated and processed by its neurons. We propose a perspective on how these different frequency bands couple with one another to synchronise the activity of the SVS to control physiology and behaviour.

Metabolic cues impact non‐oscillatory intergeniculate leaflet and ventral lateral geniculate nucleus: standard versus high‐fat diet comparative study

“…Infra-slow rhythm was recorded for the first time from cortical areas, as oscillations in local field potentials. Following this, it was described in a wide variety of retinorecipient nuclei: the LGN (including the IGL/VLG), the olivary pretectal nucleus, the SCN, the lateral posterior nucleus and the superior colliculus (Aladjalova, 1957;Albrecht & Gabriel, 1994;Chrobok, Belle et al, 2021;Filippov & Frolov, 2005;Lewandowski et al, 2000Lewandowski et al, , 2002Miller & Fuller, 1992;Szkudlarek et al, 2008). These structures belong to the subcortical visual system, and their ISO pattern is synchronised within one cerebral hemisphere.…”

“…This distinctive pattern was observed in rodents exposed to constant illumination and is heavily dependent on the contralateral retinal input (Blasiak, Zawadzki et al., 2013; Chrobok, Palus et al., 2017; Lewandowski et al., 2002). ISO function has yet to be discovered, although it may be engaged in the synchronisation of subcortical visual nuclei of the same hemisphere (Chrobok, Belle et al., 2021).…”

Time-Frequency Representations of Brain Oscillations: Which One Is Better?

“…Under normal and pathological conditions, brain circuits engage in rhythmic modulations of activity called neural oscillations ( Buzsaki, 2006 ). Their frequencies span orders of magnitude, from the slow and infra-slow ones, with periods of minutes, tens of minutes, or hours ( Aladjalova, 1957 ; Hughes et al, 2011 ; Belle and Diekman, 2018 ; Chrobok et al, 2021 ), to the medium ones, including theta (4–8 Hz) or alpha (8–12 Hz), the fast ones, like beta (12–30 Hz) or gamma (30–80 Hz) ( Mureşan et al, 2008 ), and, finally, the ultra-fast ones (>100 Hz) ( Csicsvari et al, 1999 ; Hughes, 2008 ; Gourévitch et al, 2020 ). These different frequency bands are associated to different brain states.…”

Racing and Pacing in the Reward System: A Multi-Clock Circadian Control Over Dopaminergic Signalling

“…With the discovery of intrinsic clock gene expression in several extra-SCN brain nuclei, from the olfactory bulb ( Abraham, 2005 ), through thalamic ( Chrobok et al, 2021a ), epithalamic ( Guilding et al, 2010 ), hypothalamic ( Guilding et al, 2009 ) and midbrain regions ( Chrobok et al, 2021b ), all the way to the hindbrain ( Kaneko et al, 2009 ; Chrobok et al, 2020 ), it is now believed that at least a part of the rhythmic control of homeostasis must be devolved to such local clocks. These circadian timekeeping centres vary in the degree of their autonomy ( Guilding and Piggins, 2007 ; Paul et al, 2020 ; Chrobok et al, 2021c ). An ‘autonomous oscillator’ displays molecular and electrophysiological rhythms that are strongly synchronised amongst its single cells due to highly-functional connectivity within the structure.…”