Summary
This review outlines how light acts as the primary zeitgeber to entrain the suprachiasmatic nuclei (SCN) master clock via photoreception pathways and molecular feedback loops. Understanding these mechanisms is foundational for designing lighting interventions that effectively shift or maintain circadian phase in clinical and workplace settings.
Key Findings
- The SCN functions as the master circadian clock through a transcriptional-translational feedback loop that must be continuously reset by photic input.
- Light is the dominant zeitgeber in mammals, with photic signals integrated alongside non-photic cues in the SCN to maintain circadian alignment.
- Multiple regulatory molecular factors contribute to photic entrainment, suggesting that lighting interventions targeting specific photoreception pathways may offer precision circadian control.
Categories
Sleep & Circadian Health: Reviews the mechanisms of photic entrainment, directly relevant to understanding how light resets the master circadian clock.
The Science of Light: Details photoreception pathways including ipRGCs and molecular signaling in the SCN that underpin light-based circadian regulation.
Author(s)
A Ashton, RG Foster, A Jagannath
Publication Year
2022
Number of Citations
44
Related Publications
Sleep & Circadian Health
- Phototransduction by retinal ganglion cells that set the circadian clock
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- The twoâprocess model of sleep regulation: a reappraisal
- Melanopsin is required for non-image-forming photic responses in blind mice
- Strange vision: ganglion cells as circadian photoreceptors
The Science of Light
- Phototransduction by retinal ganglion cells that set the circadian clock
- Color appearance models
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Melanopsin is required for non-image-forming photic responses in blind mice