Melatonin Suppression by Light in Humans Is More Sensitive Than Previously Reported.
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ABSTRACT:
SUBMITTER: Vartanian GV
PROVIDER: S-EPMC4499476 | biostudies-literature | 2015 Aug
REPOSITORIES: biostudies-literature
Publications
Melatonin Suppression by Light in Humans Is More Sensitive Than Previously Reported.
Vartanian Garen V GV Li Benjamin Y BY Chervenak Andrew P AP Walch Olivia J OJ Pack Weston W Ala-Laurila Petri P Wong Kwoon Y KY
Journal of biological rhythms 20150527 4
The retina drives various non-image-forming photoresponses, including circadian photoentrainment and pupil constriction. Previous investigators showed that in humans, photic suppression of the clock-controlled hormone melatonin is most sensitive to 460-nm blue light, with a threshold of ~12 log photons cm(-2) s(-1). This threshold is surprising because non-image-forming vision is mediated by intrinsically photosensitive retinal ganglion cells, which receive rod-driven synaptic input and can resp ...[more]
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