In 1923, scientists observed blind mice responding to light.
"Blind Mice", Keeler C. (1928)
The blind mice's light reflex suggested the existence of a new photoreceptor in the ganglion cell layer of the retina.
"Melanopsin-expressing, Intrinsically Photosensitive Retinal Ganglion Cells (ipRGCs)", Graham D. and and Wong K. (2008)
This photoreceptor was found to contain the photopigment melanopsin, with peak absorption in the blue light range.
"A Novel Human Opsin in the Inner Retina", Provencio et. al. (2000)
These cells, known as intrinsically photosensitive retinal ganglion cells (ipRGCs), play a major role in synchronizing circadian rhythms to a 24 hour light/dark cycle.
As the amount of blue light in the sky changes throughout the day....
... the human brain responds to the change in blue light.
More blue makes you alert.
Less blue helps you sleep.
"The Effects of Red and Blue Lights on Circadian Variations in Cortisol, Alpha Amylase, and Melatonin" Rea and Figueiro (2010)
"Light as a central modulator of circadian rhythms, sleep, and affect" LeGates, Fernandez, and Hatter (2014)
An abundance of case studies and peer-reviewed articles show that this naturally occurring phenomenon can be mimicked by tunable lighting products.
Schools
- "Applicability and efficacy of variable light in schools" Barkmann, Wessolowski, Schulte-Markwort (2012)
- "Influence of blue-enriched classroom lighting on students' cognitive performance" Keis, Helbig, Streb, Hille (2014)
- "Lighting affects students’ concentration positively: Findings
from three Dutch studies" van der Zanden et. al. (2012) - "Short-Wavelength Light Enhances Cortisol Awakening Response in Sleep-Restricted Adolescents" Rea et. al. (2012)
Nursing Homes
Psychiatric Wards
Offices
Prisons