Action Spectrum for Melatonin Suppression: Evidence for a Novel Circadian Photoreceptor in the Human Eye

Studies with monochromatic light stimuli have shown that the action spectrum for melatonin suppression exhibits its highest sensitivity at short wavelengths, around 460 to 480 nm. Other studies have demonstrated that filtering out the short wavelengths from white light reduces melatonin suppression. However, this filtering of short wavelengths was generally confounded with reduced light intensity and/or changes in color temperature. Moreover, it changed the appearance from white light to yellow/orange, rendering it unusable for many practical applications. Here, we show that selectively tuning a polychromatic white light spectrum, compensating for the reduction in spectral power between 450 and 500 nm by enhancing power at even shorter wavelengths, can produce greatly different effects on melatonin production, without changes in illuminance or color temperature. On different evenings, 15 participants were exposed to 3 h of white light with either low or high power between 450 and 500 nm, and the effects on salivary melatonin levels and alertness were compared with those during a dim light baseline. Exposure to the spectrum with low power between 450 and 500 nm, but high power at even shorter wavelengths, did not suppress melatonin compared with dim light, despite a large difference in illuminance (175 vs. <5 lux). In contrast, exposure to the spectrum with high power between 450 and 500 nm (also 175 lux) resulted in almost 50% melatonin suppression. For alertness, no significant differences between the 3 conditions were observed. These results open up new opportunities for lighting applications that allow for the use of electrical lighting without disturbance of melatonin production.

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Artificial light sources as light pollutant of humans melatonin suppression

Photonics Letters of Poland ◽

10.4302/plp.v11i3.925 ◽

2019 ◽

Vol 11 (3) ◽

pp. 78 ◽

Cited By ~ 2

Author(s):

Piotr Jakubowski

Keyword(s):

Blue Light ◽

Power Distribution ◽

Optical Radiation ◽

Spectral Power ◽

International Workshop ◽

Action Spectrum ◽

Legal Aspects ◽

Light Sources ◽

Research Technology ◽

Melatonin Suppression

Blue light emitted by LEDs might influence on natural biological rhythm of human being, what can be considered as environment pollution. In this paper the effect of the latest commercially available LEDs on melatonin suppression index (MSI) was analyzed. Research was done based on spectral power distribution of given LED (SPD) and melatonin suppression function in reference to melatonin suppression under daylight (illuminant D65). Results of calculations shows strong correlation between CCT and MSI, however MSI factor might vary for different LEDs with same CCT. Full Text: PDF ReferencesC. C. Sun, et al., Packaging efficiency in phosphor-converted white LEDs and its impact to the limit of luminous efficacy, Journal of Solid State Lighting, 1:19, (2014). CrossRef M. S. Rea, M. G. Figueiro, J. D. Bullough, "Circadian photobiology: An emerging framework for lighting practice and research", Light Research Technology Vol. 34(3), (2002). CrossRef I. Fryc, P. Jakubowski, K. Kołacz, Analysis of optical radiation parameters of compact discharge HID lamps and LED COB modules used for illuminating shop windows, Przeglad Elektrotechniczny, R. 93, No. 11, (2017). CrossRef G. C. Brainard, J. P. Hanifin, J.M. Greeson, B. Byrne, E. Gerner, D. D. Rollang, "Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor", Journal of Neuroscience vol. 21, (2001). CrossRef K. Thapan, J. Arendt, D. J. Skene, "An action spectrum for melatonin supression: evidence for a novel non-rod, non-cone photoreceptor system in humans," Journal of Physiology vol. 535, (2001). CrossRef I. Fryc, J. Fryc, P. Jakubowski, K. A. Wąsowski, Technical, medical and legal aspects of domestic light sources photobiological safety, Przeglad Elektrotechniczny, R. 93, No. 3, (2017). CrossRef J. Enzi et. al, A "Melanopic" Spectral Efficiency Function Predicts the Sensitivity of Melanopsin Photoreceptors to Polychromatic Lights Journal of biological rhytms, Vol. 26 No. 4, (2011). CrossRef M. Aube, J. Roby J, M. Kocifaj, Evaluating Potential Spectral Impacts of Various Artificial Lights on Melatonin Suppression, Photosynthesis, and Star Visibility. PLOS ONE, Vol. 8, (2013). CrossRef P. Jakubowski, I. Fryc, Metrological requirements for measurements of circadian radiation, Optica Applicata, Vol. 48 Issue 4, (2018). CrossRef P. Jakubowski, I. Fryc, Measurement methods of optical radiation in circadian active range, Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej, nr 54 (2017). DirectLink P. Jakubowski, Comparative analysis of light parameters of LEDs and OLEDs in context of blue light emission, Polish Journal for Sustainable Development 21 (2), (2017). CrossRef CIE TN003:2015, "Report on the First International Workshop on Circadian and neurophysiological Photometry", (2015). DirectLink

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An action spectrum for melatonin suppression: evidence for a novel non‐rod, non‐cone photoreceptor system in humans

The Journal of Physiology ◽

10.1111/j.1469-7793.2001.t01-1-00261.x ◽

2001 ◽

Vol 535 (1) ◽

pp. 261-267 ◽

Cited By ~ 738

Author(s):

Kavita Thapan ◽

Josephine Arendt ◽

Debra J. Skene

Keyword(s):

Action Spectrum ◽

Cone Photoreceptor ◽

Melatonin Suppression

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A New System For Optomanual Semiautomatic Quantitative Image Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078596 ◽

1977 ◽

Vol 35 ◽

pp. 210-211

Author(s):

H.P. Rohr

Keyword(s):

Image Analysis ◽

Volume Density ◽

List Type ◽

Distribution Analysis ◽

Type Number ◽

Point Counting ◽

Human Eye ◽

Quantitative Image ◽

Point Density ◽

Electronic Counting

Today, in image analysis the broadest possible rationalization and economization have become desirable. Basically, there are two approaches for image analysis: The image analysis through the so-called scanning methods which are usually performed without the human eye and the systems of optical semiautomatic analysis completely relying on the human eye.The new MOP AM 01 opto-manual system (fig.) represents one of the very promising approaches in this field. The instrument consists of an electronic counting and storing unit, which incorporates a microprocessor and a keyboard for choice of measuring parameters, well designed for easy use.Using the MOP AM 01 there are three possibilities of image analysis:the manual point counting,the opto-manual point counting andthe measurement of absolute areas and/or length (size distribution analysis included).To determine a point density for the calculation of the corresponding volume density the intercepts lying within the structure are scanned with the light pen.

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