LEDs for photons, physiology and food

Nature, Journal Year: 2018, Volume and Issue: 563(7732), P. 493 - 500

Published: Nov. 1, 2018

Language: Английский

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Recommendations for daytime, evening, and nighttime indoor light exposure to best support physiology, sleep, and wakefulness in healthy adults

PLoS Biology, Journal Year: 2022, Volume and Issue: 20(3), P. e3001571 - e3001571

Published: March 17, 2022

Ocular light exposure has important influences on human health and well-being through modulation of circadian rhythms sleep, as well neuroendocrine cognitive functions. Prevailing patterns do not optimally engage these actions for many individuals, but advances in our understanding the underpinning mechanisms emerging lighting technologies now present opportunities to adjust promote optimal physical mental performance. A newly developed, international standard provides a SI-compliant way quantifying influence intrinsically photosensitive, melanopsin-expressing, retinal neurons that mediate effects. The report recommendations lighting, based an expert scientific consensus expressed easily measured quantity (melanopic equivalent daylight illuminance (melaponic EDI)) defined within this standard. are supported by detailed analysis sensitivity circadian, neuroendocrine, alerting responses ocular provide straightforward framework inform design practice.

Language: Английский

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Blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans

Journal of Applied Physiology, Journal Year: 2010, Volume and Issue: 110(3), P. 619 - 626

Published: Dec. 17, 2010

Light suppresses melatonin in humans, with the strongest response occurring short-wavelength portion of spectrum between 446 and 477 nm that appears blue. Blue monochromatic light has also been shown to be more effective than longer-wavelength for enhancing alertness. Disturbed circadian rhythms sleep loss have described as risk factors astronauts NASA ground control workers, well civilians. Such disturbances can result impaired alertness diminished performance. Prior exposing subjects from light-emitting diodes (LEDs) (peak λ = 469 nm; 1/2 peak bandwidth 26 nm), ocular safety exposure blue LED was confirmed by an independent hazard analysis using American Conference Governmental Industrial Hygienists limits. Subsequently, a fluence-response curve developed plasma suppression healthy (n 8; mean age 23.9 ± 0.5 years) exposed range irradiances light. Subjects freely reactive pupils were 2:00 3:30 AM. Blood samples collected before after exposures quantified melatonin. The results demonstrate increasing narrowband blue-appearing elicit (P < 0.0001). data fit sigmoidal (R(2) 0.99; ED(50) 14.19 μW/cm(2)). A comparison 40 μW/cm(2) 4,000 K broadband white fluorescent light, currently used most general lighting fixtures, suggests narrow may stronger suppressing

Language: Английский

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Human responses to bright light of different durations

The Journal of Physiology, Journal Year: 2012, Volume and Issue: 590(13), P. 3103 - 3112

Published: April 24, 2012

Light exposure in the early night induces phase delays of circadian rhythm melatonin humans. Previous studies have investigated effect timing, intensity, wavelength, history and pattern light stimuli on human timing system. We present results from a study duration–response relationship to phase-delaying bright light. Thirty-nine young healthy participants (16 female; 22.18±3.62 years) completed 9-day inpatient study. Following three baseline days, underwent an initial assessment procedure dim (<3 lux), were then randomized for pulse (∼10,000 lux) 0.2 h, 1.0 2.5 h or 4.0 duration during 4.5 controlled-posture episode centred 16 wake episode. After another 8 sleep episode, second assessment. Phase shifts calculated difference clock time onset (DLMO) between final assessments. Exposure varying durations reset pacemaker dose-dependent, non-linear manner. Per minute exposure, was over 5 times more effective at delaying (1.07±0.36 h) as compared with (2.65±0.24 h). Acute suppression subjective sleepiness also had dose-dependent response duration. These provide strong evidence resetting

Language: Английский

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A “Melanopic” Spectral Efficiency Function Predicts the Sensitivity of Melanopsin Photoreceptors to Polychromatic Lights

Journal of Biological Rhythms, Journal Year: 2011, Volume and Issue: 26(4), P. 314 - 323

Published: July 19, 2011

Photoreception in the mammalian retina is not restricted to rods and cones but extends a small number of intrinsically photosensitive retinal ganglion cells expressing photopigment melanopsin. These mRGCs are especially important contributors circadian entrainment, pupil light reflex, other so-called nonimage-forming (NIF) responses. The spectral sensitivity melanopsin phototransduction has been addressed several species by comparing responses range monochromatic stimuli. resultant action spectra match predicted profile an opsin:vitamin A–based (nomogram) with peak (λ max ) around 480 nm. It would be most useful able use this function predict melanopsin’s broad-spectrum, including “white,” lights. However, evidence that bistable pigment intrinsic light-dependent bleach recovery mechanism raises possibility more complex relationship between quality photoreceptor response. Here, we set out empirically determine whether simply weighting optical power at each wavelength according 480-nm nomogram integrating across spectrum could variety polychromatic We show pupillomotor mice relying solely on for their photosensitivity ( rd/rd cl) can indeed accurately using methodology. Our data therefore suggest may employed as basis new photometric measure intensity (which term “melanopic”) relevant photoreception. They further measuring these terms predicts response divergent composition much reliably than methods quantifying irradiance or illuminance currently widespread use.

Language: Английский

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Daylight and health: A review of the evidence and consequences for the built environment

Lighting Research & Technology, Journal Year: 2013, Volume and Issue: 47(1), P. 6 - 27

Published: Nov. 7, 2013

Daylight has been associated with multiple health advantages. Some of these claims are associations, hypotheses or beliefs. This review presents an overview a scientific literature search on the proven effects daylight exposure human health. Studies were identified strategy across two main databases. Additionally, was performed based specific effects. The results diverse and either physiological psychological. A rather limited statistically significant well-documented proof for association between its potential consequences found. However, terms made it possible to create first subdivision associations daylight, leading practical implementations building design.

Language: Английский

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Melanopsin and Rod–Cone Photoreceptors Play Different Roles in Mediating Pupillary Light Responses during Exposure to Continuous Light in Humans

Journal of Neuroscience, Journal Year: 2012, Volume and Issue: 32(41), P. 14242 - 14253

Published: Oct. 10, 2012

In mammals, the pupillary light reflex is mediated by intrinsically photosensitive melanopsin-containing retinal ganglion cells that also receive input from rod–cone photoreceptors. To assess relative contribution of melanopsin and photoreceptors to in humans, we compared responses normally sighted individuals ( n = 24) with a blind individual lacking function. Here, show visual are required for normal continuous exposure at low irradiance levels, sustained constriction during long-wavelength portion spectrum. absence function, pupillomotor slow sustained, cannot track intermittent stimuli, suggesting rods/cones encoding fast modulations intensity. individuals, decreased monotonically least 30 min low-irradiance light, indicating steady-state an order magnitude slower than previously reported. Exposure green (543 nm; 0.1–4 Hz) min, which was given activate cone repeatedly, elicited were more twice as great light. Our findings demonstrate nonredundant roles mediating Moreover, our results suggest it might be possible enhance nonvisual exposures using repeatedly humans.

Language: Английский

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Melanopic illuminance defines the magnitude of human circadian light responses under a wide range of conditions

Journal of Pineal Research, Journal Year: 2020, Volume and Issue: 69(1)

Published: April 5, 2020

Abstract Ocular light drives a range of nonvisual responses in humans including suppression melatonin secretion and circadian phase resetting. These are driven by intrinsically photosensitive retinal ganglion cells (ipRGCs) which combine intrinsic, melanopsin‐based, phototransduction with extrinsic rod/cone‐mediated signals. As result this arrangement, it has remained unclear how best to quantify predict its effects. To address this, we analysed data from nineteen different laboratory studies that measured suppression, resetting and/or alerting wide array stimulus types, intensities durations or without pupil dilation. Using newly established SI‐compliant metrics ipRGC‐influenced light, show melanopic illuminance consistently provides the available predictor for human system. In almost all cases, is able fully account differences sensitivity stimuli varying spectral composition, acting drive track variations illumination characteristic those encountered over civil twilight (~1‐1000 lux equivalent daylight illuminance). Collectively, our demonstrate widespread utility as metric predicting impact environmental illumination. therefore provide strong support use basis guidelines seek regulate exposure benefit health inform future lighting design.

Language: Английский

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Global rise of potential health hazards caused by blue light-induced circadian disruption in modern aging societies

npj Aging and Mechanisms of Disease, Journal Year: 2017, Volume and Issue: 3(1)

Published: June 12, 2017

Mammals receive light information through the eyes, which perform two major functions: image forming vision to see objects and non-image adaptation of physiology behavior light. Cone rod photoreceptors form images send via retinal ganglion cells brain for reconstruction. In contrast, nonimage-forming photoresponses vary widely from adjustment pupil diameter circadian clock. responses are mediated by expressing photopigment melanopsin. Melanopsin-expressing constitute 1-2% in adult mammalian retina, intrinsically photosensitive, integrate photic rods cones control adaptation. Action spectra ipRGCs melanopsin peak around 480 nm blue Understanding function lets us recognize considerable physiological effects light, is increasingly important our modern society that uses light-emitting diode. Misalignment rhythmicity observed numerous conditions, including aging, thought be involved development age-related disorders, such as depression, diabetes, hypertension, obesity, cancer. The appropriate regulation proper lighting therefore essential. This perspective introduces potential risks excessive human health rhythm disruption sleep deprivation. Knowing positive negative aspects, this study claims importance being exposed at optimal times intensities during day, based on concept clock, ultimately improve quality life have a healthy longer life.

Language: Английский

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Melatonin suppression is exquisitely sensitive to light and primarily driven by melanopsin in humans

Journal of Pineal Research, Journal Year: 2019, Volume and Issue: 66(4)

Published: Jan. 30, 2019

Light elicits a range of non-visual responses in humans. Driven predominantly by intrinsically photosensitive retinal ganglion cells (ipRGCs), but also rods and/or cones, these include melatonin suppression. A sigmoidal relationship has been established between suppression and light intensity; however, photoreceptoral involvement remains unclear.In this study, we first modelled the relationships alpha-opic illuminances using an extensive dataset Brainard colleagues. Our results show that (a) is better predicted melanopic illuminance compared to other illuminances, (b) occur at levels as low ~1.5 lux (melanopsin-weighted irradiance 0.2 µW/cm2 ), (c) saturation occurs 305 36.6 ). We then tested melanopsin-weighted illuminance-response model derived from colleagues' data it predicts equally well our laboratory, although obtained different intensities exposure duration.Together, findings suggest monochromatic lights driven melanopsin can be initiated extremely experimental conditions. This emphasizes concern impacts lighting design light-emitting devices.

Language: Английский

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