Effects of light on human circadian rhythms, sleep and mood

Somnologie - Schlafforschung und Schlafmedizin, Journal Year: 2019, Volume and Issue: 23(3), P. 147 - 156

Published: Aug. 20, 2019

Humans live in a 24-hour environment, which light and darkness follow diurnal pattern. Our circadian pacemaker, the suprachiasmatic nuclei (SCN) hypothalamus, is entrained to solar day via pathway from retina synchronises our internal biological rhythms. Rhythmic variations ambient illumination impact behaviours such as rest during sleep activity wakefulness well their underlying processes. Rather recently, availability of artificial has substantially changed especially evening night hours. This may increase risk developing rhythm sleep-wake disorders (CRSWD), are often caused by misalignment endogenous rhythms external light-dark cycles. While exact relationship between CRSWD remains be established, nocturnal been shown alter humans. On other hand, can also used an effective noninvasive therapeutic option with little no side effects, improve sleep,mood general well-being. article reviews current state knowledge regarding effects on rhythms, sleep, mood.

Language: Английский

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Melanopsin and the Intrinsically Photosensitive Retinal Ganglion Cells: Biophysics to Behavior

Neuron, Journal Year: 2019, Volume and Issue: 104(2), P. 205 - 226

Published: Oct. 1, 2019

Language: Английский

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Standards in Pupillography

Frontiers in Neurology, Journal Year: 2019, Volume and Issue: 10

Published: Feb. 21, 2019

The number of research groups studying the pupil is increasing, as publications. Consequently, new standards in pupillography are needed to formalize methodology including recording conditions, stimulus characteristics, well suitable parameters evaluation. Since description intrinsically photosensitive retinal ganglion cells (ipRGCs) there has been an increased interest and broader application ophthalmology other fields psychology chronobiology. Colour plays important role not only but also clinical observational therapy studies like gene hereditary degenerations psychopathology. Stimuli can vary size, brightness, duration, wavelength. Stimulus paradigms determine whether rhodopsin-driven rod responses, opsin-driven cone or melanopsin-driven ipRGC responses primarily elicited. Background illumination, adaptation state, instruction for participants will furthermore influence results. This standard recommends a minimum set variables be used specified publication methodologies. Initiated at 32nd International Pupil Colloquium 2017 Morges, Switzerland, aim this manuscript outline based on current knowledge experience experts order achieve greater comparability pupillographic studies. Such particularly facilitate proper by researchers field. First we describe general standards, followed specific suggestions concerning demands different targets research: afferent efferent reflex arc, pharmacology, psychology, sleepiness-related animal

Language: Английский

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Melanopsin contributions to non-visual and visual function

Current Opinion in Behavioral Sciences, Journal Year: 2019, Volume and Issue: 30, P. 67 - 72

Published: July 27, 2019

Melanopsin is a short-wavelength-sensitive photopigment that was discovered only around 20 years ago. It expressed in the cell bodies and processes of subset retinal ganglion cells retina (the intrinsically photosensitive cells; ipRGCs), thereby allowing them to signal light even absence cone rod input. Many fundamental properties melanopsin signalling humans for both visual (e.g. detection, discrimination, brightness estimation) non-visual function melatonin suppression, circadian phase shifting) remain be elucidated. Here, we give an overview what know about contributions function.

Language: Английский

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Melanopsin photoreception contributes to human visual detection, temporal and colour processing

Scientific Reports, Journal Year: 2018, Volume and Issue: 8(1)

Published: Feb. 23, 2018

Abstract The visual consequences of melanopsin photoreception in humans are not well understood. Here we studied using a technique photoreceptor silent substitution with five calibrated spectral lights after minimising the effects individual differences optical pre-receptoral filtering and desensitising penumbral cones shadow retinal blood vessels. We demonstrate that putative melanopsin-mediated image-forming vision corresponds to an opponent S-OFF L + M-ON response property, average temporal resolution up approximately 5 Hz, >10x higher thresholds than red-green colour vision. With capacity for signalling integrating slowly changing lights, melanopsin-expressing intrinsically photosensitive ganglion cells maybe fifth type peripheral

Language: Английский

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Light Modulation of Human Clocks, Wake, and Sleep

Clocks & Sleep, Journal Year: 2019, Volume and Issue: 1(1), P. 193 - 208

Published: March 13, 2019

Light, through its non-imaging forming effects, plays a dominant role on myriad of physiological functions, including the human sleep-wake cycle. The non-image effects light heavily rely specific properties such as intensity, duration, timing, pattern, and wavelengths. Here, we address how influence sleep wakefulness in humans acute e.g., alertness, and/or circadian timing system. Of critical relevance, discuss different characteristics exposure across 24-h day can lead to changes propensity, architecture, wake electroencephalogram (EEG) power spectra. Ultimately, knowledge affects improve settings at home workplace health well-being optimize treatments chronobiological disorders.

Language: Английский

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Form vision from melanopsin in humans

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: May 22, 2019

Abstract Detection and discrimination of spatial patterns is thought to originate with photoreception by rods cones. Here, we investigated whether the inner-retinal photoreceptor melanopsin could represent a third origin for form vision. We developed 4-primary visual display capable presenting differing in contrast vs cones, generated spectrally distinct stimuli that were indistinguishable cones (metamers) but presented melanopsin. Healthy observers detect sinusoidal gratings formed these metamers when peripheral retina at low (≤0.8 cpd) temporal (≤0.45 Hz) frequencies, Michelson contrasts ≥14% Metameric became invisible lower light levels (<10 13 photons cm −2 sr −1 s ) are more active. The addition metameric increases altered appearance greyscale representations coarse range everyday images. These data identify as new potential aspects vision humans.

Language: Английский

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The Lighting Environment, Its Metrology, and Non-visual Responses

Frontiers in Neurology, Journal Year: 2021, Volume and Issue: 12

Published: March 4, 2021

International standard CIE S 026:2018 provides lighting professionals and field researchers in chronobiology with a method to characterize light exposures respect non-visual photoreception responses. This defines five spectral sensitivity functions that describe optical radiation for its ability stimulate each of the α-opic retinal photoreceptor classes contribute effects humans via intrinsically-photosensitive ganglion cells (ipRGCs). The also recently published an open-access toolbox calculates all quantities ratios metrology photometric, radiometric photon systems, based on either measured (user-defined) spectrum or selected illuminants (A, D65, E, FL11, LED-B3) built into toolbox. For wide variety ecologically-valid conditions, melanopsin-based ipRGCs has been shown account responses, from shifting timing nocturnal sleep melatonin secretion regulating steady-state pupil diameter. Recent findings continue confirm photopigment melanopsin plays role visual may have significant influence brightness perception aspects spatial vision. Although knowledge concerning extent which rods cones interact driving is still growing, position statement used melanopic equivalent daylight (D65) illuminance preliminary guidance applying “proper at proper time” manipulate Further this approach awaited participants 2nd Workshop Circadian Neurophysiological Photometry (in Manchester, August 2019). new 026 enables traceable measurements formal, quantitative specification personal exposures, photic interventions designs. Here, we apply everyday sources including natural time series, range LED products and, using toobox, smartphone display screen. collection examples suggests ways variations content over day can be adopted strategies use support human health well-being.

Language: Английский

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Increased brightness assimilation in rod vision

iScience, Journal Year: 2025, Volume and Issue: 28(2), P. 111609 - 111609

Published: Jan. 5, 2025

Our visual system uses contextual cues to estimate the brightness of surfaces: can shift toward (assimilation) or away from (contrast) surroundings. We investigated induction at different light levels and found a potential influence rod photoreceptors on induction. then used novel tetrachromatic display generate stimuli differentially exciting rods cones fixed adaptation level. Under vision, assimilation was enhanced while contrast not altered in comparison cone vision. ruled out that this effect mediated by low resolution night findings suggest vision affects high-level interpretation scenes results differences but contrast. imply employs more perceptual inferences under than solve ambiguities complex spatial displays.

Language: Английский

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Melanopsin-mediated pupil function is impaired in Parkinson’s disease

Scientific Reports, Journal Year: 2018, Volume and Issue: 8(1)

Published: May 11, 2018

Abstract Parkinson’s disease (PD) is characterised by non-motor symptoms including sleep and circadian disruption. Melanopsin-expressing intrinsically photosensitive Retinal Ganglion Cells (ipRGC) transmit light signals to brain areas controlling rhythms the pupil reflex. To determine if observed in PD are linked ipRGC dysfunction, we evaluated melanopsin rod/cone contributions response medicated participants with ( n = 17) controls 12). Autonomic tone was measuring pupillary unrest darkness. In group, there evidence for an attenuated post-illumination (PIPR) amplitude reduced constriction amplitude, PIPR amplitudes did not correlate measures of quality, retinal nerve fibre layer thickness, severity, or medication dosage. Both groups exhibited similar unrest. We show that melanopsin- rod/cone-photoreceptor control pathway impaired people early-stage who have no clinically observable ophthalmic abnormalities. Given ipRGCs project targets involved arousal, rhythms, dysfunction may underpin some PD.

Language: Английский

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