Time-of-day-dependent effects of bright light exposure on human psychophysiology: comparison of daytime and nighttime exposure DOI

Melanie Rüger,

Marijke C. M. Gordijn, Domien G. M. Beersma

et al.

AJP Regulatory Integrative and Comparative Physiology, Journal Year: 2005, Volume and Issue: 290(5), P. R1413 - R1420

Published: Dec. 23, 2005

Bright light can influence human psychophysiology instantaneously by inducing endocrine (suppression of melatonin, increasing cortisol levels), other physiological changes (enhancement core body temperature), and psychological (reduction sleepiness, increase alertness). Its broad range action is reflected in the wide field applications, ranging from optimizing a work environment to treating depressed patients. For optimally applying bright understanding its mechanism, it crucial know whether effects depend on time day. In this paper, we report given at two different times day parameters. Twenty-four subjects participated experiments (n = 12 each). All were nonsmoking, healthy young males (18-30 yr). both experiments, exposed either (5,000 lux) or dim <10 lux (control condition) between 12:00 P.M. 4:00 (experiment A) midnight A.M. B). Hourly measurements included salivary concentrations, electrocardiogram, sleepiness (Karolinska Sleepiness Scale), fatigue, energy ratings (Visual Analog Scale). Core temperature was measured continuously throughout experiments. had time-dependent effect heart rate temperature; i.e., exposure night, but not daytime, increased enhanced temperature. It no significant all cortisol. The variables independent, since nighttime daytime reduced fatigue significantly similarly.

Language: Английский

Melanopsin-Containing Retinal Ganglion Cells: Architecture, Projections, and Intrinsic Photosensitivity DOI
Samer Hattar,

H.–W. Liao,

Motoharu Takao

et al.

Science, Journal Year: 2002, Volume and Issue: 295(5557), P. 1065 - 1070

Published: Feb. 8, 2002

The primary circadian pacemaker, in the suprachiasmatic nucleus (SCN) of mammalian brain, is photoentrained by light signals from eyes through retinohypothalamic tract. Retinal rod and cone cells are not required for photoentrainment. Recent evidence suggests that entraining photoreceptors retinal ganglion (RGCs) project to SCN. visual pigment this photoreceptor may be melanopsin, an opsin-like protein whose coding messenger RNA found a subset RGCs. By cloning rat melanopsin generating specific antibodies, we show present cell bodies, dendrites, proximal axonal segments In mice heterozygous tau-lacZ targeted gene locus, β-galactosidase–positive RGC axons projected SCN other brain nuclei involved photoentrainment or pupillary reflex. Rat RGCs exhibited intrinsic photosensitivity invariably expressed melanopsin. Hence, most likely phototransducing set clock initiate non–image-forming functions.

Language: Английский

Citations

2542
An action spectrum for melatonin suppression: evidence for a novel non‐rod, non‐cone photoreceptor system in humans DOI

Kavita Thapan,

Joséphine Arendt, Debra J. Skene

et al.

The Journal of Physiology, Journal Year: 2001, Volume and Issue: 535(1), P. 261 - 267

Published: Aug. 1, 2001

1 Non-image forming, irradiance-dependent responses mediated by the human eye include synchronisation of circadian axis and suppression pineal melatonin production. The retinal photopigment(s) transducing these light in humans have not been characterised. 2 Using ability to suppress nocturnal production, we aimed investigate its spectral sensitivity produce an action spectrum. Melatonin was quantified 22 volunteers 215 exposure trials using monochromatic (30 min pulse administered at time (CT) 16-18) different wavelengths (λmax 424, 456, 472, 496, 520 548 nm) irradiances (0.7-65.0 μW cm−2). 3 At each wavelength, plasma increased with increasing irradiance. Irradiance-response curves (IRCs) were fitted generated half-maximal (IR50) corrected for lens filtering used construct 4 resulting spectrum showed unique short-wavelength very from classical scotopic photopic visual systems. lack fit (r2 < 0.1) our published rod cone absorption spectra precluded photoreceptors having a major role. Cryptochromes also had poor data. Fitting series Dartnall nomograms rhodopsin-based photopigments over λmax range 420-480 nm that rhodopsin templates between 457 462 data well (r2≥ 0.73). Of these, best template 459 (r2= 0.74). 5 Our strongly support primary role novel photopigment light-induced provide first direct evidence non-rod, non-cone photoreceptive system humans.

Language: Английский

Citations

1275
High Sensitivity of Human Melatonin, Alertness, Thermoregulation, and Heart Rate to Short Wavelength Light DOI Open Access
Christian Cajochen, Mirjam Münch,

Szymon Kobialka

et al.

The Journal of Clinical Endocrinology & Metabolism, Journal Year: 2005, Volume and Issue: 90(3), P. 1311 - 1316

Published: March 1, 2005

Light can elicit acute physiological and alerting responses in humans, the magnitude of which depends on timing, intensity, duration light exposure. Here, we report that response as well its effects thermoregulation heart rate are also wavelength dependent. Exposure to 2 h monochromatic at 460 nm late evening induced a significantly greater melatonin suppression than occurred with 550-nm light, concomitant increased core body temperature (∼2.8 × 1013 photons/cm2/sec for each treatment). diminished distal-proximal skin gradient, measure degree vasoconstriction, independent wavelength. Nonclassical ocular photoreceptors peak sensitivity around have been found regulate circadian rhythm function measured by phase shifting. Our findings—that human thermoregulatory sequelae blue-shifted relative three-cone visual photopic system—indicate an additional role these novel modifying alertness, thermophysiology, rate.

Language: Английский

Citations

856
Light as a central modulator of circadian rhythms, sleep and affect DOI
Tara A. LeGates, Diego C. Fernandez, Samer Hattar

et al.

Nature reviews. Neuroscience, Journal Year: 2014, Volume and Issue: 15(7), P. 443 - 454

Published: June 11, 2014

Language: Английский

Citations

851
Entrainment of the Human Circadian Clock to the Natural Light-Dark Cycle DOI Creative Commons
Kenneth P. Wright, Andrew W. McHill,

Brian R. Birks

et al.

Current Biology, Journal Year: 2013, Volume and Issue: 23(16), P. 1554 - 1558

Published: Aug. 1, 2013

Language: Английский

Citations

639
Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness DOI
Christian Cajochen, Jamie M. Zeitzer, Charles A. Czeisler

et al.

Behavioural Brain Research, Journal Year: 2000, Volume and Issue: 115(1), P. 75 - 83

Published: Oct. 1, 2000

Language: Английский

Citations

605
Short-Wavelength Sensitivity for the Direct Effects of Light on Alertness, Vigilance, and the Waking Electroencephalogram in Humans DOI Open Access
Steven W. Lockley,

BS Erin E. Evans,

Frank A. J. L. Scheer

et al.

SLEEP, Journal Year: 2006, Volume and Issue: unknown

Published: Feb. 1, 2006

To assess the wavelength-dependent sensitivity of acute effects ocular light exposure on alertness, performance, waking electroencephalogram (EEG), and cortisol.A between-subjects design was employed to compare 460-nm or 555-nm for 6.5 hours during biological night.Intensive Physiological Monitoring Unit, Brigham Women's Hospital, Boston, MA.Sixteen healthy adults (8 women; mean age +/- SD = 23.3 2.4 years).Subjects were exposed equal photon densities (2.8 x 10(13) photons cm(-2) s(-1)) either (n 8) monochromatic hours, 15 minutes after mydriasis.Subjects underwent continuous EEG/electrooculogram recordings completed a performance battery every 30 60 minutes. As compared with those light, subjects had significantly lower subjective sleepiness ratings, decreased auditory reaction time, fewer attentional failures, EEG power density in delta-theta range (0.5-5.5 Hz), increased high-alpha (9.5-10.5 Hz). Light no direct effect cortisol.Short-wavelength alerting indicates that visual photopic system is not primary photoreceptor mediating these responses light. The frequency-specific changes indicate short-wavelength powerful agent immediately attenuates negative both homeostatic sleep pressure circadian drive ability sustain attention.

Language: Английский

Citations

605
Characterization of an ocular photopigment capable of driving pupillary constriction in mice DOI
Robert J. Lucas,

Ronald H. Douglas,

Russell G. Foster

et al.

Nature Neuroscience, Journal Year: 2001, Volume and Issue: 4(6), P. 621 - 626

Published: June 1, 2001

Language: Английский

Citations

598
Alerting effects of light DOI
Christian Cajochen

Sleep Medicine Reviews, Journal Year: 2007, Volume and Issue: 11(6), P. 453 - 464

Published: Nov. 17, 2007

Language: Английский

Citations

563
The gut microbiome and metabolic syndrome DOI Open Access
Kruttika Dabke, Gustaf Hendrick, Suzanne Devkota

et al.

Journal of Clinical Investigation, Journal Year: 2019, Volume and Issue: 129(10), P. 4050 - 4057

Published: Sept. 30, 2019

The metabolic syndrome (MetS) is a constellation of risk factors that, if left untreated, will often progress to greater defects such as type 2 diabetes and nonalcoholic fatty liver disease. While these have been established for over 40 years, the definition MetS warrants reconsideration in light substantial data that emerged from studies gut microbiome. In this Review we present existing recent literature supports microbiome's potential influence on various MetS. interplay intestinal microbiota with host metabolism has shown be mediated by myriad factors, including defective barrier, bile acid metabolism, antibiotic use, pleiotropic effects microbially produced metabolites. These show events start gut, response external cues diet circadian disruption, far-reaching beyond gut.

Language: Английский

Citations

532