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Author Brainard, G.C.; Hanifin, J.P.; Greeson, J.M.; Byrne, B.; Glickman, G.; Gerner, E.; Rollag, M.D. url  openurl
  Title (up) Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor. Type Journal Article
  Year 2001 Publication Journal of Neuroscience Abbreviated Journal  
  Volume 21 Issue Pages 6405-6412  
  Keywords Human Health  
  Abstract The photopigment in the human eye that transduces light for circadian and neuroendocrine regulation, is unknown. The aim of this study was to establish an action spectrum for light-induced melatonin suppression that could help elucidate the ocular photoreceptor system for regulating the human pineal gland. Subjects (37 females, 35 males, mean age of 24.5 ± 0.3 years) were healthy and had normal color vision. Full-field, monochromatic light exposures took place between 2:00 and 3:30 A.M. while subjects' pupils were dilated. Blood samples collected before and after light exposures were quantified for melatonin. Each subject was tested with at least seven different irradiances of one wavelength with a minimum of 1 week between each nighttime exposure. Nighttime melatonin suppression tests (n = 627) were completed with wavelengths from 420 to 600 nm. The data were fit to eight univariant, sigmoidal fluence–response curves (R 2 = 0.81–0.95). The action spectrum constructed from these data fit an opsin template (R 2 = 0.91), which identifies 446–477 nm as the most potent wavelength region providing circadian input for regulating melatonin secretion. The results suggest that, in humans, a single photopigment may be primarily responsible for melatonin suppression, and its peak absorbance appears to be distinct from that of rod and cone cell photopigments for vision. The data also suggest that this new photopigment is retinaldehyde based. These findings suggest that there is a novel opsin photopigment in the human eye that mediates circadian photoreception.  
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  Notes Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 529  
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Author Souman, J.L.; Tinga, A.M.; Te Pas, S.F.; van Ee, R.; Vlaskamp, B.N.S. url  doi
openurl 
  Title (up) Acute alerting effects of light: a systematic literature review Type Journal Article
  Year 2018 Publication Behavioural Brain Research Abbreviated Journal Behav Brain Res  
  Volume 337 Issue Pages 228-239  
  Keywords Human Health  
  Abstract Periodic, well timed exposure to light is important for our health and wellbeing. Light, in particular in the blue part of the spectrum, is thought to affect alertness both indirectly, by modifying circadian rhythms, and directly, giving rise to acute effects. We performed a systematic review of empirical studies on direct, acute effects of light on alertness to evaluate the reliability of these effects and to assess to what extent they depend on other factors, such as time of day, exposure duration and sleep pressure. In total, we identified 74 studies in which either light intensity, spectral distribution, or both were manipulated, and the effects on behavioral measures of alertness were evaluated, either subjectively or measured in performance tasks. The results show that increasing the intensity or the color temperature of polychromatic white light in general has been found to increase subjective ratings of alertness, though a substantial proportion of these studies failed to find significant effects. There is little evidence in the literature that these subjective alerting effects of light also translate into improvements on performance measures of alertness. For monochromatic or narrowband light exposure, some studies have shown improvement in reaction time tasks with exposure to blue light, but generally this was not accompanied by changes in subjective alertness. Thus, the alerting effects of light are far less clear than often suggested. We suggest that in future studies more attention should be paid to other factors that may influence the effects of light, such as chronotype, circadian phase, homeostatic state and prior light history.  
  Address Philips Research (Department Brain, Behavior & Cognition), Eindhoven, The Netherlands  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0166-4328 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28912014 Approved no  
  Call Number LoNNe @ kyba @ Serial 1727  
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Author Canazei, M.; Pohl, W.; Bliem, H.R.; Weiss, E.M. url  doi
openurl 
  Title (up) Acute effects of different light spectra on simulated night-shift work without circadian alignment Type Journal Article
  Year 2016 Publication Chronobiology International Abbreviated Journal Chronobiol Int  
  Volume 34 Issue 3 Pages 303-317  
  Keywords Human Health  
  Abstract Short-wavelength and short-wavelength-enhanced light have a strong impact on night-time working performance, subjective feelings of alertness and circadian physiology. In the present study, we investigated acute effects of white light sources with varied reduced portions of short wavelengths on cognitive and visual performance, mood and cardiac output.Thirty-one healthy subjects were investigated in a balanced cross-over design under three light spectra in a simulated night-shift paradigm without circadian adaptation.Exposure to the light spectrum with the largest attenuation of short wavelengths reduced heart rate and increased vagal cardiac parameters during the night compared to the other two light spectra without deleterious effects on sustained attention, working memory and subjective alertness. In addition, colour discrimination capability was significantly decreased under this light source.To our knowledge, the present study for the first time demonstrates that polychromatic white light with reduced short wavelengths, fulfilling current lighting standards for indoor illumination, may have a positive impact on cardiac physiology of night-shift workers without detrimental consequences for cognitive performance and alertness.  
  Address c Department of Psychology , University of Graz , Graz , Austria  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0742-0528 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:27579732 Approved no  
  Call Number LoNNe @ kyba @ Serial 1519  
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Author Chellappa, S.L.; Steiner, R.; Oelhafen, P.; Lang, D.; Gotz, T.; Krebs, J.; Cajochen, C. url  doi
openurl 
  Title (up) Acute exposure to evening blue-enriched light impacts on human sleep Type Journal Article
  Year 2013 Publication Journal of Sleep Research Abbreviated Journal J Sleep Res  
  Volume 22 Issue 5 Pages 573-580  
  Keywords Human Health  
  Abstract Light in the short wavelength range (blue light: 446-483 nm) elicits direct effects on human melatonin secretion, alertness and cognitive performance via non-image-forming photoreceptors. However, the impact of blue-enriched polychromatic light on human sleep architecture and sleep electroencephalographic activity remains fairly unknown. In this study we investigated sleep structure and sleep electroencephalographic characteristics of 30 healthy young participants (16 men, 14 women; age range 20-31 years) following 2 h of evening light exposure to polychromatic light at 6500 K, 2500 K and 3000 K. Sleep structure across the first three non-rapid eye movement non-rapid eye movement – rapid eye movement sleep cycles did not differ significantly with respect to the light conditions. All-night non-rapid eye movement sleep electroencephalographic power density indicated that exposure to light at 6500 K resulted in a tendency for less frontal non-rapid eye movement electroencephalographic power density, compared to light at 2500 K and 3000 K. The dynamics of non-rapid eye movement electroencephalographic slow wave activity (2.0-4.0 Hz), a functional index of homeostatic sleep pressure, were such that slow wave activity was reduced significantly during the first sleep cycle after light at 6500 K compared to light at 2500 K and 3000 K, particularly in the frontal derivation. Our data suggest that exposure to blue-enriched polychromatic light at relatively low room light levels impacts upon homeostatic sleep regulation, as indexed by reduction in frontal slow wave activity during the first non-rapid eye movement episode.  
  Address Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland; Cyclotron Research Center, University of Liege, Liege, Belgium  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-1105 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23509952 Approved no  
  Call Number GFZ @ kyba @ Serial 2201  
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Author Walker, W.H. 2nd; Borniger, J.C.; Gaudier-Diaz, M.M.; Hecmarie Melendez-Fernandez, O.; Pascoe, J.L.; Courtney DeVries, A.; Nelson, R.J. url  doi
openurl 
  Title (up) Acute exposure to low-level light at night is sufficient to induce neurological changes and depressive-like behavior Type Journal Article
  Year 2019 Publication Molecular Psychiatry Abbreviated Journal Mol Psychiatry  
  Volume Issue Pages s41380-019-0430-4  
  Keywords Human health; physiology; brain  
  Abstract The advent and wide-spread adoption of electric lighting over the past century has profoundly affected the circadian organization of physiology and behavior for many individuals in industrialized nations; electric lighting in homes, work environments, and public areas have extended daytime activities into the evening, thus, increasing night-time exposure to light. Although initially assumed to be innocuous, chronic exposure to light at night (LAN) is now associated with increased incidence of cancer, metabolic disorders, and affective problems in humans. However, little is known about potential acute effects of LAN. To determine whether acute exposure to low-level LAN alters brain function, adult male, and female mice were housed in either light days and dark nights (LD; 14 h of 150 lux:10 h of 0 lux) or light days and low level light at night (LAN; 14 h of 150 lux:10 h of 5 lux). Mice exposed to LAN on three consecutive nights increased depressive-like responses compared to mice housed in dark nights. In addition, female mice exposed to LAN increased central tendency in the open field. LAN was associated with reduced hippocampal vascular endothelial growth factor-A (VEGF-A) in both male and female mice, as well as increased VEGFR1 and interleukin-1beta mRNA expression in females, and reduced brain derived neurotrophic factor mRNA in males. Further, LAN significantly altered circadian rhythms (activity and temperature) and circadian gene expression in female and male mice, respectively. Altogether, this study demonstrates that acute exposure to LAN alters brain physiology and can be detrimental to well-being in otherwise healthy individuals.  
  Address Department of Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV, 26506, USA  
  Corporate Author Thesis  
  Publisher Nature Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1359-4184 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:31138889 Approved no  
  Call Number IDA @ john @ Serial 2509  
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