1
|
Bjerrum LB, Nordhus IH, Sørensen L, Wulff K, Bjorvatn B, Flo-Groeneboom E, Visted E. Acute Effects of Light during Daytime on Central Aspects of Attention and Affect:A Systematic Review. Biol Psychol 2024:108845. [PMID: 38981576 DOI: 10.1016/j.biopsycho.2024.108845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 06/29/2024] [Accepted: 07/02/2024] [Indexed: 07/11/2024]
Abstract
Light regulates both image- and various non-image forming responses in humans, including acute effects on attention and affect. To advance the understanding of light's immediate effects, this systematic review describes the acute effects of monochromatic/narrow bandwidth and polychromatic white light during daytime on distinct aspects of attention (alertness, sustained attention, working memory, attentional control and flexibility), and measures of affect (self-report measures, performance-based tests, psychophysiological measures) in healthy, adult human subjects. Original, peer-reviewed (quasi-) experimental studies published between 2000 and May 2024 were included according to predefined inclusion and exclusion criteria. Study quality was assessed, and results were synthesized across aspects of attention and affect and grouped according to light interventions; monochromatic/narrowband-width or polychromatic white light (regular white, bright white, and white with high correlated color temperature (CCT)). Results from included studies (n = 62) showed that alertness and working memory were most affected by light. Electroencephalographic markers of alertness improved the most with exposure to narrow bandwidth long-wavelength light, regular white, and white light with high CCT. Self-reported alertness and measures of working memory improved the most with bright white light. Results from studies testing the acute effects on sustained attention and attentional control and flexibility were inconclusive. Performance-based and psychophysiological measures of affect were only influenced by narrow bandwidth long-wavelength light. Polychromatic white light exerted mixed effects on self-reported affect. Studies were strongly heterogeneous in terms of light stimuli characteristics and reporting of light stimuli and control of variables influencing light's acute effects.
Collapse
Affiliation(s)
- Louise Bruland Bjerrum
- Department of Clinical Psychology, University of Bergen, Årstadveien 17, 5009 Bergen, Norway.
| | - Inger Hilde Nordhus
- Department of Clinical Psychology, University of Bergen, Årstadveien 17, 5009 Bergen, Norway
| | - Lin Sørensen
- Department of Biological and Medical Psychology, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
| | - Katharina Wulff
- Department of Radiation Sciences and Department of Molecular Biology, Umeå University,901 87 Umeå, Sweden; Wallenberg Center for Molecular Medicine, Umeå University, 901 87 Umeå, Sweden
| | - Bjørn Bjorvatn
- Department of Global Public Health and Primary Care, University of Bergen, Årstadveien 17, 5009 Bergen, Norway; Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Jonas Lies vei 71, 5053 Bergen, Norway
| | | | - Endre Visted
- Department of Clinical Psychology, University of Bergen, Årstadveien 17, 5009 Bergen, Norway
| |
Collapse
|
2
|
Vani V, Ojha P, Gadhvi MA, Dixit A. Attentional Correlates of Colored Lights: Considerations for Cognitive Testing. Neuroscience 2024; 543:83-89. [PMID: 38403240 DOI: 10.1016/j.neuroscience.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/05/2024] [Accepted: 02/12/2024] [Indexed: 02/27/2024]
Abstract
Attention, an important index of cognitive function, can be affected amidst colored lights. This work investigated the effects of colored lights on the performance in attention task. Participants (N = 42) performed in one, two, and three letter cancellation task (LCT) during four lighting conditions. The order of LCT and the colored light sessions were randomized. The performance in LCT was evaluated through % accuracy, % omission, and % error. A repeated measures ANOVA showed a statistically significant difference in % accuracy in one LCT (F(2.46, 100.8) = 24.45, p < 0.001), two LCT (F(2.57, 105.4) = 20.53, p < 0.001), and three LCT (F(2.66, 109.22) = 17.96, p < 0.001) among the four colored lights. In addition, % omission revealed a statistically significant difference in one LCT (F(2.46, 100.8) = 24.43, p < 0.001), two LCT (F(2.57, 105.4) = 20.57, p < 0.001), and three LCT (F(2.66, 109.16) = 18.21, p < 0.001) among the four lights. There was no statistically significant difference in % error in one LCT (F(2.05, 84.1) = 1.23, p = 0.3), two LCT (F(2.66, 109.06) = 0.62, p = 0.971), three LCT (F(2.62, 107.53) = 0.97, p = 0.4) among the four lighting conditions. Colored lights affect attention-related cognitive processing. The attentional correlates of white and red lights are more compared to green, and blue lights. Lighting condition should be an important consideration for cognitive testing, for designing workspaces, educational settings, and other environments where attention plays a crucial role.
Collapse
Affiliation(s)
- Vakode Vani
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Pooja Ojha
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India.
| | - Mahesh Arjundan Gadhvi
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Abhinav Dixit
- Department of Physiology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| |
Collapse
|
3
|
Spitschan M, Kervezee L, Lok R, McGlashan E, Najjar RP. ENLIGHT: A consensus checklist for reporting laboratory-based studies on the non-visual effects of light in humans. EBioMedicine 2023; 98:104889. [PMID: 38043137 PMCID: PMC10704221 DOI: 10.1016/j.ebiom.2023.104889] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 10/19/2023] [Accepted: 11/10/2023] [Indexed: 12/05/2023] Open
Abstract
BACKGROUND There is no consensus on reporting light characteristics in studies investigating non-visual responses to light. This project aimed to develop a reporting checklist for laboratory-based investigations on the impact of light on non-visual physiology. METHODS A four-step modified Delphi process (three questionnaire-based feedback rounds and one face-to-face group discussion) involving international experts was conducted to reach consensus on the items to be included in the checklist. Following the consensus process, the resulting checklist was tested in a pilot phase with independent experts. FINDINGS An initial list of 61 items related to reporting light-based interventions was condensed to a final checklist containing 25 items, based upon consensus among experts (final n = 60). Nine items were deemed necessary to report regardless of research question or context. A description of each item is provided in the accompanying Explanation and Elaboration (E&E) document. The independent pilot testing phase led to minor textual clarifications in the checklist and E&E document. INTERPRETATION The ENLIGHT Checklist is the first consensus-based checklist for documenting and reporting ocular light-based interventions for human studies. The implementation of the checklist will enhance the impact of light-based research by ensuring comprehensive documentation, enhancing reproducibility, and enabling data aggregation across studies. FUNDING Network of European Institutes for Advanced Study (NETIAS) Constructive Advanced Thinking (CAT) programme; Sir Henry Wellcome Postdoctoral Fellowship (Wellcome Trust, 204686/Z/16/Z); Netherlands Organisation for Health Research and Development VENI fellowship (2020-09150161910128); U.S. Department of Defense Grant (W81XWH-16-1-0223); National University of Singapore (NUHSRO/2022/038/Startup/08); and National Research Foundation Singapore (NRF2022-THE004-0002).
Collapse
Affiliation(s)
- Manuel Spitschan
- TUM School of Medicine & Health, Department of Health and Sport Sciences, Technical University of Munich, Munich, Germany; TUM Institute for Advanced Study (TUM-IAS), Technical University of Munich, Garching, Germany; Max Planck Institute for Biological Cybernetics, Max Planck Research Group Translational Sensory & Circadian Neuroscience, Tübingen, Germany; TUMCREATE, Singapore, Singapore.
| | - Laura Kervezee
- Laboratory for Neurophysiology, Department of Cellular and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands.
| | - Renske Lok
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, USA.
| | - Elise McGlashan
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia; School of Psychological Science and Turner Institute for Brain and Mental Health, Monash University, Melbourne, Australia.
| | - Raymond P Najjar
- Department of Ophthalmology and Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore; Center for Innovation & Precision Eye Health, National University of Singapore, Singapore, Singapore; Singapore Eye Research Institute, Singapore, Singapore; Ophthalmology and Visual Sciences Academic Clinical Programme, Duke-NUS Medical School, Singapore, Singapore.
| |
Collapse
|
4
|
Gobert F, Corneyllie A, Bastuji H, Berthomier C, Thevenet M, Abernot J, Raverot V, Dailler F, Guérin C, Gronfier C, Luauté J, Perrin F. Twenty-four-hour rhythmicities in disorders of consciousness are associated with a favourable outcome. Commun Biol 2023; 6:1213. [PMID: 38030756 PMCID: PMC10687012 DOI: 10.1038/s42003-023-05588-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 11/15/2023] [Indexed: 12/01/2023] Open
Abstract
Fluctuations of consciousness and their rhythmicities have been rarely studied in patients with a disorder of consciousness after acute brain injuries. 24-h assessment of brain (EEG), behaviour (eye-opening), and circadian (clock-controlled hormones secretion from urine) functions was performed in acute brain-injured patients. The distribution, long-term predictability, and rhythmicity (circadian/ultradian) of various EEG features were compared with the initial clinical status, the functional outcome, and the circadian rhythmicities of behaviour and clock-controlled hormones. Here we show that more physiological and favourable patterns of fluctuations are associated with a higher 24 h predictability and sharp up-and-down shape of EEG switches, reminiscent of the Flip-Flop model of sleep. Multimodal rhythmic analysis shows that patients with simultaneous circadian rhythmicity for brain, behaviour, and hormones had a favourable outcome. Finally, both re-emerging EEG fluctuations and homogeneous 24-h cycles for EEG, eye-opening, and hormones appeared as surrogates for preserved functionality in brainstem and basal forebrain, which are key prognostic factors for later improvement. While the recovery of consciousness has previously been related to a high short-term complexity, we suggest in this exploratory study the importance of the high predictability of the 24 h long-term generation of brain rhythms and highlight the importance of circadian body-brain rhythms in awakening.
Collapse
Affiliation(s)
- Florent Gobert
- Neuro-Intensive care unit, Hospices Civils de Lyon, Neurological hospital Pierre-Wertheimer, 59 Boulevard Pinel, Bron, France.
- Trajectoires Team, Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), Bâtiment Inserm 16 avenue Doyen Lépine, Bron, France.
- CAP Team (Cognition Auditive et Psychoacoustique), Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 95 boulevard Pinel, Bron, France.
| | - Alexandra Corneyllie
- CAP Team (Cognition Auditive et Psychoacoustique), Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 95 boulevard Pinel, Bron, France
| | - Hélène Bastuji
- Sleep medicine centre, Hospices Civils de Lyon, Bron, F-69677, France
- Neuropain Team, Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 59 Boulevard Pinel, Bron, France
| | | | - Marc Thevenet
- CAP Team (Cognition Auditive et Psychoacoustique), Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 95 boulevard Pinel, Bron, France
| | - Jonas Abernot
- CAP Team (Cognition Auditive et Psychoacoustique), Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 95 boulevard Pinel, Bron, France
| | - Véronique Raverot
- Hormone Laboratory, Hospices Civils de Lyon, Neurological hospital Pierre-Wertheimer, 59 Boulevard Pinel, Bron, France
| | - Frédéric Dailler
- Neuro-Intensive care unit, Hospices Civils de Lyon, Neurological hospital Pierre-Wertheimer, 59 Boulevard Pinel, Bron, France
| | - Claude Guérin
- Intensive care unit, Hospices Civils de Lyon, Croix-Rousse hospital, 103 Grande-Rue de la Croix-Rousse, Lyon, France
- Intensive care unit, Hospices Civils de Lyon, Édouard Herriot hospital, 5 Place d'Arsonval, 69003, Lyon, France
| | - Claude Gronfier
- Waking team (Integrative Physiology of the Brain Arousal Systems), Lyon Neuroscience Research Centre, INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Jacques Luauté
- Trajectoires Team, Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), Bâtiment Inserm 16 avenue Doyen Lépine, Bron, France
- Neuro-rehabilitation unit, Hospices Civils de Lyon, Neurological hospital Pierre-Wertheimer, 59 Boulevard Pinel, Bron, France
| | - Fabien Perrin
- CAP Team (Cognition Auditive et Psychoacoustique), Lyon Neuroscience Research Centre (Université Claude Bernard Lyon 1, INSERM U1028, CNRS UMR5292), 95 boulevard Pinel, Bron, France
| |
Collapse
|
5
|
Beckers E, Campbell I, Sharifpour R, Paparella I, Berger A, Aizpurua JFB, Koshmanova E, Mortazavi N, Talwar P, Sherif S, Jacobs HIL, Vandewalle G. Impact of repeated short light exposures on sustained pupil responses in an fMRI environment. J Sleep Res 2023:e14085. [PMID: 37904313 DOI: 10.1111/jsr.14085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 09/05/2023] [Accepted: 10/15/2023] [Indexed: 11/01/2023]
Abstract
Light triggers numerous non-image-forming, or non-visual, biological effects. The brain correlates of these non-image-forming effects have been investigated, notably using magnetic resonance imaging and short light exposures varying in irradiance and spectral quality. However, it is not clear whether non-image-forming responses estimation may be biased by having light in sequential blocks, for example, through a potential carryover effect of one light onto the next. We reasoned that pupil light reflex was an easy readout of one of the non-image-forming effects of light that could be used to address this issue. We characterised the sustained pupil light reflex in 13-16 healthy young individuals under short light exposures during three distinct cognitive processes (executive, emotional and attentional). Light conditions pseudo-randomly alternated between monochromatic orange light (0.16 melanopic equivalent daylight illuminance lux) and polychromatic blue-enriched white light of three different levels (37, 92, 190 melanopic equivalent daylight illuminance lux). As expected, higher melanopic irradiance was associated with larger sustained pupil light reflex in each cognitive domain. This result was stable over the light sequence under higher melanopic irradiance levels compared with lower ones. Exploratory frequency-domain analyses further revealed that sustained pupil light reflex was more variable under lower melanopic irradiance levels. Importantly, sustained pupil light reflex varied across tasks independently of the light condition, pointing to a potential impact of light history and/or cognitive context on sustained pupil light reflex. Together, our results emphasise that the distinct contribution and adaptation of the different retinal photoreceptors influence the non-image-forming effects of light and therefore potentially their brain correlates.
Collapse
Affiliation(s)
- Elise Beckers
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, the Netherlands
| | - Islay Campbell
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Roya Sharifpour
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Ilenia Paparella
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Alexandre Berger
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
- Institute of Neuroscience (IoNS), Université Catholique de Louvain (UCLouvain), Woluwe-Saint-Lambert, Belgium
- Synergia Medical SA, Mont-Saint-Guibert, Belgium
| | | | - Ekaterina Koshmanova
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Nasrin Mortazavi
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Puneet Talwar
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Siya Sherif
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Heidi I L Jacobs
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, the Netherlands
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Gilles Vandewalle
- GIGA-Cyclotron Research Centre-In Vivo Imaging, University of Liège, Liège, Belgium
| |
Collapse
|
6
|
Jeong H, Kurihara T, Jiang X, Kondo S, Ueno Y, Hayashi Y, Lee D, Ikeda SI, Mori K, Torii H, Negishi K, Tsubota K. Suppressive effects of violet light transmission on myopia progression in a mouse model of lens-induced myopia. Exp Eye Res 2023; 228:109414. [PMID: 36764596 DOI: 10.1016/j.exer.2023.109414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 01/24/2023] [Accepted: 02/07/2023] [Indexed: 02/11/2023]
Abstract
The prevalence of myopia has been steadily increasing for several decades, and this condition can cause extensive medical and economic issues in society. Exposure to violet light (VL), a short wavelength (360-400 nm) of visible light from sunlight, has been suggested as an effective preventive and suppressive treatments for the development and progression of myopia. However, the clinical application of VL remains unclear. In this study, we aimed to investigate the preventive and suppressive effects of VL on myopia progression. Various transmittances of VL (40%, 70%, and 100%) were tested in C57BL/6J mice with lens-induced myopia (LIM). Changes in the refractive error, axial length, and choroid thickness during the 3-week LIM were measured. The myopic shift in refractive error and difference in axial length between the 0 and -30 diopter lens was lessened in a transmission-dependent manner. Choroidal thinning, which was observed in myopic conditions, was suppressed by VL exposure and affected by its transmission. The results suggest that myopia progression can be managed using VL transmittance. Therefore, these factors should be considered for the prevention and treatment of myopia.
Collapse
Affiliation(s)
- Heonuk Jeong
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Toshihide Kurihara
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
| | - Xiaoyan Jiang
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Shinichiro Kondo
- Tsubota Laboratory, Inc., 34 Shinanomachi, 304 Toshin Shinanomachi Ekimae Building, Shinjuku-ku, Tokyo, 160-0016, Japan
| | - Yusuke Ueno
- Menicon Co., Ltd., 21-19, Aoi 3, Naka-ku, Nagoya, 460-0006, Japan
| | - Yuki Hayashi
- Menicon Co., Ltd., 21-19, Aoi 3, Naka-ku, Nagoya, 460-0006, Japan
| | - Deokho Lee
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Shin-Ichi Ikeda
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kiwako Mori
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hidemasa Torii
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Tsubota Laboratory, Inc., 34 Shinanomachi, 304 Toshin Shinanomachi Ekimae Building, Shinjuku-ku, Tokyo, 160-0016, Japan.
| |
Collapse
|
7
|
Esposito T, Houser K. Correlated color temperature is not a suitable proxy for the biological potency of light. Sci Rep 2022; 12:20223. [PMID: 36418869 PMCID: PMC9684473 DOI: 10.1038/s41598-022-21755-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 09/30/2022] [Indexed: 11/25/2022] Open
Abstract
Using a simulation based on a real, five-channel tunable LED lighting system, we show that Correlated Color Temperature (CCT) is not a reasonable predictor of the biological potency of light, whether characterized with CIE melanopic Equivalent Daylight Illuminance (mel-EDI), Equivalent Melanopic Lux (EML) (a scalar multiple of mel-EDI), or Circadian Stimulus (CS). At a photopic corneal illuminance of 300 lx and Rf ≥ 70, spectra can vary in CS from 17 to 41% across CCTs from 2500 to 6000 K, and up to 23% at a single CCT, due to the choice of spectrum alone. The CS range is largest, and notably discontinuous, at a CCT of 3500 K, the location of the inflection point of the CS model. At a photopic corneal illuminance of 300 lx and Rf ≥ 70, mel-EDI can vary from 123 to 354 lx across CCTs from 2500 to 6000 K and can vary by up to 123 lx at a fixed CCT (e.g., 196 to 319 lx at 5000 K). The range of achievable mel-EDI increases as CCT increases and, on average, decreases as color fidelity, characterized with IES TM-30 Rf, increases. These data demonstrate that there is no easy mathematical conversion between CS and mel-EDI when a spectrally diverse spectra set of spectral power distributions is considered.
Collapse
Affiliation(s)
- Tony Esposito
- Lighting Research Solutions LLC, Philadelphia, PA, USA.
| | - Kevin Houser
- School of Civil and Construction Engineering, Oregon State University, Corvallis, OR, USA
- Pacific Northwest National Laboratory, Portland, OR, USA
| |
Collapse
|
8
|
Danilenko KV. Objective Measures of Immediate “Energizing” Effect of Light: Studies Review and Data Analysis. Clocks Sleep 2022; 4:475-496. [PMID: 36278531 PMCID: PMC9589941 DOI: 10.3390/clockssleep4040038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/18/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
While the energizing effect of light has been known since the early years of light therapy, its reliable detection using objective measures is still not well-established. This review aims to ascertain the immediate energizing effect of light and determine its best indicators. Sixty-four articles published before July 2022 were included in the review. The articles described 72 (sub-)studies performed in healthy individuals. Fourteen measures were analyzed. The analysis showed that light causes an energizing effect that can be best documented by measuring core (rectal) body temperature: the proportion of the studies revealing increasing, unchanging, and decreasing rectal temperature was 13/6/1. The second most suitable indicator was heart rate (10/22/1), which showed concordant changes with rectal temperature (a trend, seven mutual studies). There is no evidence from the reviewed articles that oxygen consumption, skin conductance, blood pressure, heart rate variability, non-rectal inner temperature (combined digestive, tympanic, and oral), skin temperature, or cortisol levels can provide light effect detection. Four other measures were found to be unsuitable as well but with less certainty due to the low number of studies (≤3): skin blood flow, noradrenaline, salivary alpha-amylase, and thyroid-stimulating hormone levels. On the other hand, light exposure had a noticeable effect on sympathetic nerve activity measured using microneurography; however, this measure can be accepted as a marker only tentatively as it was employed in a single study. The analysis took into account three factors—study limitation in design/analysis, use of light in day- or nighttime, and relative brightness of the light stimulus—that were found to significantly influence some of the analyzed variables. The review indicates that the energizing effect of light in humans can be reliably detected using rectal temperature and heart rate.
Collapse
|
9
|
Polese D, Riccio ML, Fagioli M, Mazzetta A, Fagioli F, Parisi P, Fagioli M. The Newborn's Reaction to Light as the Determinant of the Brain's Activation at Human Birth. Front Integr Neurosci 2022; 16:933426. [PMID: 36118115 PMCID: PMC9478760 DOI: 10.3389/fnint.2022.933426] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/16/2022] [Indexed: 11/13/2022] Open
Abstract
Developmental neuroscience research has not yet fully unveiled the dynamics involved in human birth. The trigger of the first breath, often assumed to be the marker of human life, has not been characterized nor has the process entailing brain modification and activation at birth been clarified yet. To date, few researchers only have investigated the impact of the extrauterine environment, with its strong stimuli, on birth. This ‘hypothesis and theory' article assumes the role of a specific stimulus activating the central nervous system (CNS) at human birth. This stimulus must have specific features though, such as novelty, efficacy, ubiquity, and immediacy. We propose light as a robust candidate for the CNS activation via the retina. Available data on fetal and neonatal neurodevelopment, in particular with reference to retinal light-responsive pathways, will be examined together with the GABA functional switch, and the subplate disappearance, which, at an experimental level, differentiate the neonatal brain from the fetal brain. In this study, we assume how a very rapid activation of retinal photoreceptors at birth initiates a sudden brain shift from the prenatal pattern of functions to the neonatal setup. Our assumption implies the presence of a photoreceptor capable of capturing and transducing light/photon stimulus, transforming it into an effective signal for the activation of new brain functions at birth. Opsin photoreception or, more specifically, melanopsin-dependent photoreception, which is provided by intrinsically photosensitive retinal ganglion cells (ipRGCs), is considered as a valid candidate. Although what is assumed herein cannot be verified in humans based on knowledge available so far, proposing an important and novel function can trigger a broad range of diversified research in different domains, from neurophysiology to neurology and psychiatry.
Collapse
Affiliation(s)
- Daniela Polese
- PhD Program on Sensorineural Plasticity, Department of Neuroscience, Mental Health and Sensory Organs NESMOS, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
- *Correspondence: Daniela Polese
| | | | - Marcella Fagioli
- Department of Mental Health, National Health System ASL Rome 1, Rome, Italy
| | - Alessandro Mazzetta
- PhD Program on Neuroscience, Department of Systems Medicine, Tor Vergata University, Rome, Italy
| | - Francesca Fagioli
- Department of Mental Health, National Health System ASL Rome 1, Rome, Italy
| | - Pasquale Parisi
- Chair of Pediatrics, Department of Neuroscience, Mental Health and Sensory Organs NESMOS, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | | |
Collapse
|
10
|
|
11
|
Luo X, Ru T, Chen Q, Hsiao FC, Hung CS, Yang CM, Zhou G. Temporal Dynamics of Subjective and Objective Alertness During Exposure to Bright Light in the Afternoon for 5 h. Front Physiol 2021; 12:771605. [PMID: 34950050 PMCID: PMC8691749 DOI: 10.3389/fphys.2021.771605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/08/2021] [Indexed: 11/22/2022] Open
Abstract
Light can induce an alertness response in humans. The effects of exposure to bright light vs. dim light on the levels of alertness during the day, especially in the afternoon, as reported in the literature, are inconsistent. This study employed a multiple measurement strategy to explore the temporal variations in the effects of exposure to bright light vs. regular office light (1,200 lx vs. 200 lx at eye level, 6,500 K) on the alertness of participants for 5 h in the afternoon. In this study, 20 healthy adults (11 female; mean age 23.25 ± 2.3 years) underwent the Karolinska sleepiness scale (KSS), the auditory psychomotor vigilance test (PVT), and the waking electroencephalogram (EEG) test for two levels of light intervention. The results yielded a relatively lower relative delta power and a relatively higher beta power for the 1,200 lx condition in comparison with the 200 lx condition. However, the light conditions elicited no statistically significant differences in the KSS scores and performance with respect to the PVT. The results suggested that exposure to bright light for 5 h in the afternoon could enhance physiological arousal while exerting insignificant effects on subjective feelings and performance abilities relating to the alertness of the participants.
Collapse
Affiliation(s)
- Xue Luo
- School of Psychology, South China Normal University, Guangzhou, China
| | - Taotao Ru
- Lab of Light and Physiopsychological Health, National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays, South China Normal University, South China Academy of Advanced Optoelectronics, Guangzhou, China
| | - Qingwei Chen
- Lab of Light and Physiopsychological Health, National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays, South China Normal University, South China Academy of Advanced Optoelectronics, Guangzhou, China
| | - Fan-Chi Hsiao
- Department of Counseling and Industrial/Organizational Psychology, Ming Chuan University, Taoyuan, Taiwan
| | - Ching-Sui Hung
- Department of Psychology, National Chengchi University, Taipei, Taiwan
| | - Chien-Ming Yang
- Department of Psychology, National Chengchi University, Taipei, Taiwan.,The Research Center for Mind, Brain, and Learning, National Chengchi University, Taipei, Taiwan
| | - Guofu Zhou
- Lab of Light and Physiopsychological Health, National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays, South China Normal University, South China Academy of Advanced Optoelectronics, Guangzhou, China
| |
Collapse
|
12
|
Yu H, Wang Q, Wu W, Zeng W, Feng Y. Therapeutic Effects of Melatonin on Ocular Diseases: Knowledge Map and Perspective. Front Pharmacol 2021; 12:721869. [PMID: 34795578 PMCID: PMC8593251 DOI: 10.3389/fphar.2021.721869] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/30/2021] [Indexed: 01/08/2023] Open
Abstract
Melatonin plays a critical role in the pathophysiological process including circadian rhythm, apoptosis, and oxidative stress. It can be synthesized in ocular tissues, and its receptors are also found in the eye, triggering more investigations concentrated on the role of melatonin in the eye. In the past decades, the protective and therapeutic potentials of melatonin for ocular diseases have been widely revealed in animal models. Herein, we construct a knowledge map of melatonin in treating ocular diseases through bibliometric analysis and review its current understanding and clinical evidence. The overall field could be divided into twelve topics through keywords co-occurrence analysis, in which the glaucoma, myopia, and retinal diseases were of greatest research interests according to the keywords burst detection. The existing clinical trials of melatonin in ocular diseases mainly focused on the glaucoma, and more research should be promoted, especially for various diseases and drug administration. We also discuss its bioavailability and further research topics including developing melatonin sensors for personalized medication, acting as stem cell therapy assistant drug, and consuming food-derived melatonin for facilitating its clinical transformation.
Collapse
Affiliation(s)
- Haozhe Yu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China.,Institute of Medical Technology, Peking University Health Science Center, Beijing, China
| | - Qicong Wang
- Department of Chinese Medicine of Taiwan, Hong Kong and Macao, Beijing University of Chinese Medicine, Beijing, China
| | - Wenyu Wu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Weizhen Zeng
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Yun Feng
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China.,Institute of Medical Technology, Peking University Health Science Center, Beijing, China
| |
Collapse
|
13
|
Taillard J, Gronfier C, Bioulac S, Philip P, Sagaspe P. Sleep in Normal Aging, Homeostatic and Circadian Regulation and Vulnerability to Sleep Deprivation. Brain Sci 2021; 11:1003. [PMID: 34439622 PMCID: PMC8392749 DOI: 10.3390/brainsci11081003] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/23/2021] [Accepted: 07/25/2021] [Indexed: 12/30/2022] Open
Abstract
In the context of geriatric research, a growing body of evidence links normal age-related changes in sleep with many adverse health outcomes, especially a decline in cognition in older adults. The most important sleep alterations that continue to worsen after 60 years involve sleep timing, (especially early wake time, phase advance), sleep maintenance (continuity of sleep interrupted by numerous awakenings) and reduced amount of sigma activity (during non-rapid eye movement (NREM) sleep) associated with modifications of sleep spindle characteristics (density, amplitude, frequency) and spindle-Slow Wave coupling. After 60 years, there is a very clear gender-dependent deterioration in sleep. Even if there are degradations of sleep after 60 years, daytime wake level and especially daytime sleepiness is not modified with age. On the other hand, under sleep deprivation condition, older adults show smaller cognitive impairments than younger adults, suggesting an age-related lower vulnerability to extended wakefulness. These sleep and cognitive age-related modifications would be due to a reduced homeostatic drive and consequently a reduced sleep need, an attenuation of circadian drive (reduction of sleep forbidden zone in late afternoon and wake forbidden zone in early morning), a modification of the interaction of the circadian and homeostatic processes and/or an alteration of subcortical structures involved in generation of circadian and homeostatic drive, or connections to the cerebral cortex with age. The modifications and interactions of these two processes with age are still uncertain, and still require further investigation. The understanding of the respective contribution of circadian and homeostatic processes in the regulation of neurobehavioral function with aging present a challenge for improving health, management of cognitive decline and potential early chronobiological or sleep-wake interventions.
Collapse
Affiliation(s)
- Jacques Taillard
- Sommeil, Addiction et Neuropsychiatrie, Université de Bordeaux, SANPSY, USR 3413, F-33000 Bordeaux, France; (S.B.); (P.P.); (P.S.)
- CNRS, SANPSY, USR 3413, F-33000 Bordeaux, France
| | - Claude Gronfier
- Lyon Neuroscience Research Center (CRNL), Integrative Physiology of the Brain Arousal Systems (Waking) Team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, F-69000 Lyon, France;
| | - Stéphanie Bioulac
- Sommeil, Addiction et Neuropsychiatrie, Université de Bordeaux, SANPSY, USR 3413, F-33000 Bordeaux, France; (S.B.); (P.P.); (P.S.)
- CNRS, SANPSY, USR 3413, F-33000 Bordeaux, France
- Pôle Neurosciences Cliniques, CHU de Bordeaux, F-33076 Bordeaux, France
| | - Pierre Philip
- Sommeil, Addiction et Neuropsychiatrie, Université de Bordeaux, SANPSY, USR 3413, F-33000 Bordeaux, France; (S.B.); (P.P.); (P.S.)
- CNRS, SANPSY, USR 3413, F-33000 Bordeaux, France
- Pôle Neurosciences Cliniques, CHU de Bordeaux, F-33076 Bordeaux, France
| | - Patricia Sagaspe
- Sommeil, Addiction et Neuropsychiatrie, Université de Bordeaux, SANPSY, USR 3413, F-33000 Bordeaux, France; (S.B.); (P.P.); (P.S.)
- CNRS, SANPSY, USR 3413, F-33000 Bordeaux, France
- Pôle Neurosciences Cliniques, CHU de Bordeaux, F-33076 Bordeaux, France
| |
Collapse
|
14
|
Spitschan M, Garbazza C, Kohl S, Cajochen C. Sleep and circadian phenotype in people without cone-mediated vision: a case series of five CNGB3 and two CNGA3 patients. Brain Commun 2021; 3:fcab159. [PMID: 34447932 PMCID: PMC8385249 DOI: 10.1093/braincomms/fcab159] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/14/2021] [Indexed: 01/28/2023] Open
Abstract
Light exposure entrains the circadian clock through the intrinsically photosensitive retinal ganglion cells, which sense light in addition to the cone and rod photoreceptors. In congenital achromatopsia (prevalence 1:30-50 000), the cone system is non-functional, resulting in severe light avoidance and photophobia at daytime light levels. How this condition affects circadian and neuroendocrine responses to light is not known. In this case series of genetically confirmed congenital achromatopsia patients (n = 7; age 30-72 years; 6 women, 1 male), we examined survey-assessed sleep/circadian phenotype, self-reported visual function, sensitivity to light and use of spectral filters that modify chronic light exposure. In all but one patient, we measured rest-activity cycles using actigraphy over 3 weeks and measured the melatonin phase angle of entrainment using the dim-light melatonin onset. Owing to their light sensitivity, congenital achromatopsia patients used filters to reduce retinal illumination. Thus, congenital achromatopsia patients experienced severely attenuated light exposure. In aggregate, we found a tendency to a late chronotype. We found regular rest-activity patterns in all patients and normal phase angles of entrainment in participants with a measurable dim-light melatonin onset. Our results reveal that a functional cone system and exposure to daytime light intensities are not necessary for regular behavioural and hormonal entrainment, even when survey-assessed sleep and circadian phenotype indicated a tendency for a late chronotype and sleep problems in our congenital achromatopsia cohort.
Collapse
Affiliation(s)
- Manuel Spitschan
- Department of Experimental Psychology, University of Oxford, Oxford, OX2 6GG, UK
- Centre for Chronobiology, Psychiatry Hospital of the University of Basel (UPK), CH-4002 Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, CH-4055 Basel, Switzerland
| | - Corrado Garbazza
- Centre for Chronobiology, Psychiatry Hospital of the University of Basel (UPK), CH-4002 Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, CH-4055 Basel, Switzerland
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, D-72076 Tübingen, Germany
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatry Hospital of the University of Basel (UPK), CH-4002 Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, CH-4055 Basel, Switzerland
| |
Collapse
|
15
|
Arguelles-Prieto R, Madrid JA, Rol MA, Bonmati-Carrion MA. Correlated color temperature and light intensity: Complementary features in non-visual light field. PLoS One 2021; 16:e0254171. [PMID: 34252130 PMCID: PMC8274909 DOI: 10.1371/journal.pone.0254171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/22/2021] [Indexed: 02/05/2023] Open
Abstract
An appropriate exposure to the light-dark cycle, with high irradiances during the day and darkness during the night is essential to keep our physiology on time. However, considering the increasing exposure to artificial light at night and its potential harmful effects on health (i.e. chronodisruption and associated health conditions), it is essential to understand the non-visual effects of light in humans. Melatonin suppression is considered the gold standard for nocturnal light effects, and the activation of intrinsically photosensitive retinal ganglion cells (ipRGCs) through the assessment of pupillary light reflex (PLR) has been recently gaining attention. Also, some theoretical models for melatonin suppression and retinal photoreceptors activation have been proposed. Our aim in this study was to determine the influence of correlated color temperature (CCT) on melatonin suppression and PLR, considering two commercial light sources, as well as to explore the possible correlation between both processes. Also, the contribution of irradiance (associated to CCT) was explored through mathematical modelling on a wider range of light sources. For that, melatonin suppression and PLR were experimentally assessed on 16 healthy and young volunteers under two light conditions (warmer, CCT 3000 K; and cooler, CCT 5700 K, at ~5·1018 photons/cm2/sec). Our experimental results yielded greater post-stimulus constriction under the cooler (5700 K, 13.3 ± 1.9%) than under the warmer light (3000 K, 8.7 ± 1.2%) (p < 0.01), although no significant differences were found between both conditions in terms of melatonin suppression. Interestingly, we failed to demonstrate correlation between PLR and melatonin suppression. Although methodological limitations cannot be discarded, this could be due to the existence of different subpopulations of Type 1 ipRGCs differentially contributing to PLR and melatonin suppression, which opens the way for further research on ipRGCs projection in humans. The application of theoretical modelling suggested that CCT should not be considered separately from irradiance when designing nocturnal/diurnal illumination systems. Further experimental studies on wider ranges of CCTs and light intensities are needed to confirm these conclusions.
Collapse
Affiliation(s)
- Raquel Arguelles-Prieto
- Chronobiology Lab, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, Murcia, Spain
| | - Juan Antonio Madrid
- Chronobiology Lab, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, Murcia, Spain
- Ciber Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| | - Maria Angeles Rol
- Chronobiology Lab, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, Murcia, Spain
- Ciber Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| | - Maria Angeles Bonmati-Carrion
- Chronobiology Lab, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, Murcia, Spain
- Ciber Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| |
Collapse
|
16
|
Prayag AS, Münch M, Aeschbach D, Chellappa SL, Gronfier C. Reply to Bracke et al. Comment on "Prayag et al. Light Modulation of Human Clocks, Wake, and Sleep. Clocks&Sleep 2019, 1, 193-208". Clocks Sleep 2021; 3:398-402. [PMID: 34287255 PMCID: PMC8293177 DOI: 10.3390/clockssleep3030026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 06/07/2021] [Indexed: 02/08/2023] Open
Abstract
We thank Bracke and colleagues [...].
Collapse
Affiliation(s)
- Abhishek S. Prayag
- Lyon Neuroscience Research Center (CRNL), Waking Team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, 69000 Lyon, France;
| | - Mirjam Münch
- Centre for Public Health Research, Massey University, Wellington 6140, New Zealand;
| | - Daniel Aeschbach
- Department of Sleep and Human Factors Research, Institute of Aerospace Medicine, German Aerospace Center (DLR), 51170 Cologne, Germany;
- Faculty of Medicine, University of Bonn, 53127 Bonn, Germany
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA;
| | - Sarah L. Chellappa
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA;
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Claude Gronfier
- Lyon Neuroscience Research Center (CRNL), Waking Team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, 69000 Lyon, France;
| |
Collapse
|
17
|
Afraid of the dark: Light acutely suppresses activity in the human amygdala. PLoS One 2021; 16:e0252350. [PMID: 34133439 PMCID: PMC8208532 DOI: 10.1371/journal.pone.0252350] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 05/12/2021] [Indexed: 12/04/2022] Open
Abstract
Light improves mood. The amygdala plays a critical role in regulating emotion, including fear-related responses. In rodents the amygdala receives direct light input from the retina, and light may play a role in fear-related learning. A direct effect of light on the amygdala represents a plausible mechanism of action for light’s mood-elevating effects in humans. However, the effect of light on activity in the amygdala in humans is not well understood. We examined the effect of passive dim-to-moderate white light exposure on activation of the amygdala in healthy young adults using the BOLD fMRI response (3T Siemens scanner; n = 23). Participants were exposed to alternating 30s blocks of light (10 lux or 100 lux) and dark (<1 lux), with each light intensity being presented separately. Light, compared with dark, suppressed activity in the amygdala. Moderate light exposure resulted in greater suppression of amygdala activity than dim light. Furthermore, functional connectivity between the amygdala and ventro-medial prefrontal cortex was enhanced during light relative to dark. These effects may contribute to light’s mood-elevating effects, via a reduction in negative, fear-related affect and enhanced processing of negative emotion.
Collapse
|
18
|
Rayapoullé A, Gronfier C, Forhan A, Heude B, Charles MA, Plancoulaine S. Longitudinal association between sleep features and refractive errors in preschoolers from the EDEN birth-cohort. Sci Rep 2021; 11:9044. [PMID: 33907290 PMCID: PMC8079679 DOI: 10.1038/s41598-021-88756-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/13/2021] [Indexed: 11/09/2022] Open
Abstract
Refractive errors are common, especially in children and adolescents, leading to global health issues, academic implications and economic costs. Circadian rhythm and sleep habits may play a role. The study included 1130 children from the EDEN birth-cohort. Data were collected through parental questionnaires at age 2 and 5 for sleep duration and timing, and at age 5 for refractive error. At 5 years, 20.4% were prescribed glasses (2% for myopia, 11.9% for hyperopia and 6.8% for unknown reason). Children slept on average (SD) 11h05/night (± 30 min) and 10h49/night (± 48 min) at age 2 and 5, respectively. Average bedtime and midsleep was 8.36 pm (± 30 min), 2.06 am (± 36 min), and 8.54 pm (± 30 min), 2.06 am (± 24 min) at age 2 and 5, respectively. A U-shaped association was observed between sleep duration at age 2 and eyeglass prescription at age 5. Later midsleep and bedtime at age 2 were associated with an increased risk of eyeglass prescription at age 5. Associations became borderline significant after adjustment for confounding factors. Sleep duration and timing at age 2 were associated with subsequent refractive errors in preschoolers from general population. Sleep hygiene might be a target for refractive errors prevention.
Collapse
Affiliation(s)
- Alexis Rayapoullé
- CRESS, Inserm, INRAE, Université de Paris, 75004, Paris, France.,Hôpitaux de Paris, 3 rue Victoria, 75004, Paris, France
| | - Claude Gronfier
- Lyon Neuroscience Research Center (CRNL), Waking Team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, 69000, Lyon, France
| | - Anne Forhan
- CRESS, Inserm, INRAE, Université de Paris, 75004, Paris, France
| | - Barbara Heude
- CRESS, Inserm, INRAE, Université de Paris, 75004, Paris, France
| | | | | |
Collapse
|
19
|
Alzahrani HS, Khuu SK, Roy M. Modelling the effect of light through commercially available blue-blocking lenses on the human circadian system. Clin Exp Optom 2021; 105:275-280. [PMID: 33779493 DOI: 10.1080/08164622.2021.1898276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
CLINICAL RELEVANCE Wearing blue-blocking lenses (BBLs) in the evening hours may not be effective in improving sleep quality. Optometrists need to be informed in prescribing BBLs by highlighting the consequences of their wear to the circadian system. BACKGROUND Excessive exposure to artificial light, particularly at short wavelengths, during the evening, may disrupt normal nocturnal melatonin production, which is a natural process of the circadian rhythm and affect sleep quality. Current BBLs have been designed to limit blue-light exposure and may offer a means to minimise disruption to the circadian system. The purpose of this study was to evaluate the impact of BBLs on a normal sleep-wake circadian rhythm. METHODS Seven different commercial brands of BBLs (Crizal Prevencia, Smart Blue Filter, Blu-OLP, Blue Control, UV++Blue Control, SeeCoat Blue UV and Blue Guardian) and powers (+2.00 D, -2.00 D and Plano) were evaluated by quantifying the degree to which they reduce light radiation from lamps and electronic devices. In particular, the non-linear circadian index and the circadian stimulus was determined for various light sources to establish changes in melatonin production that occur while viewing through different BBLs. RESULTS A large difference was shown in the effectiveness of different BBL brands in reducing the spectral sensitivity of the circadian system. The BBL brand was shown to selectively affect the non-linear circadian index and circadian stimulus, particularly with those with transmittance profiles that block the most blue light having the lowest effect on the suppression of nocturnal melatonin secretion. CONCLUSION BBLs may not improve sleep quality, because they continue to allow the transmittance of blue light that may suppress nocturnal melatonin secretion and hence disrupt the normal sleep-wake circadian rhythm.
Collapse
Affiliation(s)
- Hind Saeed Alzahrani
- School of Optometry and Vision Science, The University of New South Wales, Sydney, Australia.,Department of Physics, Taif University, Ta'if, Saudi Arabia
| | - Sieu K Khuu
- School of Optometry and Vision Science, The University of New South Wales, Sydney, Australia
| | - Maitreyee Roy
- School of Optometry and Vision Science, The University of New South Wales, Sydney, Australia
| |
Collapse
|
20
|
Kompier ME, Smolders KCHJ, de Kort YAW. Abrupt light transitions in illuminance and correlated colour temperature result in different temporal dynamics and interindividual variability for sensation, comfort and alertness. PLoS One 2021; 16:e0243259. [PMID: 33750954 PMCID: PMC7984641 DOI: 10.1371/journal.pone.0243259] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/08/2021] [Indexed: 11/19/2022] Open
Abstract
Detailed insights in both visual effects of light and effects beyond vision due to manipulations in illuminance and correlated color temperature (CCT) are needed to optimize study protocols as well as to design light scenarios for practical applications. This study investigated temporal dynamics and interindividual variability in subjective evaluations of sensation, comfort and mood as well as subjective and objective measures of alertness, arousal and thermoregulation following abrupt transitions in illuminance and CCT in a mild cold environment. The results revealed that effects could be uniquely attributed to changes in illuminance or CCT. No interaction effects of illuminance and CCT were found for any of these markers. Responses to the abrupt transitions in illuminance and CCT always occurred immediately and exclusively amongst the subjective measures. Most of these responses diminished over time within the 45-minute light manipulation. In this period, no responses were found for objective measures of vigilance, arousal or thermoregulation. Significant interindividual variability occurred only in the visual comfort evaluation in response to changes in the intensity of the light. The results indicate that the design of dynamic light scenarios aimed to enhance human alertness and vitality requires tailoring to the individual to create visually comfortable environments.
Collapse
Affiliation(s)
- Maaike E. Kompier
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Karin C. H. J. Smolders
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Yvonne A. W. de Kort
- Human-Technology Interaction, School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, the Netherlands
| |
Collapse
|
21
|
The effects of short-term light exposure on subjective affect and comfort are dependent on the lighting time of day. Sci Rep 2021; 11:2604. [PMID: 33510187 PMCID: PMC7843969 DOI: 10.1038/s41598-021-81182-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 12/29/2020] [Indexed: 11/17/2022] Open
Abstract
Light, one of the key environmental components for both life and work, played significant role in subjective feelings (e.g. affect and comfort), but the exact effects and mechanisms were still to be determined. The present study screened thirty healthy adults (13 females, 22.45 ± 3.26 years) and examined subjective affect and comfort under short-term white lights with different combination of correlated color temperature (CCT) and illuminance at different times of day (e.g. morning, afternoon, and evening). Our results showed a significant interaction between illuminance level and time-of-day on subjective comfort. Participants felt more comfortable under 50 lx and 100 lx instead of 500 lx in the evening, and more comfortable under 500 lx in the morning and afternoon. In addition, a positive correlation between illuminance and comfort in the morning and a negative correlation between them in the evening were found. No significant effect of CCT on any subjective feeling was revealed. Our results necessitate the consideration of time-of-day in understanding lighting effects and application of healthy lighting in daily life.
Collapse
|
22
|
Houser KW, Esposito T. Human-Centric Lighting: Foundational Considerations and a Five-Step Design Process. Front Neurol 2021; 12:630553. [PMID: 33584531 PMCID: PMC7873560 DOI: 10.3389/fneur.2021.630553] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/06/2021] [Indexed: 12/22/2022] Open
Abstract
At its best, human-centric lighting considers the visual and non-visual effects of light in support of positive human outcomes. At its worst, it is a marketing phrase used to healthwash lighting products or lighting design solutions. There is no doubt that environmental lighting contributes to human health, but how might one practice human-centric lighting given both the credible potential and the implausible hype? Marketing literature is filled with promises. Technical lighting societies have summarized the science but have not yet offered design guidance. Meanwhile, designers are in the middle, attempting to distinguish credible knowledge from that which is dubious to make design decisions that affect people directly. This article is intended to: (1) empower the reader with fundamental understandings of ways in which light affects health; (2) provide a process for human-centric lighting design that can dovetail with the decision-making process that is already a part of a designer's workflow.
Collapse
Affiliation(s)
- Kevin W. Houser
- School of Civil and Construction Engineering, Oregon State University, Corvallis, OR, United States
- Advanced Lighting Team, Pacific Northwest National Laboratory, Portland, OR, United States
| | - Tony Esposito
- Lighting Research Solutions LLC, Cambridge, MA, United States
| |
Collapse
|
23
|
Zauner J, Plischke H, Stijnen H, Schwarz UT, Strasburger H. Influence of common lighting conditions and time-of-day on the effort-related cardiac response. PLoS One 2020; 15:e0239553. [PMID: 33027252 PMCID: PMC7540875 DOI: 10.1371/journal.pone.0239553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/08/2020] [Indexed: 11/18/2022] Open
Abstract
Melanopic stimuli trigger diverse non-image-forming effects. However, evidence of a melanopic contribution to acute effects on alertness and performance is inconclusive, especially under common lighting situations. Effects on cognitive performance are likely mediated by effort-related physiological changes. We assessed the acute effects of lighting in three scenarios, at two times of day, on effort-related changes to cardiac contraction as indexed by the cardiac pre-ejection period (PEP). In a within-subject design, twenty-seven participants performed a cognitive task thrice during a morning and a late-afternoon session. We set the lighting at 500 lux in all three lighting scenarios, measured horizontally at the desk level, but with 54 lux, 128 lux, or 241 lux melanopic equivalent daylight illuminance at the eye level. Impedance cardiography and electrocardiography measurements were used to calculate PEP, for the baseline and task period. A shorter PEP during the task represents a sympathetic heart activation and therefore increased effort. Data were analysed with linear mixed-effect models. PEP changes depended on both the light scene and time of day (p = 0.01 and p = 0.002, respectively). The highest change (sympathetic activation) occurred for the medium one of the three stimuli (128 lux) during the late-afternoon session. However, effect sizes for the singular effects were small, and only for the combined effect of light and time of day middle-sized. Performance scores or self-reported scores on alertness and task demand did not change with the light scene. In conclusion, participants reached the same performance most efficiently at both the highest and lowest melanopic setting, and during the morning session. The resulting U-shaped relation between melanopic stimulus intensity and PEP is likely not dependent solely on intrinsic ipRGC stimuli, and might be moderated by extrinsic cone input. Since lighting situations were modelled according to current integrative lighting strategies and real-life indoor light intensities, the result has implications for artificial lighting in a work environment.
Collapse
Affiliation(s)
- Johannes Zauner
- Munich University of Applied Sciences, Munich, Germany
- * E-mail:
| | | | - Hanna Stijnen
- Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| | - Ulrich T. Schwarz
- Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| | - Hans Strasburger
- Institute of Medical Psychology, Ludwig-Maximilians-Universität, Munich, Germany
| |
Collapse
|
24
|
Münch M, Wirz-Justice A, Brown SA, Kantermann T, Martiny K, Stefani O, Vetter C, Wright KP, Wulff K, Skene DJ. The Role of Daylight for Humans: Gaps in Current Knowledge. Clocks Sleep 2020; 2:61-85. [PMID: 33089192 PMCID: PMC7445840 DOI: 10.3390/clockssleep2010008] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/21/2020] [Indexed: 01/04/2023] Open
Abstract
Daylight stems solely from direct, scattered and reflected sunlight, and undergoes dynamic changes in irradiance and spectral power composition due to latitude, time of day, time of year and the nature of the physical environment (reflections, buildings and vegetation). Humans and their ancestors evolved under these natural day/night cycles over millions of years. Electric light, a relatively recent invention, interacts and competes with the natural light-dark cycle to impact human biology. What are the consequences of living in industrialised urban areas with much less daylight and more use of electric light, throughout the day (and at night), on general health and quality of life? In this workshop report, we have classified key gaps of knowledge in daylight research into three main groups: (I) uncertainty as to daylight quantity and quality needed for "optimal" physiological and psychological functioning, (II) lack of consensus on practical measurement and assessment methods and tools for monitoring real (day) light exposure across multiple time scales, and (III) insufficient integration and exchange of daylight knowledge bases from different disciplines. Crucial short and long-term objectives to fill these gaps are proposed.
Collapse
Affiliation(s)
- Mirjam Münch
- Sleep/Wake Research Centre, Massey University Wellington, Wellington 6021, New Zealand
| | - Anna Wirz-Justice
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, 4002 Basel, Switzerland; (A.W.-J.); (O.S.)
- Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, 4002 Basel, Switzerland
| | - Steven A. Brown
- Chronobiology and Sleep Research Group, Institute of Pharmacology and Toxicology, University of Zürich, 8057 Zürich, Switzerland;
| | - Thomas Kantermann
- Faculty for Health and Social Affairs, University of Applied Sciences for Economics and Management (FOM), 45141 Essen, Germany;
- SynOpus, 44789 Bochum, Germany
| | - Klaus Martiny
- Psychiatric Center Copenhagen, University of Copenhagen, Rigshospitalet, 2100 Copenhagen, Denmark;
| | - Oliver Stefani
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, 4002 Basel, Switzerland; (A.W.-J.); (O.S.)
- Transfaculty Research Platform Molecular and Cognitive Neurosciences (MCN), University of Basel, 4002 Basel, Switzerland
| | - Céline Vetter
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA; (C.V.); (K.P.W.J.)
| | - Kenneth P. Wright
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA; (C.V.); (K.P.W.J.)
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado, Aurora, CO 80045, USA
| | - Katharina Wulff
- Departments of Radiation Sciences and Molecular Biology, Umeå University, 901 87 Umeå, Sweden;
- Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, 901 87 Umeå, Sweden
| | - Debra J. Skene
- Chronobiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK;
| |
Collapse
|
25
|
Milosavljevic N. How Does Light Regulate Mood and Behavioral State? Clocks Sleep 2019; 1:319-331. [PMID: 33089172 PMCID: PMC7445808 DOI: 10.3390/clockssleep1030027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/05/2019] [Indexed: 01/21/2023] Open
Abstract
The idea that light affects mood and behavioral state is not new. However, not much is known about the particular mechanisms and circuits involved. To fully understand these, we need to know what properties of light are important for mediating changes in mood as well as what photoreceptors and pathways are responsible. Increasing evidence from both human and animal studies imply that a specialized class of retinal ganglion cells, intrinsically photosensitive retinal ganglion cells (ipRGCs), plays an important role in the light-regulated effects on mood and behavioral state, which is in line with their well-established roles in other non-visual responses (pupillary light reflex and circadian photoentrainment). This paper reviews our current understanding on the mechanisms and paths by which the light information modulates behavioral state and mood.
Collapse
Affiliation(s)
- Nina Milosavljevic
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PL, UK;
| |
Collapse
|
26
|
Spitschan M, Stefani O, Blattner P, Gronfier C, Lockley SW, Lucas RJ. How to Report Light Exposure in Human Chronobiology and Sleep Research Experiments. Clocks Sleep 2019; 1:280-289. [PMID: 31281903 PMCID: PMC6609447 DOI: 10.3390/clockssleep1030024] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 06/13/2019] [Indexed: 02/07/2023] Open
Abstract
Exposure to light has short- and long-term impacts on non-visual responses in humans. While many aspects related to non-visual light sensitivity have been characterised (such as the action spectrum for melatonin suppression), much remains to be elucidated. Here, we provide a set of minimum reporting guidelines for reporting the stimulus conditions involving light as an intervention in chronobiology, sleep research and environmental psychology experiments. Corresponding to the current state-of-the-art knowledge (June 2019), these are (i) measure and report the spectral power distribution of the acute stimulus from the observer's point of view; (ii) measure and report the spectral power distribution of the background light environment from the observer's point of view; (iii), make spectra available in tabulated form, (iv) report α-opic (ir)radiances and illuminance; (v) describe the timing properties of stimulus (duration and pattern); (vi) describe the spatial properties of stimulus (spatial arrangement and extent), and (vii) report measurement conditions and equipment. We supplement the minimum reporting guidelines with optional reporting suggestions and discuss limitations of the reporting scheme.
Collapse
Affiliation(s)
- Manuel Spitschan
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel (UPK), 4002 Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland
| | - Oliver Stefani
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel (UPK), 4002 Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland
| | - Peter Blattner
- Federal Institute of Metrology METAS, 3003 Bern-Wabern, Switzerland
| | - Claude Gronfier
- Lyon Neuroscience Research Center, Waking team, INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, F-69000 Lyon, France
| | - Steven W. Lockley
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, MA 02115, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
- Monash Institute of Cognitive and Clinical Neurosciences, School of Psychological Sciences, Monash University, 18 Innovation Walk, Clayton, VIC 3800, Australia
| | - Robert J. Lucas
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
| |
Collapse
|
27
|
Prayag AS, Najjar RP, Gronfier C. Melatonin suppression is exquisitely sensitive to light and primarily driven by melanopsin in humans. J Pineal Res 2019; 66:e12562. [PMID: 30697806 DOI: 10.1111/jpi.12562] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 01/01/2019] [Accepted: 01/19/2019] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Light elicits a range of non-visual responses in humans. Driven predominantly by intrinsically photosensitive retinal ganglion cells (ipRGCs), but also by rods and/or cones, these responses include melatonin suppression. A sigmoidal relationship has been established between melatonin suppression and light intensity; however, photoreceptoral involvement remains unclear. METHODS AND RESULTS In this study, we first modelled the relationships between alpha-opic illuminances and melatonin suppression using an extensive dataset by Brainard and colleagues. Our results show that (a) melatonin suppression is better predicted by melanopic illuminance compared to other alpha-opic illuminances, (b) melatonin suppression is predicted to occur at levels as low as ~1.5 melanopic lux (melanopsin-weighted irradiance 0.2 µW/cm2 ), (c) saturation occurs at 305 melanopic lux (melanopsin-weighted irradiance 36.6 µW/cm2 ). We then tested this melanopsin-weighted illuminance-response model derived from Brainard and colleagues' data and show that it predicts equally well melatonin suppression data from our laboratory, although obtained using different intensities and exposure duration. DISCUSSION Together, our findings suggest that melatonin suppression by monochromatic lights is predominantly driven by melanopsin and that it can be initiated at extremely low melanopic lux levels in experimental conditions. This emphasizes the concern of the non-visual impacts of low light intensities in lighting design and light-emitting devices.
Collapse
Affiliation(s)
- Abhishek S Prayag
- Lyon Neuroscience Research Center, Integrative Physiology of the Brain Arousal Systems, Waking team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, F-69000, Lyon, France
| | - Raymond P Najjar
- Department of Visual Neuroscience, Singapore Eye Research Institute, Singapore
- The Ophthalmology & Visual Sciences ACP, Duke-NUS Medical School, Singapore
| | - Claude Gronfier
- Lyon Neuroscience Research Center, Integrative Physiology of the Brain Arousal Systems, Waking team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, F-69000, Lyon, France
| |
Collapse
|
28
|
Abstract
Light, through its non-imaging forming effects, plays a dominant role on a myriad of physiological functions, including the human sleep–wake cycle. The non-image forming effects of light heavily rely on specific properties such as intensity, duration, timing, pattern, and wavelengths. Here, we address how specific properties of light influence sleep and wakefulness in humans through acute effects, e.g., on alertness, and/or effects on the circadian timing system. Of critical relevance, we discuss how different characteristics of light exposure across the 24-h day can lead to changes in sleep–wake timing, sleep propensity, sleep architecture, and sleep and wake electroencephalogram (EEG) power spectra. Ultimately, knowledge on how light affects sleep and wakefulness can improve light settings at home and at the workplace to improve health and well-being and optimize treatments of chronobiological disorders.
Collapse
|