Non-visual Biological Mechanism

  • Wout van Bommel


Daily (circadian) bodily rhythms, a fundamental property of human life, are synchronised by the natural 24-h dark-light rhythm. This entrainment by light is one of the non-visual biological effects of light. In particular, the rhythms of the hormones cortisol, supplying energy to the body, and melatonin, facilitating sleep, are important.

A relatively new type of photoreceptor discovered in 2002, the photosensitive retinal ganglion cell pRGC, connects with the suprachiasmatic nucleus SCN, a structure within the brain that acts as a master biological clock. The SCN, in its turn, has pathways to the pineal gland, where melatonin is produced, and to the adrenal cortex responsible for the production of cortisol.

Light may, apart from effects on circadian rhythms, also have direct, acute photobiological effects that influence alertness and performance.

The spectral sensitivity of the pRGCs, given by their photopigment melanopsin, is different from that of rods and the three types of cones. Its sensitivity peaks in the blue part of the wavelength range. Rods and cones have a neural connection with ganglion cells, and consequently their signals interplay with the signal obtained from the pRGC itself. Much of this neural wiring is as yet unknown. Primarily because of this, it is impossible to define a single spectral sensitivity function or action spectrum for all non-visual effects of light. The correlated colour temperature can be used only as a rough indication for the characterisation of the spectrum of lamps for non-visual biological use. The spectrally weighted irradiances for the five human photopigments (α-opic irradiances) are at this moment the best characterisation.


  1. Aschoff J (1954) Zeitgeber der tierischen Tagesperiodik. Naturwissenschaften 41:49–56ADSCrossRefGoogle Scholar
  2. Aschoff J (1965) Circadian rhythms in man—a self-sustained oscillator with an inherent frequency underlies human 24-hour periodicity. Science 148:1427–1432ADSCrossRefGoogle Scholar
  3. Aschoff J (1981) Handbook of behavioral neurobiology, Biological rhythms. Plenum Press, New YorkGoogle Scholar
  4. Atamian HS, Creux NM, Brown EA, Garner AG, Blackman BK, Harmer SL (2016) Circadian regulation of sunflower heliotropism, floral orientation, and pollinator visits. Science 353:587–590ADSCrossRefGoogle Scholar
  5. Bailes HJ, Lucas RJ (2013) Human melanopsin forms a pigment maximally sensitive to blue light (lambdamax {approx} 479 nm) supporting activation of Gq/11 and Gi/o signalling cascades. Proc R Soc B Biol Sci 280(1759):20122987CrossRefGoogle Scholar
  6. Balsalobre A, Brown SA, Marcacci L, Tronche F, Kellendonk C, Reichardt HM, Schütz G, Schible U (2000) Resetting of circadian time in peripheral tissues by glucocorticoid signalling. Science 289:2344–2347ADSCrossRefGoogle Scholar
  7. Bargiello TA, Jackson FR, Young MW (1984) Restoration of circadian behavioural rhythms by gene transfer in Drosophila. Nature 312:752–754ADSCrossRefGoogle Scholar
  8. Berson DM (2003) Strange vision: ganglion cells as circadian photoreceptors. Trends Neurosci 26:314–320CrossRefGoogle Scholar
  9. Berson DM, Dunn FA, Takao M (2002) Phototransduction by retinal ganglion cells that set the circadian clock. Science 295:1070–1073ADSCrossRefGoogle Scholar
  10. Boivin DB, Czeisler CA (1998) Resetting of circadian melatonin and cortisol rhythms in humans by ordinary room light. NeuroReport 9:779–782CrossRefGoogle Scholar
  11. Brainard GC, Hanifin JP (2004) The effects of light on human health and behavior: relevance to architectural lighting. In: CIE x027:2004 Proceedings of CIE symposium ’04 light and health: non-visual effects, pp 2–16Google Scholar
  12. Brainard GC, Hanifin JP, Greeson JM, Byrne B, Glickman G, Gerner E, Rollag MD (2001) Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor. J Neurosci 21(16):6405–6412CrossRefGoogle Scholar
  13. Broszio K, Knoop M, Niedling M, Völker S (2017) Effective radiant flux for non-image forming effects—is the illuminance and the melanopic irradiance at the eye really the right measure? In: Proceedings Lux Europe, Ljubljana, pp 18–20Google Scholar
  14. Brown SA, Fleury-Olela F, Nagoshi E, Hauser C, Juge C, Meier CA, Chicheportiche R, Dayer JM, Albrecht U, Schibler U (2005) The period length of fibroblast circadian gene expression varies widely among human individuals. PLoS Biol 3(10):e338CrossRefGoogle Scholar
  15. Cajochen C (2007) Alerting effects of light. Sleep Med Rev 11:453–464CrossRefGoogle Scholar
  16. Cassone VM, Speh JC, Card JP, Moore RY (1988) Comparative anatomy of the mammalian hypothalamic suprachiasmatic nucleus. J Biol Rhythms 3:71–91CrossRefGoogle Scholar
  17. Chang AM, Scheer FAJL, Czeisler CA (2011) The human circadian system adapts to prior photic history. J Physiol 589(5):1095–1102CrossRefGoogle Scholar
  18. Chellappa SL, Gordijn MCM, Cajochen C (2011) Can light make us bright? Effects of light on cognition sleep. In: Kerkhof G, van Dongen HPA (eds) Progress in brain research. Elsevier, Amsterdam, p 190Google Scholar
  19. Chen SK, Badea TC, Hattar S (2011) Photoentrainment and pupillary light reflex are mediated by distinct populations of ipRGCs. Nature 476:92–95CrossRefGoogle Scholar
  20. Chovnick A (1960) Proceedings of Cold Spring Harbor symposium on quantitative biology. In: Biological clocks 25:117–514Google Scholar
  21. CIE (2004) International Commission on Illumination CIE Publication 158:2004, Ocular lighting effects on human physiology and behaviour. ViennaGoogle Scholar
  22. CIE (2015a) International Commission on Illumination CIE Technical Note 003:2015, Report on the first international workshop on circadian and neurophysiological photometry, 2013. ViennaGoogle Scholar
  23. CIE (2015b) Irradiance toolbox.
  24. CIE (2016) International Commission on Illumination CIE DIS 017:2016 (term 17-29-030). CIE Draft international standard, ILV: International lighting vocabulary. ViennaGoogle Scholar
  25. CIE (2018) International Commission on Illumination CIE International Standard CIE 026:2018. CIE system for metrology of optical radiation for ipRGC-influenced responses to light. ViennaGoogle Scholar
  26. Czeisler CA, Duffy JF, Shanahan TL, Brown EN, Mitchell JF, Rimmer DW, Ronda JM, Silva EJ, Allan JS, Emens JS, Dijk DJ, Kronauer RE (1999) Stability, precision, and near-24-hour period of the human circadian pacemaker. Science 284(5423):2177–2181CrossRefGoogle Scholar
  27. Dacey DM, Liao HW, Peterson BB, Robinson FR, Smith VC, Pokorny J, Yau KW, Gamlin PD (2005) Melanopsin-expressing ganglion cells in primate retina signal colour and irradiance and project to the LGN. Nature 433(7027):749–754ADSCrossRefGoogle Scholar
  28. De Candolle A (1832) La Physiologie végégetal. Béchet Jeune, ParisGoogle Scholar
  29. De Mairan JJO (1729) Observation botanique. Hist. de l’Acad. Royal Sciences, Paris, p 1Google Scholar
  30. Dickmeis T (2009) Glucocorticoids and the circadian clock. J Endocrinol 200:3–22CrossRefGoogle Scholar
  31. Do MTH, Kang SH, Xue T, Zhong H, Liao HW, Bergles DE, Yau KW (2009) Photon capture and signalling by melanopsin retinal ganglion cells. Nature 457:281–287ADSCrossRefGoogle Scholar
  32. Duffy JF, Cain SW, Chang AM, Phillips AJK, Münch MY, Gronfier C, Wyatt JK, Dijk DJ, Wright KP, Czeisler CA (2011) Sex difference in the near-24-hour intrinsic period of the human circadian timing system. Proc Natl Acad Sci USA 108(Suppl 3):15602–15608ADSCrossRefGoogle Scholar
  33. Dunlap JC, Loros JJ, Aronson BD, Merrow M, Crosthwaite S, Bell-Pedersen D, Johnson K, Lindgren K, Garceau NY (1995) The genetic basis of the circadian clock identification of frq and FRQ as clock components. In: Circadian clocks and their adjustment, Ciba Foundation Symposium 183. Wiley, ChichesterGoogle Scholar
  34. Eastman CI, Burgess HJ (2009) How to travel the world without jet lag. Sleep Med Clin 4(2):241–255CrossRefGoogle Scholar
  35. Emery P, So WV, Kaneko M, Hall JC, Rosbach M (1998) CRY, a Drosophila clock and light-regulated cryptochrome, is a major contributor to circadian rhythm resetting and photosensitivity. Cell 95:669–679CrossRefGoogle Scholar
  36. Figueiro MG, Rea MS (2010) The effects of red and blue lights on circadian variations in cortisol, alpha amylase, and melatonin. Int J Endocrinol 2010:1–9CrossRefGoogle Scholar
  37. Figueiro MG, Rea MS, Bullough JD (2006) Circadian effectiveness of two polychromatic lights in suppressing human nocturnal melatonin. Neurosci Lett 406:293–297CrossRefGoogle Scholar
  38. Foster R, Kreitzman L (2004) Rhythms of life. The biological clocks that control the daily lives of every living thing. Profile Books Ltd., LondonGoogle Scholar
  39. Foster RG, Provencio I, Hudson D, Fiske S, De Grip W, Menaker M (1991) Circadian photoreception in the retinally degenerate mouse (rd/rd). J Comp Physiol A 169(1):39–50CrossRefGoogle Scholar
  40. Freedman MS, Lucas RJ, Soni B, von Schantz M, Munoz M, David-Gray Z, Foster R (1999) Regulation of mammalian circadian behavior by non-rod, non-cone, ocular photoreceptors. Science 284:502–504ADSCrossRefGoogle Scholar
  41. Gamlin PD, McDougal DH, Pokorny J, Smith VC, Yau KW, Dacey DM (2007) Human and macaque pupil responses driven by melanopsin-containing retinal ganglion cells. Vision Res 47(7):946–954CrossRefGoogle Scholar
  42. Giménez M, Schlangen L, Lang D, Beersma D, Novotny P, Plischke H, Wulff K, Linek M, Cajochen C, Löffler J, Lasauskaite R, Bhusal P, Halonen L (2016) D3.7 Report on metric to quantify biological light exposure doses. Accelerate SSL Innovation for Europe. SSL-erate ConsortiumGoogle Scholar
  43. Glickman G, Hanifin JP, Rollag MD, Wang H, Cooper H, Brainard GC (2003) Inferior retinal light exposure is more effective than superior retinal exposure in suppressing melatonin in humans. J Biol Rhythms 18:71–79CrossRefGoogle Scholar
  44. Gooley JJ, Lu J, Chou TC, Scammell TE, Saper CB (2001) Melanopsin in cells of origin of the retinohypothalamic tract. Nat Neurosci 4(12):1165CrossRefGoogle Scholar
  45. Hankins MW, Lucas RJ (2002) The primary visual pathway in humans is regulated according to long-term light exposure through the action of a nonclassical photopigment. Curr Biol 12(3):191–198CrossRefGoogle Scholar
  46. Hattar S, Liao HW, Takao M, Berson DM, Yau KW (2002) Melanopsin-containing retinal ganglion cells: architecture, projections, and intrinsic photosensitivity. Science 295:1065–1070ADSCrossRefGoogle Scholar
  47. Hattar S, Lucas RJ, Mrosovsky N, Thompson S, Douglas RH, Hankins MW, Lem J, Biel M, Hofmann F, Foster RG, Yau KW (2003) Melanopsin and rod–cone photoreceptive systems account for all major accessory visual functions in mice. Nature 424(6944):75–81ADSCrossRefGoogle Scholar
  48. Hébert M, Martin SK, Lee C, Eastman CI (2002) The effects of prior light history on the suppression of melatonin by light in humans. J Pineal Res 33(4):198–203CrossRefGoogle Scholar
  49. Hoyle NP, Seinkmane E, Putker M, Feeney KA, Krogager TP, Chesham JE, Bray LK, Thomas JM, Dunn K, Blaikley J, O’Neil JS (2017) Circadian actin dynamics drive rhythmic fibroblast mobilization during wound healing. Sci Transl Med 9(415):eaal2774CrossRefGoogle Scholar
  50. Jasser SA, Hanifin JP, Rollag MD, Brainard GC (2006) Dim light adaptation attenuates acute melatonin suppression in humans. J Biol Rhythms 21(5):394–404CrossRefGoogle Scholar
  51. Jones BE (2003) Arousal systems. Front Biosci 8:S438–S451CrossRefGoogle Scholar
  52. Kalsbeek A, Buijs RM (2002) Output pathways of the mammalian suprachiasmatic nucleus: coding circadian time by transmitter selection and specific targeting. Cell Tissue Res 309:109–118CrossRefGoogle Scholar
  53. Kaur G, Phillips C, Wong K, Saini B (2013) Timing is important in medication administration: a timely review of chronotherapy research. Int J Clin Pharm 35(3):344–358CrossRefGoogle Scholar
  54. Klein DC, Moore RY, Reppert SM (1991) Suprachiasmatic nucleus: the mind’s clock. Oxford University Press, OxfordGoogle Scholar
  55. Klerman EB, Rimmer DW, Dijk D-J, Kronauer RE, Rizzo JF III, Czeisler CA (1998) Nonphotic entrainment of the human circadian pacemaker. Am J Physiol 274:R991–R996Google Scholar
  56. Knoop M (2018) Opinion: studies on non-image forming effects—lighting cold cases? Lighting Res Technol 50:496CrossRefGoogle Scholar
  57. Kobav MB, Bizjak G (2012) LED spectra and melatonin suppression action function. Light Eng 20(3):15–22Google Scholar
  58. Kozaki T, Kubokawa A, Taketomi R, Hatae K (2016) Light-induced melatonin suppression at night after exposure to different wavelength composition of morning light. Neurosci Lett 616:1–4CrossRefGoogle Scholar
  59. Kumbalasiri T, Provencio I (2005) Melanopsin and other novel mammalian opsins. Exp Eye Res 81:368–375CrossRefGoogle Scholar
  60. Lasko TA, Kripke DF, Elliot JA (1999) Melatonin suppression by illumination of upper and lower visual fields. J Biol Rhythms 14:122–125CrossRefGoogle Scholar
  61. Lerner AB, Case JD, Takahashi Y, Lee TH, Mori W (1958) Isolation of melatonin, the pineal gland factor that lightens melanocytes. J Am Chem Soc 80(10):2587CrossRefGoogle Scholar
  62. Lockley SW, Evans EE, Scheer FAJL, Brainard GC, Czeisler CA et al (2006) Short-wavelength sensitivity for the direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans. Sleep 29:161–168Google Scholar
  63. Lowden A, Äkerstedt T, Wibom R (2004) Suppression of sleepiness and melatonin by bright light exposure during breaks in night work. J Sleep Res 13:37–43CrossRefGoogle Scholar
  64. Lucas RJ, Hattar S, Takao M, Berson DM, Foster RG, Yau KW (2003) Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice. Science 299(5604):245–247ADSCrossRefGoogle Scholar
  65. Lucas RJ, Peirson SN, Berson SN, Brown TM, Cooper HM, Czeisler CA, Figueiro MG, Gamlin PD, Lockley SW, O’Hagan JB, Price LLA, Provencio I, Skene DJ, Brainard GC (2014) Measuring and using light in the melanopsin age. Trends Neurosci 37(1):1–9CrossRefGoogle Scholar
  66. McIntyre IM, Norman TR, Burrows GD, Armstrong SM (1989a) Human melatonin suppression by light is intensity dependent. J Pineal Res 6(2):149–156CrossRefGoogle Scholar
  67. McIntyre IM, Norman TR, Burrows GD, Armstrong SM (1989b) Quantal melatonin suppression by exposure to low intensity light in man. Life Sci 45(4):327–332CrossRefGoogle Scholar
  68. Moore RY, Eichler VB (1972) Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat. Brain Res 42:201–206CrossRefGoogle Scholar
  69. Moore RY, Heller A, Wurtman RJ, Axelrod J (1967) Visual pathway mediating pineal response to environmental light. Science 155(3759):220–223ADSCrossRefGoogle Scholar
  70. Moore RY, Speh JC, Card JP (1995) The retinohypothalamic tract originates from a distinct subset of retinal ganglion cells. J Comp Neurol 352(3):351–366CrossRefGoogle Scholar
  71. Morin LP (1994) The circadian visual system. Brain Res Rev 19:102–127CrossRefGoogle Scholar
  72. Mure LS, Rieux C, Hattar S, Cooper HM (2007) Melanopsin-dependent nonvisual responses: evidence for photopigment bistability in vivo. J Biol Rhythms 5:411–424CrossRefGoogle Scholar
  73. Newman LA, Walker MT, Brown RL, Cronin TW, Robinson PR (2003) Melanopsin forms a functional short wavelength photopigment. Biochemistry 42:12734–12738CrossRefGoogle Scholar
  74. Panda S, Provencio I, Tu DC, Pires SS, Rollag MD, Castrucci AM, Pletcher MT, Sato TK, Wiltshire T, Andahazy M, Kay SA, Van Gelder RN, Hogenesch JB (2003) Melanopsin Is Required for Non-Image-Forming Photic Responses in Blind Mice. Science 301(5632):525–527ADSCrossRefGoogle Scholar
  75. Pauers MJ, Kuchenbecker JA, Neitz M, Neitz J (2012) Changes in the colour of light cue circadian activity. Anim Behav 83:1143–1151CrossRefGoogle Scholar
  76. Peirson S, Foster RG (2006) Melanopsin: another way of signalling light. Neuron 49(3):331–339CrossRefGoogle Scholar
  77. Phipps-Nelson J, Redman JR, Dijk DJ, Rajaratnam SM (2003) Daytime exposure to bright light, as compared to dim light, decreases sleepiness and improves psychomotor, vigilance performance. Sleep 26:695–700CrossRefGoogle Scholar
  78. Piazena H, Franke L, Thomsen B, Kamenzky I, Uebelhack R, Völker S (2014) Melatoninsuppression mit Weiβlicht-LEDs—erste Ergebnisse. In: Proceedings of the 8th symposium Licht und Gesundheit, Berlin, pp 39–52Google Scholar
  79. Pittendrigh CS, Bruce VG (1957) An oscillator model for biological clocks. In: Rudnick D (ed) Rhythmic and synthetic processes in growth. Princeton University Press, Princeton, NJ, pp 239–268Google Scholar
  80. Provencio I, Rodriguez IR, Jiang GS, Hayes WP, Moreira EF, Rollag MD (2000) A novel human opsin in the inner retina. J Neurosci 20:600–605CrossRefGoogle Scholar
  81. Rautkylä E, Puolakka M, Halonen L (2012) Alerting effects of daytime light exposure—a proposed link between light exposure and brain mechanisms. Lighting Res Technol 44:238–252CrossRefGoogle Scholar
  82. Rea MS (2002) Light—much more then vision. In: Light and human health: EPRI/LRO 5th international lighting research symposium, Palo Alto, pp 1–15Google Scholar
  83. Rea MS, Bullough JD, Figueiro MG, Bierman A (2004) Spectral opponency in human circadian phototransduction: implications for lighting practice. In: Proceedings of CIE symposium lighting & health, Vienna, pp 111–115Google Scholar
  84. Rea MS, Figueiro MG, Bullough JD, Bierman A (2005) A model of phototransduction by the human circadian system. Brain Res Rev 50:213–228CrossRefGoogle Scholar
  85. Rea MS, Figueiro MG, Bierman A, Bullough JD (2010) Circadian light. J Circ Rhythms 8(2):1–10Google Scholar
  86. Rea MS, Figueiro MG, Bierman A, Hamner MS (2012) Modelling the spectral sensitivity of the human circadian system. Lighting Res Technol 44:386–396CrossRefGoogle Scholar
  87. Refinetti R (2015) Comparison of light, food, and temperature as environmental synchronizers of the circadian rhythm of activity in mice. J Physiol Sci 65:359–366CrossRefGoogle Scholar
  88. Revell VL, Molina TA, Eastman CI (2012) Human phase response curve to intermittent blue light using a commercially available device. J Physiol 590(19):4859–4868CrossRefGoogle Scholar
  89. Richter C (1967) Psychopathology of periodic behavior in animals and man. In: Zubin J, Hunt HF (eds) Comparative psychopathology, vol 205. Grune & Stratton, New York, p 227Google Scholar
  90. Roenneberg T, Wirz-Justice A, Merrow M (2003) Life between clocks: daily temporal patterns of human chronotypes. J Biol Rhythms 18(1):80–90CrossRefGoogle Scholar
  91. Roenneberg T, Kuehnle T, Pramstaller PP, Ricken J, Havel M, Guth A, Merrow M (2004) A marker for the end of adolescence. Curr Biol 14:R1038-RCrossRefGoogle Scholar
  92. Roenneberg T, Kuehnle T, Juda M, Kantermann T, Allebrandt K, Gordijn M, Merrow M (2007) Epidemiology of the human circadian clock. Sleep Med Rev 11:429–438CrossRefGoogle Scholar
  93. Roenneberg T, Juda M, Kramer A, Merrow M, Vetter C, Allebrandt KV (2013) Light and the human circadian clock. In: Kramer A, Merrow M (eds) Circadian clocks. Springer, BerlinGoogle Scholar
  94. Rosenthal NE, Joseph-Vanderpool JR, Levendosky AA, Johnston SH, Allen R, Kelly KA, Souetre E, Schultz PM, Starz KE (1990) Phase-shifting effects of bright morning light as treatment for delayed sleep phase syndrome. Sleep 13(4):354–361Google Scholar
  95. Rüger M, Gordijn MCM, Beersma DGM, De Vries B, Daan S (2005) Nasal versus temporal illumination of the human retina: effects on core body temperature, melatonin and circadian phase. J Biol Rhythms 14:122–125Google Scholar
  96. Saper CB, Scammell TE, Lu J (2005) Hypothalamic regulation of sleep and circadian rhythms. Nature 437:1257–1263ADSCrossRefGoogle Scholar
  97. Stephan FK, Zucker I (1972) Circadian rhythm in drinking behavior and locomotor activity of rats are eliminated by hypothalamic lesions. Proc Natl Acad Sci USA 69:1583–1586ADSCrossRefGoogle Scholar
  98. Takahashi Y, Katsuura T, Shimomura Y, Iwanago K (2011) Prediction model of light-induced melatonin suppression. J Light Vis Environ 35(2):123–135ADSCrossRefGoogle Scholar
  99. Teclemariam-Mesbah R, Ter Horst GJ, Postema F, Wortel J, Buijs RM (1999) Anatomical demonstration of the suprachiasmatic nucleus–pineal pathway. J Comp Neurol 406:171–182CrossRefGoogle Scholar
  100. Terman M, Lewy AJ, Dijk DJ, Boulos Z, Eastman CI, Campbell SS (1995) Light treatment for sleep disorders: consensus report. IV. Sleep phase and duration disturbances. J Biol Rhythms 10(2):135–147CrossRefGoogle Scholar
  101. Thapan K, Arendt J, Skene DJ (2001) An action spectrum for melatonin suppression: evidence for a novel non-rod, non-cone photoreceptor system in humans. J Physiol 535(1):261–267CrossRefGoogle Scholar
  102. Thorn L, Hucklebridge F, Esgate A, Evans P, Clow A (2004) The effect of dawn simulation on the cortisol response to awakening in healthy participants. Psychoneuroendocrinology 29:925–930CrossRefGoogle Scholar
  103. Van Bommel WJM (2010) Incandescent replacement lamps and health. LED Prof Rev 19:32–35Google Scholar
  104. Van Diepen HC, Ramkisoensing A, Peirson SN, Foster RG, Meijer JH (2013) Irradiance encoding in the suprachiasmatic nuclei by rod and cone photoreceptors. FASEB J 27:4204–4212CrossRefGoogle Scholar
  105. Van Diepen HC, Foster RG, Meijer JH (2015) A colourful clock. PLoS Biol 1002160:1–5Google Scholar
  106. Van Gelder RN, Mawad K (2007) Illuminating the mysteries of melanopsin and circadian photoreception. J Biol Rhythms 5:394–395Google Scholar
  107. Vanderwalle G, Maquet P, Dijk DJ (2009) Light as a modulator of cognitive brain function. Trends Cogn Sci 13(10):429–438CrossRefGoogle Scholar
  108. Vandewalle G, Balteau E, Phillips C, Degueldre C, Moreau V, Sterpenich V, Albouy G, Darsaud A, Dessailles M, Dang-Vu TT, Peigneux P, Luxen A, Dijk DJ, Maquet P (2006) Daytime light exposure dynamically enhances brain responses. Curr Biol 16:1616–1621CrossRefGoogle Scholar
  109. Visser EK, Beersma DGM, Daan S (1999) Melatonin suppression by light in humans is maximal when the nasal part of the retina is illuminated. J Biol Rhythms 14:116–121CrossRefGoogle Scholar
  110. Walmsley L, Hanna L, Mouland J, Martial F, West A, Smedley AR, Bechtold DA, Webb AR, Lucas RJ, Brown TM (2015) Colour as signal for entraining the mammalian circadian clock. PLoS Biol 1002127:1–20Google Scholar
  111. Winget CM, Hughes L, LaDou J (1978) Physiological effects of rotational work shifting: a review. J Occup Med 20(3):204–210CrossRefGoogle Scholar
  112. Woelders T, Beersma DGM, Gordijn MCM, Hut RA, Wams EJ (2017) Daily light exposure patterns reveal phase and period of the human circadian clock. J Biol Rhythms 32(3):274–286CrossRefGoogle Scholar
  113. Xu W, Van Bommel WJM (2011) Inferior verso superior: inferior retinal light exposure is more effective in pupil contraction in humans. Light Eng 19(2):14–18Google Scholar
  114. Yamazaki S, Numano R, Abe M, Hida A, Takahashi R, Ueda M, Block GD, Sakaki Y, Menaker M, Tei H (2000) Resetting central and peripheral circadian oscillators in transgenic rats. Science 288:682–685ADSCrossRefGoogle Scholar
  115. Zeitzer JM, Friedman L, Yesavage JA (2011) Effectiveness of evening phototherapy for insomnia is reduced by bright daytime light exposure. Sleep Med 12(8):805–807CrossRefGoogle Scholar
  116. Zulley J, Knab B (2000) Unsere Innere Uhr. Herder, Freiburg im BreisgauGoogle Scholar

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Authors and Affiliations

  • Wout van Bommel
    • 1
  1. 1.Van Bommel Lighting ConsultantNuenenThe Netherlands

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