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. 2020 Aug 23:9:100055.
doi: 10.1016/j.nbscr.2020.100055. eCollection 2020 Nov.

Phenotypic plasticity of circadian entrainment under a range of light conditions

C R C Moreno  1   2 , K Wright Jr  3 , D J Skene  4 , F M Louzada  5
Affiliations

Phenotypic plasticity of circadian entrainment under a range of light conditions

C R C Moreno et al. Neurobiol Sleep Circadian Rhythms. .

Abstract

The response to a zeitgeber, particularly the light/dark cycle, may vary phenotypically. Phenotypic plasticity can be defined as the ability of one genome to express different phenotypes in response to environmental variation. In this opinion paper, we present some evidence that one of the most prominent effects of the introduction of electric light to the everyday life of humans is a significant increase in phenotypic plasticity and differences in interindividual phases of entrainment. We propose that the healthy limits of phenotypic plasticity have been surpassed in contemporary society.

Keywords: Interindividual differences; Light/dark cycle; Natural light; Phenotypic plasticity.

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Conflict of interest statement

K.P.W. reports being a consultant to/and or receiving personal fees from Circadian Therapeutics, Inc., Circadian Biotherapies, Inc., Philips, Inc; and receiving research support from the NIH, the Office of Naval Research, the PAC-12 conference, outside the submitted work. C.R.C.M., D.J.S., and F.M.L. have nothing to disclose.

Figures

Fig. 1
Fig. 1
Correlation between Dim light Melatonin Onset (DLMO) and midsleep time (MSFsc) among rubber tappers from Amazon, Brazil. Rubber tappers with electric lighting at home (n = 31; solid symbols; r = 0.63; p < 0.05); rubber tappers without electric lighting at home (n = 23; open symbols; r = 0.22; ns).
See this image and copyright information in PMC

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