Daily and Seasonal Variation in the Spectral Composition of Light Exposure in Humans

@article{Thorne2009DailyAS,
  title={Daily and Seasonal Variation in the Spectral Composition of Light Exposure in Humans},
  author={Helen C. Thorne and Kay H. S. Jones and Stuart P Peters and Simon N Archer and Derk-Jan Dijk},
  journal={Chronobiology International},
  year={2009},
  volume={26},
  pages={854 - 866}
}
Light is considered the most potent synchronizer of the human circadian system and exerts many other non-image-forming effects, including those that affect brain function. [] Key Method Twenty-two subjects, aged 22+/-4 yrs (mean+/-SD) participated during the winter months (November-February), and 12 subjects aged 25+/-3 yrs participated during the summer months (April-August). Subjects wore Actiwatch-RGB monitors, as well as Actiwatch-L monitors, for seven consecutive days while living in England.

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