Demonstration of rapid light-induced advances and delays of the human circadian clock using hormonal phase markers.

@article{vanCauter1994DemonstrationOR,
  title={Demonstration of rapid light-induced advances and delays of the human circadian clock using hormonal phase markers.},
  author={Eve van Cauter and Jeppe Sturis and Maria M Byrne and John D Blackman and Rachel Leproult and G Ofek and Mireille L’Hermite-Bal{\'e}riaux and Samuel Refetoff and Fred W. Turek and Olivier van Reeth},
  journal={The American journal of physiology},
  year={1994},
  volume={266 6 Pt 1},
  pages={
          E953-63
        }
}
To determine the magnitude and direction of phase shifts of human circadian rhythms occurring within 1 day after a single exposure to bright light, plasma thyrotropin, melatonin, and cortisol levels and body temperature were monitored for 38 h in 17 men who were each studied two times, once during continuous dim light conditions and once with light exposure. After a period of entrainment to a fixed sleep-wake cycle, a 3-h light pulse (5,000 lux) was presented under constant routine conditions… 

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