Photic Resetting of the Human Circadian Pacemaker in the Absence of Conscious Vision

  title={Photic Resetting of the Human Circadian Pacemaker in the Absence of Conscious Vision},
  author={Elizabeth B. Klerman and Theresa L. Shanahan and Daniel J. Brotman and David W. Rimmer and Jonathan S. Emens and Joseph F. Rizzo and Charles A. Czeisler},
  journal={Journal of Biological Rhythms},
  pages={548 - 555}
Ocular light exposure patterns are the primary stimuli for entraining the human circadian system to the local 24-h day. Many totally blind persons cannot use these stimuli and, therefore, have circadian rhythms that are not entrained. However, a few otherwise totally blind persons retain the ability to suppress plasma melatonin concentrations after ocular light exposure, probably using a neural pathway that includes the site of the human circadian pacemaker, suggesting that light information is… 

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