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A model of phototransduction by the human circadian system
Mark S Rea1, Mariana G Figueiro, John D Bullough
1Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA. ream@roi.edu
Abstract:
The absolute and spectral sensitivities to light by the human circadian system, measured through melatonin suppression or phase shifting response, are beginning to emerge after a quarter century of active research. The present paper outlines a hypothesized model of human circadian phototransduction that is consistent with the known neuroanatomy and physiology of the human visual and circadian systems. Spectral opponency is fundamental to the model, providing a parsimonious explanation of some recently published data. The proposed model offers a framework for hypothesis testing and subsequent discussion of the practical aspects of architectural lighting with respect to light and health.
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