A Second Kind of Light
Mark Rea
In addition to its role in the human visual system, light helps to regulate the timing of many biological functions, including the sleep-wake cycle and the production of key hormones. Scientists are just beginning to understand how light stimulates the
circadian system, and its consequent effect on people’s health and well-being.
Access to the full text of this article is restricted. In order to view this article please log in.