We normally think of the eye as an organ for vision, but due to the discovery of additional nerve connections from recently-detected novel photoreceptor cells in the eye to the brain, it is now understood how light also mediates and controls a large number of biochemical processes in the human body. The most important findings are related to the control of the biological clock and to the regulation of some important hormones through regular light-dark rhythms. This in turn means that lighting has a large influence on health, well-being and alertness. Light sends signals via the novel photoreceptor cells and a separate nerve system to our biological clock,.
