Understanding human biological rhythm. Therapeutic principles of bright light and melatonin for sleep disorders of circadian rhythm

In this review, the authors explain how human circadian rhythm has developed in the process of evolution, mechanisms of human circadian control, modification of human circadian rhythm and therapeutic principles of circadian rhythm related sleep disorders. In order to treat circadian rhythm related sleep disorders, precise understanding of the mechanism and proper use of circadian phase modifiers are necessary. Therapeutic principles involve bright light, melatonin, exercise and their phase response curves.