References on Light and the Biological Clock

Practice Parameters for the Use of Light Therapy in the Treatment of Sleep Disorders. Sleep 1999; 22(5):641-60.
Standards of Practice Committee, American Academy of Sleep Medicine. AL Chesson Jr, M Littner, D Davila, WM Anderson, M Grigg-Damberger, K Hartse, S Johnson, M Wise

"Light therapy can be useful in treatment of DSPS (Delayed Sleep Phase Syndrome)and ASPS (Advanced Sleep Phase Syndrome)." Abstract

Light Treatment for Sleep Disorders: Consensus Report II. Basic Properties of Circadian Physiology and Sleep Regulation. Journal of Biological Rhythms 1995; 10(2);113-25
DJ Dijk, Z Boulos, CI Eastman, AJ Lewy, SS Campbell, M Terman.

"In humans and other mammals the daily light-dark (LD) cycle is a major synchronizer responsible for entrainment of circadian rhythms to the 24-h day, and phase response curves (PRCs) to light have been obtained. In humans, phase delays can be induced by light exposure scheduled before the minimum of the endogenous circadian rhythm of core body temperature (CBT), whereas phase advances are induced when light exposure is scheduled after the minimum of CBT." Abstract