Efficacy of enhanced evening light for advanced sleep phase syndrome.

This study tested whether a newly designed enhanced evening light therapy was well tolerated and effective in relieving symptoms of Advanced, Sleep Phase Syndrome (ASPS). Participants with self-reported ASPS symptoms were 47 older adults (21 men and 26 women, age 60-86). After baseline, participants underwent 28 consecutive days of either dim or enhanced intensity light treatment for 2-3 hr in the evening.