Effects of an advanced sleep schedule and morning short wavelength light exposure on circadian phase in young adults with late sleep schedules.

ABSTRACT:

Objective

We examined the effects of an advanced sleep/wake schedule and morning short wavelength (blue) light in 25 adults (mean age±SD=21.8±3 years; 13 women) with late sleep schedules and subclinical features of delayed sleep phase disorder (DSPD).

Methods

After a baseline week, participants kept individualized, fixed, advanced 7.5-h sleep schedules for 6days. Participants were randomly assigned to groups to receive "blue" (470nm, ∼225lux, n=12) or "dim" (<1lux, n=13) light for 1h after waking each day. Head-worn "Daysimeters" measured light exposure; actigraphs and sleep diaries confirmed schedule compliance. Salivary dim light melatonin onset (DLMO), self-reported sleep, and mood were examined with 2×2 ANOVA.

Results

After 6days, both groups showed significant ci

SUBMITTER: Sharkey KM 

PROVIDER: S-EPMC3145013 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature