Delayed Sleep Phase Syndrome - Disturbances Of Sleep Timing: Sleep Disorders

Content provided by the Faculty of the Harvard Medical School

Delayed sleep phase syndrome

Almost everyone is programmed for a day that lasts slightly longer than 24 hours, but "night owls" are less sensitive to the environmental cues that help most people maintain a 24-hour cycle. Left to their own devices, they would generally go to sleep and wake up later each successive day. Only by relying on external cues, such as alarm clocks, do they manage to stay in sync. Night owls have trouble getting anything done in the morning.

They may be able to gradually synchronize their schedule with others by going to bed and getting up at the same time every day. However, it's easy for their sleep patterns to go awry when they go on vacation or retire. Night owls often find that a minor shift in sleep/wake cycles such as the onset of daylight savings time, a coast-to-coast trip, or a weekend of late-night parties can throw them off kilter unless they force themselves to get up at the same time.

Resetting your internal clock

If you're already going to bed late and getting up hours later than everyone else, you can reset your biological clock by moving your bedtime progressively later until you've shifted around the clock and are back in sync. To do this, go to bed two hours later each night. Once you have synchronized your schedule to match that of the other people around you, wake yourself up at the same time each day.

You can reset your biological clock.

Often a delayed sleep phase can be reset in a single weekend — something teenagers do routinely. This requires staying up all night on Friday and all day Saturday, then going to bed around 10 p.m. On Sunday, get up at 7 a.m. From then on, adhere closely to the same bedtime and waking time seven days a week.

Exposure to bright light as directed by a sleep specialist — a technique known as light therapy — may be useful in treating delayed sleep phase syndrome. Upon awakening, patients typically sit for 30 minutes facing a specially manufactured box that emits bright light with a minimal amount of ultraviolet light. Melatonin may also have a role; taking 1–6 mg three hours before your current bedtime may help advance your sleep schedule.

Last updated:	January 23, 2007