light later in the night (12:00 am or later). It is important to remember to avoid receiving light too close to one’s ‘peak time’, since only an accurate body temperature minimum can be established by a sleep lab. Following this schedule will reset the body clock in as little as a few days. Once the desired shift is achieved, light should be received at the regular wake-up time.

Understanding how the body reacts to light signals allows one to better control the sleep/wake cycle.

CONCLUSION
This information should prove helpful in understanding sleep problems associated with circadian rhythm disorders. Understanding how the body reacts to light signals allows one to better control the sleep/wake cycle, and also effectively adjust for shift work or jet lag.