Circadian rhythm sleep disorders affect the timing of sleep. People with circadian rhythm sleep disorders have trouble sleeping and waking at normal times to participate in work, school or social functions. If allowed to sleep according to their internal clocks, they will get enough sleep, but the timing of their sleep will disrupt normal day to day functions. Their are two type of circadian rhythm disorders, Extrinsic and Intrinsic.
Extrinsic Types
- Jet-lag syndrome affects people who travel across multiple time zones.
- Shift work sleep disorder affects people who work nights or rotating shifts.
Intrinsic Types
- Delayed sleep-phase syndrome causes a much later than normal timing of slep onset and awakening.
- Advanced sleep-phase syndrome causes difficulty staying awake in the evening and staying awake in the morning.
- Non-24-hour sleep-wake syndrome causes sleep onset to occur later and later every day, with alertness continuously moving around the clock as well.
- Irregular sleep-wake pattern causes sleeping at very irregular times, often napping throughout the day and waking at night. Total sleep time is usually normal for the person’s age.