Sleep disorders - overview
Sleep disorders are problems with sleeping. These include trouble falling or staying asleep, falling asleep at the wrong times, too much sleep, and abnormal behaviors during sleep.
Insomnia; Narcolepsy; Hypersomina; Daytime sleepiness; Sleep rhythm; Sleep disruptive behaviors; Jet lag
There are more than 100 different sleeping and waking disorders. They can be grouped into 4 main categories:
PROBLEMS FALLING AND STAYING ASLEEP
Insomnia includes trouble falling asleep or staying asleep. Episodes may come and go, last up to 3 weeks (be short-term), or be long-lasting (chronic).
PROBLEMS STAYING AWAKE
Hypersomnia is a condition in which people have excessive daytime sleepiness, meaning that they feel tired during the day. Hypersomnia can also include situations in which a person needs to sleep a lot. This may be due to other medical conditions, but can also be due to a problem in the brain. Causes of this problem include:
When no cause for the sleepiness can be found, it is called idiopathic hypersomnia.
PROBLEMS STICKING TO A REGULAR SLEEP SCHEDULE
Problems may also occur when you do not stick to a regular sleep and wake schedule. This occurs when people travel between time zones and with shift workers who are on changing schedules, especially nighttime workers.
Disorders that involve a disrupted sleep schedule include:
Abnormal behaviors during sleep are called parasomnias. They are fairly common in children and include:
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