Intrinsic sleep disorders

These are disorders that originate or develop within the body.

1. Psychophysiological insomnia

People with psychophysiological insomnia react to situations that are psychologically stressful with bodily tension or other physical complaints, and they learn to associate certain things with emotions that prevent sleep. People with this disorder typically have a focused absorption on their sleep problems, which itself interferes with sleep.

2. Sleep state misperception

This disorder involves an honest complaint of insomnia or excessive sleepiness when there is no objective evidence that sleep is disturbed or lacking. Often seen in people in middle or late adulthood. They feel they are not able to sleep as long or as well as they could in former years.

3. Idiopathic insomnia

Idiopathic insomnia is a lifelong inability to get adequate sleep that has no observable cause. It is assumed that this difficulty is due to an abnormality of sleep-wake control systems in the brain. It may also be due to a problem in the sleep-inducing and -maintaining systems, or hyperactivity in the arousal systems.

4. Narcolepsy

Narcolepsy is a disorder characterized by excessive sleepiness, abnormal REM sleep, cataplexy, hypnagogic hallucinations, and problems sleeping at night.

5. Recurrent hypersomnia

People with this disorder have recurrent episodes of extreme sleepiness and huge sleep needs. Episodes of hypersomnia usually last several days to several weeks, and occur twice a year, on average (although they can occur as many as 12 times a year). Victims sleep as much as 18 to 20 hours a day during these episodes, waking only to eat and go to the bathroom.

6. Idiopathic hypersomnia

Idiopathic hypersomnia is a disorder in which the patient complains of excessive sleepiness and prolonged sleep at night. What distinguishes this disorder from normal long sleepers and narcoleptics is that in case of idiopathic hypersomnia, there are numerous episodes of non-REM sleep that last for up to two hours. For this reason, this disorder is sometimes called non-REM narcolepsy. Since extreme sleepiness and large sleep need can be a symptom of many other sleep disorders, like narcolepsy and sleep apnea, it's important that those be ruled out before making this diagnosis.

7. Posttraumatic hypersomnia

Excessive sleepiness that develops as the result of physical injury or disease in the central nervous system. It can be caused by brain injury, neurosurgery, infection, or spinal cord injury. The hypersomnia usually goes away over weeks or months.

8. Obstructive sleep apnea syndrome

In obstructive sleep apnea, breathing is blocked during sleep when the airway pulls shut. This causes sleep disruption, dropping oxygen levels in the blood, and cardiovascular problems.

9. Central sleep apnea syndrome

This is a rare type of apnea that occurs not when the throat is blocked but when the patient can't make the effort necessary to pull air into the lungs. It is usually the result of problems in the neurological control of breathing, or with the muscles associated with breathing.

10. Central alveolar hypoventilation syndrome

During sleep, everyone naturally takes less air into the lungs than when awake. If there are problems with gas exchange in the lungs (for instance, caused by emphysema), there may be problems getting enough oxygen during the night, and sleep is disturbed. Because we naturally take in a larger volume of oxygen during the day, there may not be similar problems during the day.

11. Periodic limb-movement disorder

PLM disorder occurs when the sleeper periodically moves a limb (usually a leg) in exactly the same way over the course of the night. A typical movement would be a kick or flex of the leg every 10 seconds. These movements disrupt sleep and lead to insomnia and daytime sleepiness.