Read and speak


Of all the sleeping disorders, sleeplessness – insomnia – is the most common. Having trouble falling asleep, staying awake too long, waking up too early and not being able to fall asleep are symptoms of sleeplessness. For most people the complaints don’t last long and are sometimes related to temporary stress. When the complaints occur three or more nights per week and last longer than three months, we can speak of chronic sleeplessness. Sleeplessness can result in problems functioning during the day, such as exhaustion, depression, headaches or muscular tension.

Read and speak

Breathing-related sleeping disorders

In breathing-related sleeping disorders, breathing during the sleep is disrupted. One of the most common disorders is Obstructive Sleep Apnea (OSA). Symptoms of OSA during sleep include snoring, breath-stops, frequently urinating, and problems sleeping on. Often-heard complaints during the day include excessive sleepiness, irritability and decreased concentration.

A less occurring type of apnea is Central Sleep Apnea (CSA). In CSA, breathing in controlled irregularly from the brain, causing short breaks in breathing a partner might notice. Sometimes these breaks are alternated with periods of deep breathing. Snoring is usually less prominent. CSA can involve complaints that include breath stops, superficial sleeping and frequently urinating at night. Furthermore, people might wake up being not rested, and during the day suffer from tiredness or sleepiness.

Read and speak


The main complaint with hypersomnia is excessive sleepiness during the day, even if the sleep-wake cycle seems normal. The amount of sleepiness may vary from mild (for instance nodding off after dinner) to heavy (such as falling asleep in company, or showing automatic behavior during a sleep attack without having a conscious memory of that behavior).

Narcolepsy is an example of a serious and complex hypersomnia. It is characterized by sudden, irresistible sleep attacks. The sleep attacks may be related to tension, but not necessarily so. Narcolepsy patients often also suffer from cataplexy, attacks of sudden muscle relaxation. When they get emotionally excited – laughing, crying or getting mad -, people with cataplexy loose muscle control and fall down. During such attacks, they are unable to speak, but they remain conscious and they continue to breathe.

Read and speak

Circadian rhythm disorders

The biological clock had considerable influence on our day and night rhythm and is an example of a circadian rhythm. A circadian rhythm lasts approximately one day (circa = round, dies = day). If the biological clock is deregulated, a circadian rhythm disorder may occur. You might suffer from sleeplessness when you want to go asleep, or sleepiness when you want to be awake.

Examples of circadian rhythm disorders include the delayed sleep phase syndrome (DSPS) and the advanced sleep phase syndrome (ASPS). People with DSPS fall asleep extremely late; people with ASPS want to go to sleep very early and wake up very early.

Read and speak


Parasomnia is a variety of sleeping disorders where people display deviating behavior or excessive movements during their sleep. Examples are sleepwalking, nighttime anxiety attacks, REM-sleep behavioral disorder and periods of drowsiness. Behavior or movements seem focused, but are executed unconsciously (automatically). As a result, it is impossible to consciously control this behavior.

Read and speak

Sleep-related movement disorders

Sleep-relates movement disorders are usually a type of parasomia. This concerns mostly relatively simple movements during sleep, such as swaying, rhythmic or teeth grinding movements. An example of a sleep-related movement disorder is the restless legs syndrome (RLS). Typical are the (uncontrollable) movements of the legs to alleviate an uncomfortable feeling in the legs.