What is Narcolepsy?
Narcolepsy is a neurological condition characterized by Excessive Daytime Sleepiness (EDS). A narcoleptic will most likely experience disturbed nocturnal sleep, which is often confused with insomnia, and disorder of REM or rapid eye movement sleep. A narcoleptic may also sleep at any random time.
The main characteristic of narcolepsy is overwhelming excessive daytime sleepiness (EDS), even after an adequate amount of night time sleep. A person with narcolepsy is likely to become drowsy or to fall asleep, often at inappropriate times and places. Daytime naps may occur without warning and may be physically irresistible. These naps can occur several times a day. They are typically refreshing, but only for a few hours. Drowsiness may persist for prolonged periods of time. In addition, night-time sleep may be fragmented with frequent awakenings.
Four other classic symptoms of narcolepsy, which may not occur in all patients, are cataplexy, sleep paralysis, hypnagogic hallucinations, and automatic behavior. Cataplexy is an episodic condition featuring loss of muscle function, ranging from slight weakness (such as limpness at the neck or knees, sagging facial muscles, or inability to speak clearly) to complete body collapse. Episodes may be triggered by sudden emotional reactions such as laughter, anger, surprise, or fear, and may last from a few seconds to several minutes. The person remains conscious throughout the episode.
Sleep paralysis is the temporary inability to talk or move upon awakening. It may last a few seconds to minutes. This is often frightening but is not dangerous.
Hypnagogic hallucinations are vivid, often frightening, dreamlike experiences that occur while dozing, falling asleep and/or while awakening.
Automatic behavior means that a person continues to function (talking, putting things away, etc.) during sleep episodes, but awakens with no memory of performing such activities. It is estimated that up to 40 percent of people with narcolepsy experience automatic behavior during sleep episodes.
Daytime sleepiness, sleep paralysis, and hypnagogic hallucinations also occur in people who do not have narcolepsy, more frequently in people who are suffering from extreme lack of sleep. Cataplexy is generally considered to be unique to narcolepsy and is analogous to sleep paralysis in that the usually protective paralysis mechanism occurring during sleep is inappropriately activated. The opposite of this situation (failure to activate this protective paralysis) occurs in rapid eye movement behavior disorder
In most cases, the first symptom of narcolepsy to appear is excessive and overwhelming daytime sleepiness. The other symptoms may begin alone or in combination months or years after the onset of the daytime naps. There are wide variations in the development, severity, and order of appearance of cataplexy, sleep paralysis, and hypnagogic hallucinations in individuals. Only about 20 to 25 percent of people with narcolepsy experience all four symptoms. The excessive daytime sleepiness generally persists throughout life, but sleep paralysis and hypnagogic hallucinations may not.
Although these are the common symptoms of narcolepsy, many (although less than 40% of people with narcolepsy) also suffer from insomnia for extended periods of time. This is most often from
* An excess of sleep.
* Use of self-medications such as energy drinks, or caffeinated drinks.
The symptoms of narcolepsy, especially the excessive daytime sleepiness and cataplexy, often become severe enough to cause serious problems in a person's social, personal, and professional life.
Normally, when an individual is awake, brain waves show a regular rhythm. When a person first falls asleep, the brain waves become slower and less regular. This sleep state is called non-rapid eye movement (NREM) sleep. After about an hour and a half of NREM sleep, the brain waves begin to show a more active pattern again. This sleep state, called REM sleep (rapid eye movement sleep), is when most remembered dreaming occurs. Associated with the EEG observed waves during REM sleep muscle atonia is present (called REM atonia).
In narcolepsy, the order and length of NREM and REM sleep periods are disturbed, with REM sleep occurring at sleep onset instead of after a period of NREM sleep. Thus, narcolepsy is a disorder in which REM sleep appears at an abnormal time. Also, some of the aspects of REM sleep that normally occur only during sleep — lack of muscular control, sleep paralysis, and vivid dreams — occur at other times in people with narcolepsy. For example, the lack of muscular control can occur during wakefulness in a cataplexy episode; it is said that there is intrusion of REM atonia during wakefulness. Sleep paralysis and vivid dreams can occur while falling asleep or waking up. Simply put, the brain does not pass through the normal stages of dozing and deep sleep but goes directly into (and out of) rapid eye movement (REM) sleep. This has several consequences:
* Nighttime sleep does not include much deep sleep, so the brain tries to "catch up" during the day, hence EDS
* May visibly fall asleep at any moment (such motions as head bobbing are common)
* People with narcolepsy fall quickly into what appears to be very deep sleep
* They wake up suddenly and can be disoriented when they do (dizziness is a common occurrence)
* They have very vivid dreams, which they often remember
* People with narcolepsy may dream even when they only fall asleep for a few seconds.