Narcolepsy comes from two Greek words meaning "benumbing seizure." It is a disorder characterized by uncontrollable brief episodes of sleep (sleep attacks), hypnagogic hallucinations
, cataplexy, and sleep paralysis.
A Hypnagogic hallucinations
are vivid dreamlike sensations that you experience as you are falling asleep.
Narcolepsy is accompanied by the proliferation of histamine neurons, which can cause classic symptoms of narcolepsy, such as cataplexy and hypnagogic hallucinations
. [sup], In addition, an increase of cholinergic receptors is one of the most significant features of narcolepsy, which might comprise an adaptive response to the malfunction of the secretion of acetylcholine and dopamine.
While excessive daytime sleepiness generally persists throughout life, sleep paralysis and hypnagogic hallucinations
For example, REM sleep suppression may help with cataplexy and the hypnagogic hallucinations
. Thus, the clinician and patient may be led astray by the resolution of the psychotic symptoms.
(3,4) These are visual, somatic, auditory or other hallucinations, usually brief though sometimes prolonged, that occur at the transition from wakefulness to sleep (hypnagogic hallucinations
) or from sleep to wakefulness (hypnopompic hallucinations).
. These vivid, often frightening, dream-like experiences occur while dozing or falling asleep.
Barnhill's patient swayed the author though the patient already has a psychotic illness (as well as many other possible contributors such as drug use), but even in sleep disorders hypnopompic or hypnagogic hallucinations
are neither exclusive to narcolepsy, nor particularly pathognomonic.
About 30%-60% of narcoleptic patients have sleep paralysis, a similar proportion have hypnagogic hallucinations
, which occur at sleep onset.
Symptoms of narcolepsy include excessive daytime sleepiness (even dropping off to sleep at any time, whether it be watching TV or driving a car), cataplexy (brief episodes of muscle weakness brought on by strong emotion), sleep paralysis (inability to move occurring at the moment of failing asleep), and hypnagogic hallucinations
(dreamlike images that occur at sleep onset).
Other types of medications help control cataplexy, sleep paralysis and hypnagogic hallucinations
, but for various reasons are not widely used.
Classic narcolepsy patients display the clinical 'tetrad'--cataplexy, hypnagogic hallucinations
, daytime sleep attacks and sleep paralysis.
(22) Complex visual hallucinations in epilepsy are similar to hypnagogic hallucinations
but are rare.