hypnagogic hallucination


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Related to hypnagogic hallucination: narcolepsy, hypnopompic hallucination

hallucination

 [hah-loo″sĭ-na´shun]
a sensory impression (sight, touch, sound, smell, or taste) that has no basis in external stimulation. Hallucinations can have psychologic causes, as in mental illness, or they can result from drugs, alcohol, organic illnesses, such as brain tumor or senility, or exhaustion. When hallucinations have a psychologic origin, they usually represent a disguised form of a repressed conflict. adj. adj hallu´cinative, hallu´cinatory.
auditory hallucination a hallucination of hearing; the most common type.
gustatory hallucination a hallucination of taste.
haptic hallucination tactile hallucination.
hypnagogic hallucination a vivid, dreamlike hallucination occurring at sleep onset.
hypnopompic hallucination a vivid, dreamlike hallucination occurring on awakening.
kinesthetic hallucination a hallucination involving the sense of bodily movement.
olfactory hallucination a hallucination of smell.
somatic hallucination a hallucination involving the perception of a physical experience occurring within the body.
tactile hallucination a hallucination of touch.
visual hallucination a hallucination of sight.

hyp·na·gog·ic hal·lu·ci·na·tion

hallucination occurring when going to sleep in the period between wakefulness and sleep; one of the components of narcolepsy.
Synonym(s): hypnagogic image

hypnagogic hallucination

[hip′nəgoj′ik]
Etymology: Gk, hypnos, sleep, agogos, leading
a vivid image that occurs while falling asleep.

hyp·na·gog·ic hal·lu·ci·na·tion

(hip'nă-goj'ik hă-lū'si-nā'shŭn)
A common symptom in narcolepsy characterized by vivid, dreamlike perceptions occurring with sleep onset. Often these perceptions involve fearful situations that are described as realistic and include visual, tactile, and auditory hallucinations.
References in periodicals archive ?
GHB treatment has a high rate of success in reducing cataplexy, sleep attacks, sleep paralysis, and hypnagogic hallucinations.
Other types of medications help control cataplexy, sleep paralysis and hypnagogic hallucinations, but for various reasons are not widely used.
For example, REM sleep suppression may help with cataplexy and the hypnagogic hallucinations.
It is believed that the unmet need for REM sleep during the night causes abnormal REM sleep to intrude into wakefulness, causing the REMrelated symptoms of cataplexy, sleep paralysis, and hypnagogic hallucinations.
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).
Narcolepsy is a complex, lifelong neurological disease characterized by fragmented nighttime sleep, excessive daytime somnolence (EDS), cataplexy, sleep paralysis, and hypnagogic hallucinations.
Classic narcolepsy patients display the clinical 'tetrad'--cataplexy, hypnagogic hallucinations, daytime sleep attacks and sleep paralysis.
Even sleep specialists may not fully recognize the symptoms of narcolepsy, with only a fifth (22%) identifying all five symptoms of the disease - excessive daytime sleepiness, cataplexy (sudden loss of muscle tone), sleep paralysis, hypnagogic hallucinations and disruptive nocturnal sleep.