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 ?
EDS contributed 25% of the model variance, while cataplexy contributed 10%, sleep attack about 2%, sleep onset paralysis about 2% and hypnagogic hallucinations about 1%.
In this case the initial presentation of hypnagogic hallucinations and clinicians' failure to understand the relevance of the patient's reports (and her parents' report) of excessive sleep lead to the repeated incorrect diagnosis of different types of atypical epilepsy and to inappropriate treatment with antiepileptic medications, despite the absence of EEG evidence of epilepsy.
10) Cataplexy is present in about 70% of patients with narcolepsy, whereas sleep paralysis (30% to 50%) and hypnagogic hallucinations (20% to 40%) are experienced less often; all 4 symptoms are present in an estimated 11% to 14% of patients with narcolepsy.
Sometimes this transition to REM sleep can occur immediately upon falling asleep (called SOREMPs) without ever entering NREM sleep, (17) leading to the occurrence of hypnagogic hallucinations and sleep paralysis.
In contrast, a patient afflicted with more severe symptoms, including cataplexy, hypnagogic hallucinations and sleep fragmentation may require a more aggressive pharmaceutical paradigm.
Symptoms of cataplexy and/or hypnagogic hallucinations require additional agents such as sodium oxybate, SSRI's or tricyclic antidepressants.
Additionally, a person with narcolepsy may have cataplexy, sleep paralysis, and/or hypnagogic hallucinations.