cataplexy
Pronunciation: KAT-ah-plek-see
Sudden, temporary loss of muscle tone triggered by strong emotions, typically associated with narcolepsy.
Full Definition
Cataplexy is a neurological phenomenon characterized by the sudden and temporary loss of voluntary muscle control, usually triggered by intense emotional states such as laughter, surprise, or anger. Episodes can range from slight weakness in facial muscles to complete collapse, though consciousness remains intact throughout. Cataplexy is most commonly associated with narcolepsy with cataplexy (type 1 narcolepsy) and is caused by the deficiency of hypocretin/orexin neurotransmitters in the brain. The condition is considered pathognomonic for narcolepsy when classic presentations occur.
Usage
Usage note: Often misspelled as 'catalepsy' - cataplexy involves muscle weakness, while catalepsy involves muscle rigidity.
In Context
- "The patient's cataplexy episodes were triggered by sudden laughter, causing her knees to buckle." — Clinical examination notes
- "Partial cataplexy affecting only facial muscles was observed during the patient interview." — Sleep clinic assessment