rapid eye movement sleep without atonia
Also written as: RWA — Rapid Eye Movement Sleep Without Atonia
A polysomnographic finding where normal muscle paralysis during REM sleep is absent, often associated with REM sleep behavior disorder.
Full Definition
Rapid eye movement sleep without atonia (RWA) refers to the persistence of muscle tone during REM sleep when muscles should normally be paralyzed. This polysomnographic finding is characterized by excessive chin or limb muscle activity during REM sleep phases. RWA is strongly associated with REM sleep behavior disorder and may be an early marker of synucleinopathies such as Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy. In geriatric psychiatry, identifying RWA can aid in early detection of neurodegenerative diseases and guide both treatment decisions and family counseling about potential future cognitive decline.
Usage
Usage note: Technical term requiring understanding of sleep physiology; distinct from REM sleep behavior disorder itself.
In Context
- "Polysomnography revealed rapid eye movement sleep without atonia, suggesting possible future neurodegenerative disease." — Sleep study interpretation
- "The presence of rapid eye movement sleep without atonia warranted neurological follow-up for parkinsonism screening." — Referral documentation