title: A motor signature of REM sleep behavior disorder.
abstract: BACKGROUND
  The purpose of this study was to determine if there was a common pattern in movements during REM sleep behavior disorder (RBD).
  
  
  METHODS
  We blindly compared video-monitored movements during RBD (n = 136 clips) and wakefulness/arousal (n = 53 clips) in patients with Parkinson's disease (n = 29) and without parkinsonism (idiopathic RBD, n = 31; narcolepsy, n = 5).
  
  
  RESULTS
  The scorers accurately guessed the sleep/wake stage of 94% of video clips. Compared with wake movements, RBD movements were faster and more often repeated, jerky, and pseudohallucinatory, not self-centered, never associated with tremor, and rarely involved the environment in an appropriate manner. A specific posture of the hand (limp wrist with flexed digits) during grasping movements was evidenced during RBD in 48% of patients, reminiscent of hand-babbling in babies.
  
  
  CONCLUSIONS
  These characteristics of movements were found in the 3 conditions (Parkinson's disease, idiopathic RBD, and primary narcolepsy), delineating a common motor signature of RBD.
authors.affiliation: Sleep Disorders Unit, Pitié-Salpêtrière Hospital, APHP, Paris, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Oudiette
authors.forename: Smaranda
authors.initials: S
authors.lastname: Leu-Semenescu
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Roze
authors.forename: Marie
authors.initials: M
authors.lastname: Vidailhet
authors.forename: Valérie Cochen
authors.initials: VC
authors.lastname: De Cock
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Golmard
authors.forename: Isabelle
authors.initials: I
authors.lastname: Arnulf
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000175:diagnosis / Q000209:etiology*; D009290:Narcolepsy / Q000150:complications; D017286:Polysomnography; D020187:REM Sleep Behavior Disorder / Q000150:complications* / Q000175:diagnosis*; D014741:Video Recording; D014851:Wakefulness / Q000502:physiology