title: Volitional electromyographic responses in disorders of consciousness.
abstract: OBJECTIVE
  The aim of the study was to validate the use of electromyography (EMG) for detecting responses to command in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (MCS).
  
  
  METHODS
  Thirty-eight patients were included in the study (23 traumatic, 25 patients >1 year post-onset), 10 diagnosed as being in VS/UWS, eight in MCS- (no response to command) and 20 in MCS+ (response to command). Eighteen age-matched controls participated in the experiment. The paradigm consisted of three commands (i.e. 'Move your hands', 'Move your legs' and 'Clench your teeth') and one control sentence (i.e. 'It is a sunny day') presented in random order. Each auditory stimulus was repeated 4 times within one block with a stimulus-onset asynchrony of 30 seconds.
  
  
  RESULTS
  Post-hoc analyses with Bonferroni correction revealed that EMG activity was higher solely for the target command in one patient in permanent VS/UWS and in three patients in MCS+.
  
  
  CONCLUSIONS
  The use of EMG could help clinicians to detect conscious patients who do not show any volitional response during standard behavioural assessments. However, further investigations should determine the sensitivity of EMG as compared to neuroimaging and electrophysiological assessments.
authors.affiliation: Coma Science Group, Cyclotron Research Center and Neurology Department, University and University Hospital of Liège , Liège , Belgium .
authors.forename: Dina
authors.initials: D
authors.lastname: Habbal
authors.forename: Olivia
authors.initials: O
authors.lastname: Gosseries
authors.forename: Quentin
authors.initials: Q
authors.lastname: Noirhomme
authors.forename: Jerome
authors.initials: J
authors.lastname: Renaux
authors.forename: Damien
authors.initials: D
authors.lastname: Lesenfants
authors.forename: Tristan A
authors.initials: TA
authors.lastname: Bekinschtein
authors.forename: Steve
authors.initials: S
authors.lastname: Majerus
authors.forename: Steven
authors.initials: S
authors.lastname: Laureys
authors.forename: Caroline
authors.initials: C
authors.lastname: Schnakers
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000503:physiopathology*; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018458:Persistent Vegetative State / Q000175:diagnosis / Q000503:physiopathology*; D011379:Prognosis; D020127:Recovery of Function; D016896:Treatment Outcome
keywords: Brain injury; consciousness; electromyogram; minimally conscious state; unresponsive wakefulness syndrome; vegetative state