title: Probing command following in patients with disorders of consciousness using a brain-computer interface.
abstract: OBJECTIVE
  To determine if brain-computer interfaces (BCIs) could serve as supportive tools for detecting consciousness in patients with disorders of consciousness by detecting response to command and communication.
  
  
  METHODS
  We tested a 4-choice auditory oddball EEG-BCI paradigm on 16 healthy subjects and 18 patients in a vegetative state/unresponsive wakefulness syndrome, in a minimally conscious state (MCS), and in locked-in syndrome (LIS). Subjects were exposed to 4 training trials and 10 -12 questions.
  
  
  RESULTS
  Thirteen healthy subjects and one LIS patient were able to communicate using the BCI. Four of those did not present with a P3. One MCS patient showed command following with the BCI while no behavioral response could be detected at bedside. All other patients did not show any response to command and could not communicate with the BCI.
  
  
  CONCLUSIONS
  The present study provides evidence that EEG based BCI can detect command following in patients with altered states of consciousness and functional communication in patients with locked-in syndrome. However, BCI approaches have to be simplified to increase sensitivity.
  
  
  CONCLUSIONS
  For some patients without any clinical sign of consciousness, a BCI might bear the potential to employ a "yes-no" spelling device offering the hope of functional interactive communication.
authors.affiliation: Coma Science Group, Cyclotron Research Centre, University and University Hospital of Liège, Liège, Belgium.
authors.forename: Dorothée
authors.initials: D
authors.lastname: Lulé
authors.forename: Quentin
authors.initials: Q
authors.lastname: Noirhomme
authors.forename: Sonja C
authors.initials: SC
authors.lastname: Kleih
authors.forename: Camille
authors.initials: C
authors.lastname: Chatelle
authors.forename: Sebastian
authors.initials: S
authors.lastname: Halder
authors.forename: Athena
authors.initials: A
authors.lastname: Demertzi
authors.forename: Marie-Aurélie
authors.initials: MA
authors.lastname: Bruno
authors.forename: Olivia
authors.initials: O
authors.lastname: Gosseries
authors.forename: Audrey
authors.initials: A
authors.lastname: Vanhaudenhuyse
authors.forename: Caroline
authors.initials: C
authors.lastname: Schnakers
authors.forename: Marie
authors.initials: M
authors.lastname: Thonnard
authors.forename: Andrea
authors.initials: A
authors.lastname: Soddu
authors.forename: Andrea
authors.initials: A
authors.lastname: Kübler
authors.forename: Steven
authors.initials: S
authors.lastname: Laureys
mesh_terms: D000328:Adult; D000368:Aged; D001143:Arousal; D062207:Brain-Computer Interfaces; D003244:Consciousness Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology*; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D018913:Event-Related Potentials, P300; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018458:Persistent Vegetative State / Q000503:physiopathology / Q000523:psychology; D011782:Quadriplegia / Q000503:physiopathology / Q000523:psychology