title: Tactile event-related potentials in amyotrophic lateral sclerosis (ALS): Implications for brain-computer interface.
abstract: OBJECTIVE
  We investigated neurophysiological brain responses elicited by a tactile event-related potential paradigm in a sample of ALS patients. Underlying cognitive processes and neurophysiological signatures for brain-computer interface (BCI) are addressed.
  
  
  METHODS
  We stimulated the palm of the hand in a group of fourteen ALS patients and a control group of ten healthy participants and recorded electroencephalographic signals in eyes-closed condition. Target and non-target brain responses were analyzed and classified offline. Classification errors served as the basis for neurophysiological brain response sub-grouping.
  
  
  RESULTS
  A combined behavioral and quantitative neurophysiological analysis of sub-grouped data showed neither significant between-group differences, nor significant correlations between classification performance and the ALS patients' clinical state. Taking sequential effects of stimuli presentation into account, analyses revealed mean classification errors of 19.4% and 24.3% in healthy participants and ALS patients respectively.
  
  
  CONCLUSIONS
  Neurophysiological correlates of tactile stimuli presentation are not altered by ALS. Tactile event-related potentials can be used to monitor attention level and task performance in ALS and may constitute a viable basis for future BCIs.
  
  
  CONCLUSIONS
  Implications for brain-computer interface implementation of the proposed method for patients in critical conditions, such as the late stage of ALS and the (completely) locked-in state, are discussed.
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy. Electronic address: stefano.silvoni@ospedalesancamillo.net.
authors.forename: S
authors.initials: S
authors.lastname: Silvoni
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, Eberhard-Karls-University, Tübingen, Germany; Dept. for Child- and Adolescent-Psychiatry, Medical University of Vienna, Vienna, Austria.
authors.forename: L
authors.initials: L
authors.lastname: Konicar
authors.affiliation: Dept. of Neuroscience, University of Padova, Italy.
authors.forename: M A
authors.initials: MA
authors.lastname: Prats-Sedano
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, Eberhard-Karls-University, Tübingen, Germany; Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Garcia-Cossio
authors.affiliation: Otto Bock HealthCare GmbH, Duderstadt, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Genna
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Volpato
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Cavinato
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Paggiaro
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, Eberhard-Karls-University, Tübingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Veser
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy.
authors.forename: D
authors.initials: D
authors.lastname: De Massari
authors.affiliation: Dept. of Neurophysiology, I.R.C.C.S. S.Camillo Hospital Foundation, Venice, Italy; Institute of Medical Psychology and Behavioral Neurobiology, Eberhard-Karls-University, Tübingen, Germany; Deutsches Zentrum für Diabetesforschung (DZD), University of Tübingen, Tübingen, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Birbaumer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000503:physiopathology*; D062207:Brain-Computer Interfaces / Q000639:trends; D004558:Electric Stimulation / Q000379:methods; D004569:Electroencephalography / Q000379:methods; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014110:Touch / Q000502:physiology*; D014732:Vibration
keywords: (Partially) locked-in syndrome; Amyotrophic lateral sclerosis (ALS); Brain-computer interface (BCI); Single-trial analysis; Tactile event-related potentials