title: Decoding of motor intentions from epidural ECoG recordings in severely paralyzed chronic stroke patients.
abstract: OBJECTIVE
  Recently, there have been several approaches to utilize a brain-computer interface (BCI) for rehabilitation with stroke patients or as an assistive device for the paralyzed. In this study we investigated whether up to seven different hand movement intentions can be decoded from epidural electrocorticography (ECoG) in chronic stroke patients.
  
  
  METHODS
  In a screening session we recorded epidural ECoG data over the ipsilesional motor cortex from four chronic stroke patients who had no residual hand movement. Data was analyzed offline using a support vector machine (SVM) to decode different movement intentions.
  
  
  RESULTS
  We showed that up to seven hand movement intentions can be decoded with an average accuracy of 61% (chance level 15.6%). When reducing the number of classes, average accuracies up to 88% can be achieved for decoding three different movement intentions.
  
  
  CONCLUSIONS
  The findings suggest that ipsilesional epidural ECoG can be used as a viable control signal for BCI-driven neuroprosthesis. Although patients showed no sign of residual hand movement, brain activity at the ipsilesional motor cortex still shows enough intention-related activity to decode different movement intentions with sufficient accuracy.
authors.affiliation: Wilhelm-Schickard-Institute for Computer Science-University of Tübingen, Sand 13, D-72076 Tübingen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Spüler
authors.forename: A
authors.initials: A
authors.lastname: Walter
authors.forename: A
authors.initials: A
authors.lastname: Ramos-Murguialday
authors.forename: G
authors.initials: G
authors.lastname: Naros
authors.forename: N
authors.initials: N
authors.lastname: Birbaumer
authors.forename: A
authors.initials: A
authors.lastname: Gharabaghi
authors.forename: W
authors.initials: W
authors.lastname: Rosenstiel
authors.forename: M
authors.initials: M
authors.lastname: Bogdan
mesh_terms: D000368:Aged; D002908:Chronic Disease; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D033182:Intention; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D010243:Paralysis / Q000175:diagnosis / Q000503:physiopathology*; D012720:Severity of Illness Index; D020521:Stroke / Q000175:diagnosis / Q000503:physiopathology*