Empirische Inferenz Technical Report 2003

Support Vector Channel Selection in BCI

Designing a Brain Computer Interface (BCI) system one can choose from a variety of features that may be useful for classifying brain activity during a mental task. For the special case of classifying EEG signals we propose the usage of the state of the art feature selection algorithms Recursive Feature Elimination [3] and Zero-Norm Optimization [13] which are based on the training of Support Vector Machines (SVM) [11]. These algorithms can provide more accurate solutions than standard filter methods for feature selection [14]. We adapt the methods for the purpose of selecting EEG channels. For a motor imagery paradigm we show that the number of used channels can be reduced significantly without increasing the classification error. The resulting best channels agree well with the expected underlying cortical activity patterns during the mental tasks. Furthermore we show how time dependent task specific information can be visualized.

Author(s): Lal, TN. and Schröder, M. and Hinterberger, T. and Weston, J. and Bogdan, M. and Birbaumer, N. and Schölkopf, B.
Number (issue): 120
Year: 2003
Month: December
Day: 0
Bibtex Type: Technical Report (techreport)
Digital: 0
Electronic Archiving: grant_archive
Institution: Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
Organization: Max-Planck-Gesellschaft
School: Biologische Kybernetik
Links:

BibTex

@techreport{2482,
  title = {Support Vector Channel Selection in BCI},
  abstract = {Designing a Brain Computer Interface (BCI) system one can choose from a variety of features that
  may be useful for classifying brain activity during a mental task. For the special case of classifying EEG signals we propose the usage of the state of the art feature selection algorithms Recursive Feature Elimination [3] and Zero-Norm Optimization [13] which are based on the training of Support Vector Machines (SVM) [11]. These algorithms can provide more accurate solutions than standard filter methods for feature selection [14].
  
  We adapt the methods for the purpose of selecting EEG channels. For a motor imagery paradigm we
  show that the number of used channels can be reduced significantly without increasing the classification error. The resulting best channels agree well with the expected underlying cortical activity patterns during the mental tasks.
  
  Furthermore we show how time dependent task specific information can be visualized.},
  number = {120},
  organization = {Max-Planck-Gesellschaft},
  institution = {Max Planck Institute for Biological Cybernetics, Tuebingen, Germany},
  school = {Biologische Kybernetik},
  month = dec,
  year = {2003},
  slug = {2482},
  author = {Lal, TN. and Schr{\"o}der, M. and Hinterberger, T. and Weston, J. and Bogdan, M. and Birbaumer, N. and Sch{\"o}lkopf, B.},
  month_numeric = {12}
}