Medical and Biological Engineering and Computing

, Volume 34, Issue 5, pp 382–388

Graz brain-computer interface II: towards communication between humans and computers based on online classification of three different EEG patterns

  • J. Kalcher
  • D. Flotzinger
  • Ch. Neuper
  • S. Gölly
  • G. Pfurtscheller
Communication

Abstract

The paper describes work on the brain-computer interface (BCI). The BCI is designed to help patients with severe motor impairment (e.g. amyotropic lateral sclerosis) to communicate with their environment through wilful modification of their EEG. To establish such a communication channel, two major prerequisites have to be fulfilled: features that reliably describe several distinctive brain states have to be available, and these features must be classified on-line, i.e. on a single-trial basis. The prototype Graz BCI II, which is based on the distinction of three different types of EEG pattern, is described, and results of online and offline classification performance of four subjects are reported. The online results suggest that, in the best case, a classification accuracy of about 60% is reached after only three training sessions. The offline results show how selection of specific frequency bands influences the classification performance in singletrial data.

Keywords

Brain-computer interface electro-encephalogram EEG classification Eventrelated desynchronisation (ERD) Learning vector quantisation 

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Copyright information

© IFMBE 1996

Authors and Affiliations

  • J. Kalcher
    • 1
  • D. Flotzinger
    • 1
  • Ch. Neuper
    • 2
  • S. Gölly
    • 2
  • G. Pfurtscheller
    • 1
    • 2
  1. 1.Department of Medical InformaticsInstitute of Biomedical EngineeringGrazAustria
  2. 2.Ludwig Boltzman-Institute of Medical Informatics and NeuroinformaticsGraz University of TechnologyGrazAustria

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