A Note on Brain Actuated Spelling with the Berlin Brain-Computer Interface

  • Benjamin Blankertz
  • Matthias Krauledat
  • Guido Dornhege
  • John Williamson
  • Roderick Murray-Smith
  • Klaus-Robert Müller
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4555)


Brain-Computer Interfaces (BCIs) are systems capable of decoding neural activity in real time, thereby allowing a computer application to be directly controlled by the brain. Since the characteristics of such direct brain-to-computer interaction are limited in several aspects, one major challenge in BCI research is intelligent front-end design. Here we present the mental text entry application ‘Hex-o-Spell’ which incorporates principles of Human-Computer Interaction research into BCI feedback design. The system utilises the high visual display bandwidth to help compensate for the extremely limited control bandwidth which operates with only two mental states, where the timing of the state changes encodes most of the information. The display is visually appealing, and control is robust. The effectiveness and robustness of the interface was demonstrated at the CeBIT 2006 (world’s largest IT fair) where two subjects operated the mental text entry system at a speed of up to 7.6 char/min.


Motor Imagery Text Entry Rehabilitation Engineer Text Entry Method P300 Speller 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Benjamin Blankertz
    • 1
    • 2
  • Matthias Krauledat
    • 1
    • 2
  • Guido Dornhege
    • 2
  • John Williamson
    • 3
  • Roderick Murray-Smith
    • 3
    • 4
  • Klaus-Robert Müller
    • 1
    • 2
  1. 1.Technical University Berlin, BerlinGermany
  2. 2.Fraunhofer FIRST (IDA), BerlinGermany
  3. 3.University of Glasgow, GlasgowScotland
  4. 4.Hamilton Institute, NUI MaynoothIreland

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