Schalk G, Wolpaw J R, McFarland D J, Pfurtscheller G
Department of Medical Informatics, Institute of Biomedical Engineering, Graz University of Technology, Graz, Austria.
Clin Neurophysiol. 2000 Dec;111(12):2138-44. doi: 10.1016/s1388-2457(00)00457-0.
EEG-based communication could be a valuable new augmentative communication technology for those with severe motor disabilities. Like all communication methods, it faces the problem of errors in transmission. In the Wadsworth EEG-based brain-computer interface (BCI) system, subjects learn to use mu or beta rhythm amplitude to move a cursor to targets on a computer screen. While cursor movement is highly accurate in trained subjects, it is not perfect.
In an effort to develop a method for detecting errors, this study compared the EEG immediately after correct target selection to that after incorrect selection.
The data showed that a mistake is followed by a positive potential centered at the vertex that peaks about 180 ms after the incorrect selection.
The results suggest that this error potential might provide a method for detecting and voiding errors that requires no additional time and could thereby improve the speed and accuracy of EEG-based communication.
