EEG-Based Asynchronous BCI Controls Functional Electrical Stimulation in a Tetraplegic Patient
1 Laboratory of Brain-Computer Interfaces, Institute of Computer Graphics and Vision, and Ludwig Boltzmann-Institute for Medical Informatics and Neuroinformatics, Graz University of Technology, Inffeldgasse 16a, Graz 8010, Austria
2 Laboratory of Brain-Computer Interfaces, Institute of Computer Graphics and Vision, Graz University of Technology, Inffeldgasse 16a, Graz 8010, Austria
3 Department of Traumatology, Hospital Villach, Nikolaigasse 43, Villach 9400, Austria
4 Department II, Orthopedic Hospital of Heidelberg University, Schlierbacher Landstraße 200a, Heidelberg 69118, Germany
EURASIP Journal on Advances in Signal Processing 2005, 2005:628453 doi:10.1155/ASP.2005.3152Published: 17 November 2005
The present study reports on the use of an EEG-based asynchronous (uncued, user-driven) brain-computer interface (BCI) for the control of functional electrical stimulation (FES). By the application of FES, noninvasive restoration of hand grasp function in a tetraplegic patient was achieved. The patient was able to induce bursts of beta oscillations by imagination of foot movement. These beta oscillations were recorded in a one EEG-channel configuration, bandpass filtered and squared. When this beta activity exceeded a predefined threshold, a trigger for the FES was generated. Whenever the trigger was detected, a subsequent switching of a grasp sequence composed of 4 phases occurred. The patient was able to grasp a glass with the paralyzed hand completely on his own without additional help or other technical aids.