EEG-based "walking" of a tetraplegic in virtual reality

A high spinal cord injured tetraplegic patient was able to generate bursts of beta oscillations in the EEG by imagination of foot movements [1]. Only one single EEG channel was analyzed and classified sample-by-sample by a Brain-Computer Interface (BCI) and used asynchronously to control a virtual environment (VE). The used VE was a virtual street populated with 15 avatars [2]. The patient was placed with his wheelchair in the middle of a 4-wall-projection CAVE and his task was to “walk” towards the end of the virtual street by movement imagination of his paralyzed feet. Every time he was passing by an avatar he had to stop very close to it. The avatar started talking to the patient if he was standing still for one second. After a while, by free will, the subject could imagine the next foot movement and started walking again, till the end of the street was reached.