Proprioceptive feedback in BCI

Motor imagery based brain computer interface (BCI) technology can be used in motor neurorehabilitation. The use of a BCI as a neuroprosthetic for paralyzed limb assistance implies afferent information flow caused by the feedback. It is an open question whether the proprioceptive feedback causes a bias in the modulation of a motor imagery based BCI control signal. We used a BCI coupled with a robotic orthosis fixed to the subjects hand for flexing or extending the subjects fingers. We studied the proprioceptive feedback neurocorrelates and the performance of 2 subjects by compairing their accuracy using a BCI platform in 2 different tasks; motor imagery task without feedback and motor imagery task with fake, proprioceptive feedback. The proprioceptive feedback increased the performance considerably for both subjects. There is a clear desynchronization potentiation of the mu and beta rhythms while the subjects hand was being moved by the orthosis. These findings could be very relevant for the motor neurorehabilitation field.