Simultaneous brain-computer interfacing and motor control: Expanding the reach of non-invasive BCIs

Brain-computer interfaces (BCIs) have traditionally been developed for paralyzed and locked-in individuals with no motor control. However, there is a much larger population of patients with some residual motor function as well as the general population of able-bodied individuals, both of whom could benefit significantly from BCIs. An important question that has yet to be systematically studied is: can subjects use BCIs simultaneously with overt motor activity? We present results from a preliminary study aimed at exploring this question. Three subjects used hand motor imagery in an electroencephalographic (EEG) BCI while simultaneously using a joystick to control a cursor. Particular attention was paid to preventing potential muscle artifacts from influencing imagery-based control. All three subjects were able to use the hybrid "imagery+joystick" mode of control over two days, demonstrating the ability to learn and significantly improve performance. These results suggest that subjects can potentially augment their normal human sensorimotor capability by exercising direct brain control over devices concurrently with overt motor control.