Brain-Computer Interfacing: How to control computers with thoughts

Brain-Computer Interface (BCI) technology aims at providing communication and control facilities to severely paralyzed people. These patients are not able to manipulate objects or communicate their needs, even though their mental capabilities are intact. Electroencephalographic (EEG) signals recorded from the scalp can be used to decode wishes and intentions. BCI approaches are based on a variety of strategies to generate control signals. For example, the control signals may be the result of visual or auditive stimulation or of imaginary motor tasks. The control signals are analyzed by a translation algorithm which associates a signal to a command. Thus, BCI provides a communication channel not based on nerves and muscles. This paper describes the BCI systems developed at the Center for Sensory-Motor Interaction of Aalborg University, with special emphasis on strategies based on non-motor imagery tasks.