Brain–Computer Interfaces

Brain–computer interfaces (BCIs) have emerged as a novel technology that bridges the brain with external devices. BCIs have been developed to decode human’s intention, leading to direct brain control of a computer or device without going through the neuromuscular pathway. Bidirectional brain–computer interfaces not only allow brain control but also open the door for modulating the central nervous system through neural interfacing. We review the concepts, principles, and various building blocks of BCIs, from signal acquisition, signal processing, feature extraction, feature translation, to device control, and various applications. The performance assessment and challenges of BCIs are also discussed. Examples of noninvasive BCIs are discussed to aid readers for an in-depth understanding of the noninvasive BCI technology, although this chapter is aimed at providing a general introduction to brain–computer interfaces.