01633nas a2200157   4500008004100000022001400041245009200055210006900147260000900216300001400225490000600239520114100245100002001386700002101406856004801427       2009                        eng d  a1941-118900aClinical Applications of Brain-Computer Interfaces: Current State and Future Prospects.0 aClinical Applications of BrainComputer Interfaces Current State   c2009  a187–1990 v23 aBrain-computer interfaces (BCIs) allow their users to communicate or control external devices using brain signals rather than the brain's normal output pathways of peripheral nerves and muscles. Motivated by the hope of restoring independence to severely disabled individuals and by interest in further extending human control of external systems, researchers from many fields are engaged in this challenging new work. BCI research and development have grown explosively over the past two decades. Efforts have recently begun to provide laboratory-validated BCI systems to severely disabled individuals for real-world applications. In this review, we discuss the current status and future prospects of BCI technology and its clinical applications. We will define BCI, review the BCI-relevant signals from the human brain, and describe the functional components of BCIs. We will also review current clinical applications of BCI technology, and identify potential users and potential applications. Finally, we will discuss current limitations of BCI technology, impediments to its widespread clinical use, and expectations for the future.1 aMak, Joseph, N.1 aWolpaw, Jonathan  uhttp://www.ncbi.nlm.nih.gov/pubmed/20442804