A Brain-Computer Interface (BCI) provides a new communication channel between the brain and the computer. Mental activity leads to changes of electrophysiological signals like the electroencephalogram (EEG) or the electrocorticogram (ECoG). The BCI system detects such changes and transforms them into control signals that can, for example, be used to spell words or to control a cursor on a computer screen. One of the main goals of BCI devices is to enable completely paralyzed patients (locked-in syndrome) to communicate with their environment.




