ABSTRACT
In a brain– computer interface (BCI) the brain provides input directly to the computer through brain signals, without the aid of a mechanically operated device like a keyboard. Because of the ease of collection, high portability of the acquisition systems, low cost, and minimum risk involved, electroencephalography (EEG) has traditionally been the most preferred brain signal for this purpose. One immediate benefit of the BCI technique is better rehabilitation of persons with severe neuromuscular disabilities, such as amyotrophic lateral sclerosis, brainstem stroke, and spinal cord injury. The intent of the user is determined from a wide range of EEG signals, such as event-related potentials, and mu and beta rhythms, recorded from the scalp. Numerous studies have described a vast group of brain signals that might serve as control signals in BCI systems. The control signals employed in BCI systems are visually evoked potentials, slow cortical potentials, P300-evoked potentials, sensory motor rhythms and movement-related potential.
