Electrodes Used in Brain Computer Interface

Brain Computer Interface (BCI) has been developed since last 30 years and now it has profounded in diverse areas. In 1964, the description of BCI was first given by Dr. Grey Walter. BCI, is a method of communication between the brain and any external device which helps brain signals to guide some external activities. BCI provides a means of communication to disabled people who are totally paralysed or locked in by neurological neuromuscular disorder such as spinal cord injury, brain stem stroke and amyotrophic lateral scierosis. First, the review deals with the classification of electrodes in which we have discussed contact and non contact electrodes. Second, the review deals with various types of dry electrodes, its fabrication and characteristics which is a type of contact electrodes. It comprises multipoint spiked dry electrodes, carbon nano tube. Third, the review deals with water and gel electrodes and its setup for measuring EEG recording, which is also a type of contact electrode. Fourth, the review deals with capacitive electrodes, which is non contact type electrode, its design and advantages. Fifth, the review deals with various setup of EEG with three different types of electrodes regarding signals that is P300, Motar imagery and SSVEP. Sixth, the review deals with comparison between various electrodes such as active and passive, dry, gel and water, contact and non contact electrodes.