Electrodes Arrangement on Brain-Computer Interface for the ALS's Posture

A brain-computer interface (BCI) can operate a computer by analyzing electroencephalogram data. A BCI does not require body motion; therefore, the physically handicapped, such as those who suffer from amyotrophic lateral sclerosis (ALS), can also operate a computer. However, with ALS patients, attaching electrodes requires significant time and effort. In this study, we examine the number and arrangement of electrodes for a character input BCI in consideration of the limitations encountered with ALS patients. We found that the percentage of correct answers was greater with a smaller number of electrodes than the current number of electrodes. Moreover, we consider that the Cz and CP4 electrode positions are effective for P300 discrimination.