Human Error in P300 Speller Paradigm for Brain-Computer Interface

A brain-computer interface (BCI) is a system that conveys messages and commands directly from the human brain to a computer. The BCI system described in this work is based on P300 speller BCI paradigm designed by Farwell and Donchin in 1988. It has been the most widely used and a benchmark in P300 BCI. In this paradigm, a 6x6 matrix of letters and numbers is displayed and subject focuses on a character while different rows and columns flash. The work presented in this paper is an attempt to improve the accuracy of P300 BCI systems by understanding a source of error in this paradigm. It is shown that adjacent rows and columns to the target ones play major role in the error. This can be attributed to human error that when the adjacent row or column to the target one flashes, it attracts subject´s attention and creates the P300.