Effective approach to character input for novice BCI users

A brain-computer interface (BCI) character input experiment focusing on participants' BCI intelligibility was performed. In theory, a BCI can be operated by anyone if cognitive activity is possible. However, individual differences clearly occur in practice. Therefore, we supposed that this difference was related to BCI intelligibility. In a previous study, BCI experts and BCI novice users were compared. Therefore, in this study, we compared three types of subjects: experts, novice users, and novice users who received pre-guidance. The preguidance provided instructions about the tips, tricks, and traps of BCI operation. As a result, the classification rate was 80% or more, in all groups. However, high accuracy was only produced by the group that had BCI intelligibility. The accuracy results for novice users who did not receive pre-guidance was 13.6%, the results for experts was 62.4%, and the results for novice users who received pre-guidance was 71.1%. From these results, the effectiveness of pre-guidance for a novice user was demonstrated.