Is an auditory P300-based Brain-Computer Musical Interface feasible?

One of the most robust ways of building a voluntarily controlled BCI that wouldnt require almost any training on behalf of the user, is through the P300 potential. In this study we implemented and evaluated a simple auditory P300-based musical interface. The interface consists of a dynamic 5-class auditory oddball paradigm. Each stimulus is tuned to a specific note, forming a part of a chord. At the same time each stimulus is mapped to a different chord. The user can change the harmony of the auditory oddball paradigm by mentally counting the occurrences of the desired stimulus. The interface was evaluated on 8 healthy subjects on two scenarios: (i) the audiovisual and (ii) the auditory. The Inter-Onset Interval was set to 220ms and within a trial each stimulus appeared 20 times. As a result a user is able to change the harmony of the interface every 22 seconds. Both scenarios were evaluated on 8 healthy subjects. In the audiovisual scenario the average online accuracy was 80% and in the auditory 44%. According to these results an auditory only P300 based Brain-Computer Musical interface is hardly feasible.