Comparison of P300 Responses in Auditory, Visual and Audiovisual Spatial Speller BCI Paradigms
This work addresses the problem of evaluating alternative BCI paradigms for BCI-naïve users, but it is incremental as it tests existing methods without introducing new ones.
This study compared auditory, visual, and audiovisual spatial speller BCI paradigms with 16 BCI-naïve subjects using five Japanese hiragana characters, finding that auditory P300 responses showed longer target vs. non-target latencies during training but did not translate to advantages in real-world online BCI experiments.
The aim of this study is to provide a comprehensive test of three spatial speller settings, for the auditory, visual, and audiovisual paradigms. For rigour, the study is conducted with 16 BCI-naïve subjects in an experimental set-up based on five Japanese hiragana characters. Auditory P300 responses give encouragingly longer target vs. non-target latencies during the training phase, however, real-world online BCI experiments in the multimodal setting do not validate this potential advantage. Our case studies indicate that the auditory spatial unimodal paradigm needs further development in order to be a viable alternative to the established visual domain speller applications, as far as BCI-naïve subjects are concerned.