P300 Brain-Computer Interface Performance: A dry electrode study

Most brain-computer interfaces (BCI) are based on one of three types of electroencephalogram (EEG) signals: P300s, steady-state visually evoked potentials (SSVEP), and event-related desynchronization (ERD). EEG is typically recorded non-invasively using active or passive electrodes mounted on the human scalp. The common setup requires conductive electrode gel to get the best entrance impedance and noise ratio. However, electrode gel is inconvenient, uncomfortable, and entails setting problems that are especially pronounced when trained users are not available. Some work has introduced dry electrode systems that do not require gel, but often entail reduced comfort and signal quality. The principal goal of this study was to compare the performance of dry vs. gel-based electrodes in a very common BCI system: P300 spelling. KeywordsBrain Computer Interface; BCI; Dry electrodes; P300 speller;Gel electrodes.