The ear: Gateway to the brain. Exploring the Feasibility of a novel in-ear electroencephalography device in an auditory brain-computer interface

A brain-computer interface (BCI) enables communication using signals directly from the brain. Electroencephalography (EEG) is often used to collect these signals and commonly involves scalp-based electrodes which are conspicuous, and uncomfortable over long periods. In-ear EEG devices address many of these shortcomings and can discreetly measure brain activity from within the ear canal. We designed an in-ear EEG device usable with a commercial EEG amplifier and tested this device in an auditory BCI involving auditory evoked potentials (AEPs) and the auditory steady state response (ASSR). Using scalp electrodes, AEP accuracy was ~ 79 %, and focus-modulated ASSR accuracies were above chance in 3 of 7 participants. Equivalent neural responses were evidenced in the in-ear recordings. However, classification outcomes were poor, reflecting challenges with in-ear measurement and the reduced number of electrodes. This study highlights the need for further research into device morphologies and paradigms for in-ear EEG.M.A.S