A Wireless, Multielectrode, User-generic Ear EEG Recording System

Recently it has been demonstrated that electroencephalography (EEG) can be recorded from the ear canal (in-ear EEG), opening the door to using discreet earpieces as wearable brain-computer interfaces (BCIs). We present, for the first time to our knowledge, a wireless neural recording platform for recording EEG from the ear canal with dry multielectrode, user-generic earpieces. A low-cost manufacturing process involving vacuum forming and spray coating was developed to improve ear canal contact in a range of users and combined with a 2.5 × 2.5 cm
²
wireless recording system. System performance was evaluated through electrode-skin interface (ESI) impedance characterization and measurement of common EEG signals simultaneously with wet scalp EEG, including eye blinks, alpha waves, and the auditory steady-state response (ASSR) across multiple users. The user-generic ear EEG recorded a mean alpha modulation of 2.17, outperforming the state-of-the-art.