Novel Dry Polymer Foam Electrodes for Long-Term EEG Measurement

TLDR

Conventional wet electrodes dominate EEG recording but require skin preparation and conductive gels, which are inconvenient for users. This study proposes a novel dry foam‑based electrode for long‑term EEG measurement to eliminate the need for skin prep and gels. The electrode consists of electrically conductive polymer foam covered with conductive fabric, providing polarization and conductivity while the foam’s conformal geometry maintains low skin‑electrode impedance even during motion. Experimental results show that the dry foam electrode yields superior long‑term EEG performance and is suitable for everyday use.

Abstract

A novel dry foam-based electrode for long-term EEG measurement was proposed in this study. In general, the conventional wet electrodes are most frequently used for EEG measurement. However, they require skin preparation and conduction gels to reduce the skin-electrode contact impedance. The aforementioned procedures when wet electrodes were used usually make trouble to users easily. In order to overcome the aforesaid issues, a novel dry foam electrode, fabricated by electrically conductive polymer foam covered by a conductive fabric, was proposed. By using conductive fabric, which provides partly polarizable electric characteristic, our dry foam electrode exhibits both polarization and conductivity, and can be used to measure biopotentials without skin preparation and conduction gel. In addition, the foam substrate of our dry electrode allows a high geometric conformity between the electrode and irregular scalp surface to maintain low skin-electrode interface impedance, even under motion. The experimental results presented that the dry foam electrode performs better for long-term EEG measurement, and is practicable for daily life applications.