Recent Advances in Polymer-based Thin-film Electrode for ECoG Applications

Abstract

Electrocorticography (ECoG) has garnered widespread attention due to its superior signal resolution compared to conventional electroencephalogram (EEG). While ECoG signal acquisition entails invasiveness, the invasive rigid electrode inevitably inflicts damage on brain tissue. Polymer electrodes that combine conductivity and transparency have garnered great interest, due to that they not only facilitate high-quality signal acquisition but also provide additional insights while preserving the health of the brain, positioning them as the future frontier in the BCI. This review summarizes the multifaceted functions of polymers in ECoG thin-film electrode for BCI. We present the abilities of sensitive and structural polymers focusing on the impedance reduce, signal quality improvement, good flexibility, and transparency. Typically, two sensitive polymers and four structural polymers are detailed analyzed in properties for ECoG electrode. Moreover, the underlying mechanism of polymer-based electrode in signal quality enhancement are also revealed. Finally, the remaining challenges and perspectives are also discussed.