A Dry Electrode for Universal Accessibility to EEG

Abstract Electroencephalography (EEG) measures the brain’s local field potential from the surface of the scalp. This method is useful for studying cognitive processes, neurological states, and medical conditions. Its relative low- cost, ease-of use, and non-invasiveness increase its utility in brain monitoring for both research and medical applications. Unfortunately, the process of acquiring EEG is often not inclusive of all research subjects. EEG typically requires scalp abrasion and application of conductive gels to create a low impedance contact between exposed skin and the electrode tips. This approach is critical to obtaining good signals and reducing artifacts; however, it creates challenges for the hair of Black or African American people. Studies have shown that tightly curled hair (Type 4) of African origin impacts the ability of EEG caps to place electrodes to measure brain activity and the hair’s low absorption of liquid can impact the conductance of the saline solutions used to conduct signal. In addition, people of African origin often select hairstyles with various braiding, locs, or weaving with synthetic hair, which can impede electrode placement and are commonly listed as exclusion criteria for research, thereby excluding people of African origin at higher rates. Furthermore, even when they do participate in collection, EEG technology unsuited to their hair type/style may lead to lower signal-to-noise ratios than on other subjects, resulting in their data being rejected from the study’s analysis, thereby creating an unintentional racial barrier to study inclusion. Quantum Applied Science and Research (QUASAR), Inc. has developed innovative dry active pinned electrodes that work through hair without the need for abrasion or gels and acquire high-quality EEG signals comparable to those from gold-standard wet electrodes. This Phase I SBIR project aims to establish the feasibility of new dry or wet electrode tip designs that address the challenges posed by Type 4 hair types and commonly associated hairstyles. New designs will be tested on phantom mannequin heads and validated on human participants. The overall outcome of this project will be novel EEG electrode designs and systems that will reduce EEG access disparity for people of African origin in medical research and healthcare applications.