Development and Characterization of a Dry Ear-EEG Sensor With a Generic Flexible Earpiece.

While the sensors of current electroencephalography (EEG) wearables can be miniaturized such that they can be fit into an in-ear hearable device, the brain monitoring based on the state-of-art ear-EEG techniques has several drawbacks such as customization for one individual, time-consuming fabrication process, and short life cycle. To deal with this problem, a new method to design a sensor with one-channel dry electrode embedded in a generic substrate is proposed. The electrical characterizations were evaluated with 15 subjects and five EEG paradigms, in which ear-EEG and conventional scalp EEG were recorded simultaneously. Recordings from the generic dry-contact ear-EEG sensor were compared to conventional scalp EEG recordings. Reliable responses were extracted from the ear-EEG for different paradigms, albeit weaker in amplitude than from scalp EEG. The results demonstrate the feasibility of the designed generic ear-EEG sensor and its potential to achieve sustained, ease-of-use, cost-effective, and off-the-shelf ear-EEG recording use.