Ear Electrocardiography With Soft Graphene Textiles for Hearable Applications

Ear-centered physiological recordings offer rich amount of information originated by neural and cardiac activities. This letter investigates possible applications of graphene-based textiles for behind-the-ear discreet and unobtrusive electrocardiography (ECG) monitoring. We systematically analyzed the most suitable electrode positioning for wearable ear ECG and identified the mastoid area behind the ear helix to be suitable for cardiac monitoring, where the collected signals had a mean signal-to-noise ratio of 29.87 dB. Later, graphene textiles were positioned on the selected locations, and we assessed the feasibility of a wearable headphone design for ear ECG through synchronous recording alongside conventional lead-I placement. We anticipate that contributions here are directly applicable to the extraction of heartrate, heart rate variability, and other cardiac P-QRS-T parameters for remote health monitoring, as well as applications requiring vital signs for real-time stress or anxiety classification, such as virtual reality headsets.

I. Introduction

The advancements in point-of-care devices have led to a rapid evolution of mobile healthcare technologies. Especially after the global pandemic, there is a growing interest in remote patient monitoring [1]. Functionalized smart garments can serve as secluded health trackers integrated into everyday clothing, such as bracelets, armbands, gloves, shirts, and headbands [2]. These novel wearable electronic textiles are not only superb for socially well-adjusted health monitoring over extended periods, but also they are extensively applied to wellness and fitness tracking [3].