electrode-skin impedance model for in-ear electrophysiology accounting for cerumen (earwax) and electrodermal response
Name: Akshay Paul
Grad Year: 2018
Conventional electroencephalography (EEG) requires placement of several electrode sensors on the scalp and, accompanied by lead wires and bulky instrumentation, makes for an uncomfortable experience. Recent efforts in miniaturization and system integration have enabled smaller systems, such as wearable, in-ear EEG devices that are gaining popularity for their unobtrusive form factor. Although in-ear EEG has been demonstrated in recent works, dynamics of the ear and ear canal that directly effect electrophysiological measurements have been largely ignored. Here, we present a quantitative analysis of electrode-skin impedance for in-ear EEG that accounts for cerumen (earwax) and electrodermal response. Custom fitted earmolds with 16 embedded electrodes were developed to map the skin conductance in the ear canal of 3 subjects. In the presence of cerumen, the calculated average conductivity of the ear canal was 73% less than canals removed of cerumen. Electrodermal activity was also found to play a role in electrode-skin impedance, increasing SC by up to 300% in response to certain stimuli. The better understanding of the dynamics of in-ear conditions may improve consistency and accuracy of in-ear electrophysiology.
Industry Application Area(s)
Electronics/Photonics | Life Sciences/Medical Devices & Instruments