Fully objective hearing threshold estimation in cochlear implant users using phase-locking value growth functions
Loading...
Date
2019-03
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier B.V.
Abstract
Cochlear implant users require fitting of electrical threshold and comfort levels for optimal access to sound. In this study, we used single-channel cortical auditory evoked responses (CAEPs) obtained from 20 participants using a Nucleus device. A fully objective method to estimate threshold levels was developed, using growth function fitting and the peak phase-locking value feature. Results demonstrated that growth function fitting is a viable method for estimating threshold levels in cochlear implant users, with a strong correlation (r=0.979, p<0.001) with behavioral thresholds. Additionally, we compared the threshold estimates using CAEPs acquired from a standard montage (Cz to mastoid) against using a montage of recording channels near the cochlear implant, simulating recording from the device itself. The correlation between estimated and behavioural thresholds remained strong (r=0.966, p<0.001), however the recording time needed to be increased to produce a similar estimate accuracy. Finally, a method for estimating comfort levels was investigated, and showed that the comfort level estimates were mildly correlated with behavioral comfort levels (r=0.50, p=0.024).
Description
Keywords
Cochlear implant, Electrical dynamic range, EEG, Objective threshold estimation, Phase-locking value, Cortical response
Citation
Mao, D., H. Innes-Brown, M. A. Petoe, Y. T. Wong, and C. M. McKay. 2019. Fully objective hearing threshold estimation in cochlear implant users using phase-locking value growth functions. Hearing Research. 377: 24-33.