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Abstract This review examines the role of auditory training on speech adaptation for cochlear implant users. A current limitation of the existing evidence base is the failure to adequately account for wide variability in speech perception outcomes following implantation. While many preimplantation factors contribute to the variance observed in outcomes, formal auditory training has been proposed as a way to maximize speech comprehension benefits for cochlear implant users. We adopt an interdisciplinary perspective and focus on integrating the clinical rehabilitation literature with basic research examining perceptual learning of speech. We review findings on the role of auditory training for improving perception of degraded speech signals in normal hearing listeners, with emphasis on how lexically oriented training paradigms may facilitate speech comprehension when the acoustic input is diminished. We conclude with recommendations for future research that could foster translation of principles of speech learning in normal hearing listeners to aural rehabilitation protocols for cochlear implant patients.
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Characterization and Miniaturization of Silver-Nanoparticle Microcoil via Aerosol Jet Printing Techniques for Micromagnetic Cochlear Stimulation
According to the National Institute of Deafness and other Communication Disorders 2012 report, the number of cochlear implant (CI) users is steadily increasing from 324,000 CI users worldwide. The cochlea, located in the inner ear, is a snail-like structure that exhibits a tonotopic geometry where acoustic waves are filtered spatially according to frequency. Throughout the cochlea, there exist hair cells that transduce sensed acoustic waves into an electrical signal that is carried by the auditory nerve to ultimately reach the auditory cortex of the brain. A cochlear implant bridges the gap if non-functional hair cells are present. Conventional CIs directly inject an electrical current into surrounding tissue via an implanted electrode array and exploit the frequency-to-place mapping of the cochlea. However, the current is dispersed in perilymph, a conductive bodily fluid within the cochlea, causing a spread of excitation. Magnetic fields are more impervious to the effects of the cochlear environment due to the material properties of perilymph and surrounding tissue, demonstrating potential to improve precision. As an alternative to conventional CI electrodes, the development and miniaturization of microcoils intended for micromagnetic stimulation of intracochlear neural elements is described. As a step toward realizing a microcoil array sized for cochlear implantation, human-sized coils were prototyped via aerosol jet printing. The batch reproducible aerosol jet printed microcoils have a diameter of 1800 μm, trace width and trace spacing of 112.5 μm, 12 μm thickness, and inductance values of approximately 15.5 nH. Modelling results indicate that the coils have a combined depolarization–hyperpolarization region that spans 1.5 mm and produce a more restrictive spread of activation when compared with conventional CI.
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- PAR ID:
- 10223431
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 20
- Issue:
- 21
- ISSN:
- 1424-8220
- Page Range / eLocation ID:
- 6087
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/s20216087
