Page 55 - Spring2019

Blake S. Wilson
Address:
2410 Wrightwood Avenue Durham, North Carolina 27705 USA
Also at:
Duke University Chesterfield Building 701 West Main Street
Room 4122, Suite 410 Durham, North Carolina 27701 USA
Email:
blake.wilson@duke.edu
The Remarkable Cochlear Implant and Possibilities for the Next Large Step Forward
The modern cochlear implant is an astonishing success; however,
room remains for improvement and greater access to this already-marvelous technology.
Introduction
The modern cochlear implant (CI) is a surprising achievement. Many experts in otology and auditory science stated categorically that pervasive and highly syn- chronous activation of neurons in the auditory nerve with electrical stimuli could not possibly restore useful hearing for deaf or nearly deaf persons. Their argument in essence was “how can one have the hubris to think that the exquisite machin- ery of the inner ear can be replaced or mimicked with such stimuli?” They had a point!
However, the piece that everyone, or at least most everyone, missed at the begin- ning and for many years thereafter was the power of the brain to make sense of a sparse and otherwise unnatural input and to make progressively better sense of it over time. In retrospect, the job of designers of CIs was to present just enough in- formation in a clear format at the periphery such that the brain could “take over” and do the rest of the job in perceiving speech and other sounds with adequate ac- curacy and fidelity. Now we know that the brain is an important part of the pros- thesis system, but no one to my knowledge knew that in the early days. The brain “saved us” in producing the wonderful outcomes provided by the present-day CIs.
And indeed, most recipients of those present devices use the telephone routinely, even for conversations with initially unfamiliar persons at the other end and even with unpredictable and changing topics. That is a long trip from total or nearly total deafness!
Now, the CI is widely regarded as one of the great advances in medicine and in en- gineering. Recently, for example, the development of the modern CI has been rec- ognized by major international awards such as the 2013 Lasker~DeBakey Clinical Medical Research Award and the 2015 Fritz J. and Dolores H. Russ Prize, just to name two among many more.
As of early 2016, more than half a million persons had received a CI on one side or two CIs, with one for each side. That number of recipients exceeds by orders of magnitude the number for any other neural prosthesis (e.g., retinal or vestibular prostheses). Furthermore, the restoration of function with a CI far exceeds the restoration provided by any other neural prosthesis to date.
Of course, the CI is not the first reported substantial restoration of a human sense. The first report, if I am not mistaken, is in the Gospel of Mark in the New Testa- ment (Mark 7:31-37), which describes the restoration of hearing for a deaf man by Jesus. The CI is the first restoration using technology and a medical intervention and is similarly surprising and remarkable.
https://doi.org/10.1121/AT.2019.15.1.54
©2019 Acoustical Society of America. All rights reserved. volume 15, issue 1 | Spring 2019 | Acoustics Today | 53