@article{7b035f49356643c09f40ff4e140d5fea,
title = "Cochlear implants: A remarkable past and a brilliant future",
abstract = "The aims of this paper are to (i) provide a brief history of cochlear implants; (ii) present a status report on the current state of implant engineering and the levels of speech understanding enabled by that engineering; (iii) describe limitations of current signal processing strategies; and (iv) suggest new directions for research. With current technology the {"}average{"} implant patient, when listening to predictable conversations in quiet, is able to communicate with relative ease. However, in an environment typical of a workplace the average patient has a great deal of difficulty. Patients who are {"}above average{"} in terms of speech understanding, can achieve 100% correct scores on the most difficult tests of speech understanding in quiet but also have significant difficulty when signals are presented in noise. The major factors in these outcomes appear to be (i) a loss of low-frequency, fine structure information possibly due to the envelope extraction algorithms common to cochlear implant signal processing; (ii) a limitation in the number of effective channels of stimulation due to overlap in electric fields from electrodes; and (iii) central processing deficits, especially for patients with poor speech understanding. Two recent developments, bilateral implants and combined electric and acoustic stimulation, have promise to remediate some of the difficulties experienced by patients in noise and to reinstate low-frequency fine structure information. If other possibilities are realized, e.g., electrodes that emit drugs to inhibit cell death following trauma and to induce the growth of neurites toward electrodes, then the future is very bright indeed.",
keywords = "Auditory prosthesis, Cochlear implant, Cortical plasticity, Deafness, Electrical stimulation, Hearing, Neural prosthesis, Speech perception",
author = "Wilson, {Blake S.} and Michael Dorman",
note = "Funding Information: The Bilger report altered the perspective on CIs at the NIH. Up until that time, only a few, relatively-small projects had been supported by the agency, and most of those did not involve human studies. Indeed, as late as 1978 the NIH rejected an application for funding of human research with CIs on “moral grounds” ( Simmons, 1985 ). The Bilger report demonstrated benefits of CIs, however, and also indicated possibilities for improvements. This had a profound effect at the NIH, and the NIH increased funding for CI research substantially after 1978, including support for human studies. Much of the progress made in the 1980s and afterwards was the direct result of this decision. In particular, work supported through the Neural Prosthesis Program (NPP) at the NIH, first directed by Dr. F. Terry Hambrecht and later by Dr. William J. Heetderks, produced many important innovations in electrode and speech processor designs that remain in use to this day. Additional contributions outside of the NPP were quite important as well, including contributions from investigators in the United States and Australia supported by “regular” (e.g., R01 and Program Project) NIH grants and other sources, and from investigators in Europe who were not supported by the NIH. (Much of the work in Australia was supported both through the NPP and with regular NIH grants, in addition to principal support from the Australian government and private sources.) Funding Information: Some of the findings and thoughts in this paper were first presented in a Special Guest of Honor Address by the first author at the Ninth International Conference on Cochlear Implants and Related Sciences, held in Vienna, Austria, June 14–17, 2006, and with the same title as the present paper. Material also was drawn or adapted from several recent publications ( Dorman and Wilson, 2004; Dorman and Spahr, 2006; Wilson, 2006; Wilson and Dorman, 2007, 2008, in press-a, in press-b ). Work contributing data and ideas to the paper was supported in part by NIH Project N01-DC-2-1002 (to BSW) and its predecessors, all titled “Speech Processors for Auditory Prostheses,” and by NIH project 5R01DC000654 (to MFD) and its predecessors, all titled “Auditory Function and Speech Perception with Cochlear Implants.” The first author is a consultant for MED-EL Medical Electronics GmbH, of Innsbruck, Austria, as its Chief Strategy Advisor. None of the statements in this paper favor that or any other company, and none of the statements pose a conflict of interest. We thank the many subjects who have participated in our studies over the years, and who thereby have made our work possible. The first author also would like to thank Prof. Dr. Wolf-Dieter Baumgartner for his kind invitation to present the talk in Vienna and for his spectacular friendship and partnership in research. We are grateful to the two anonymous reviewers of this paper for their helpful suggestions.",
year = "2008",
month = aug,
doi = "10.1016/j.heares.2008.06.005",
language = "English (US)",
volume = "242",
pages = "3--21",
journal = "Hearing Research",
issn = "0378-5955",
publisher = "Elsevier",
number = "1-2",
}