Cochlear implant

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Cochlear implant
Blausen 0244 CochlearImplant 01.png
Cochlear implant

A cochlear implant (CI) is a surgically implanted neuroprosthesis that provides a person who has bilateral moderate-to-profound sensorineural hearing loss with sound perception and improved speech understanding in both quiet and noise.[1][2][3] The CI bypasses the normal acoustic hearing process by providing direct electrical stimulation to the auditory nerve.[2] Through everyday listening and effective auditory training, both children and adults learn to interpret those signals as speech and sound, thus restoring functional hearing.[4][5][6]

The implant has two main components. The outside component is generally worn behind the ear, but could also be attached to clothing, for example, in young children. This component, the sound processor, contains microphones, electronics that include digital signal processor (DSP) chips, battery, and a coil that transmits a signal to the implant across the skin. The inside component, the actual implant, has a coil to receive signals, electronics, and an array of electrodes which is placed into the cochlea, which stimulate the cochlear nerve.[7]

The surgical procedure is performed under general anesthesia. Surgical risks are minimal but can include tinnitus, facial nerve bruising and dizziness.

From the early days of implants in the 1970s and the 1980s, speech perception via an implant has steadily increased. Many users of modern implants gain reasonable to good hearing and speech perception skills post-implantation, especially when combined with lipreading.[8][9] One of the challenges that remain with these implants is that hearing and speech understanding skills after implantation show a wide range of variation across individual implant users. Factors such as age of implantation, parental involvement and education level, duration and cause of hearing loss, how the implant is situated in the cochlea, the overall health of the cochlear nerve, but also individual capabilities of re-learning are considered to contribute to this variatio.[10][11][12]

Despite providing the ability for hearing and oral speech communication to children and adults with severe to profound hearing loss, there is also controversy around the devices. Much of the strongest objection to cochlear implants has come from the Deaf community. For some in the Deaf community, cochlear implants are an affront to their culture, which as some view it, is a minority threatened by the hearing majority.[13]


An infant with a cochlear implant

André Djourno and Charles Eyriès invented the original cochlear implant in 1957. This original design distributed stimulation using a single channel.[14]

William House also invented a cochlear implant in 1961.[15] In 1964, Blair Simmons and Robert J. White implanted a single-channel electrode in a patient's cochlea at Stanford University.[16] However, research indicated that these single-channel cochlear implants were of limited usefulness because they cannot stimulate different areas of the cochlea at different times to allow differentiation between low and mid to high frequencies as required for detecting speech.[17]

NASA engineer Adam Kissiah started working in the mid-1970s on what could become the modern cochlear implant. Kissiah used his knowledge learned while working as an electronics instrumentation engineer at NASA. This work took place over three years, when Kissiah would spend his lunch breaks and evenings in Kennedy's technical library, studying the impact of engineering principles on the inner ear. In 1977, NASA helped Kissiah obtain a patent for the cochlear implant; Kissiah later sold the patent rights.[18]

The modern multi-channel cochlear implant was independently developed and commercialized by two separate teams—one led by Graeme Clark in Australia and another by Ingeborg Hochmair and her future husband, Erwin Hochmair in Austria, with the Hochmairs' device first implanted in a person in December 1977 and Clark's in August 1978.[19]


Cochlear implants bypass most of the peripheral auditory system which receives sound and converts that sound into movements of hair cells in the cochlea; the deflection of stereocilia causes an influx of potassium ions into the hair cells, and the depolarisation in turn stimulates calcium influx, which increases release of the neurotransmitter, glutamate. Excitation of the cochlear nerve send signals to the brain, which creates the experience of sound. Instead, the devices pick up sound and digitize it, convert that digitized sound into electrical signals, and transmit those signals to electrodes embedded in the cochlea. The electrodes electrically stimulate the cochlear nerve, causing it to send signals to the brain.[20][21][22]

There are several systems available, but generally they have the following components:[20][22]


  • one or more microphones that pick up sound from the environment
  • a speech processor which selectively filters sound to prioritize audible speech
  • a transmitter that sends power and the processed sound signals across the skin to the internal device by radio frequency transmission


  • a receiver/stimulator, which receives signals from the speech processor and converts them into electric impulses
  • an electrode array embedded in the cochlea

A totally implantable cochlear implant (TICI) is currently in development. This new type of cochlear implant incorporates all the current external components of an audio processor into the internal implant. The lack of external components makes the implant invisible from the outside and also means it is less likely to suffer damage and breakages.[23]

Surgical procedure[edit]

Traditional surgical technique[edit]

Implantation of children and adults can be done safely with few surgical complications and most individuals will undergo outpatient surgery.[24][25]

The surgical procedure most often used to implant the device is called mastoidectomy with facial recess approach (MFRA).[22]

The procedure is usually done under general anesthesia. Complications of the procedure are rare, but include mastoiditis, otitis media (acute or with effusion), shifting of the implanted device requiring a second procedure, damage to the facial nerve, damage to the chorda tympani, and wound infections.[26]

The rate of complications is about 12% for minor complications and 3% for major complications; major complications include infections, facial paralysis, and device failure. To avoid the risk of bacterial meningitis, which while low is about thirty times as high compared to people who don't undergo CI procedures, the FDA recommends vaccination prior to the procedure. The rate of transient facial nerve palsy is estimated to be approximately 1%. Device failure requiring reimplantation is estimated to occur 2.5–6% of the time. Up to one-third of people experience disequilibrium, vertigo, or vestibular weakness lasting more than one week after the procedure; in people under 70 these symptoms generally resolve over weeks to months, but in people over 70 the problems tend to persist.[22]

In the past cochlear implants were only approved for people who were deaf in both ears; as of 2014 a cochlear implant had been used experimentally in some people who had acquired deafness in one ear after they had learned how to speak, and none who were deaf in one ear from birth; clinical studies as of 2014 had been too small to draw generalizations.[27]

Alternative surgical technique[edit]

Other approaches, such as going through the suprameatal triangle, are used. A systematic literature review published in 2016 found that studies comparing the two approaches were generally small, not randomized, and retrospective so were not useful for making generalizations; it is not known which approach is safer or more effective.[26]

Endoscopic cochlear implantation[edit]

With the increased utilization of endoscopic ear surgery as popularized by professor Tarabichi, there have been multiple published reports on the use of endsocopic technique in cochlear impant surgery.[28] However, this has been motivated by marketing and there is clear indication of increased morbidity associated with this technique as reported by the pioneer of endoscopic ear surgery.[29]


A 2011 AHRQ review of the evidence of the effectiveness of CI in people with bilateral hearing loss — the device's primary use — found low to moderate quality data[according to whom?] that showed speech perception in noisy conditions was much better for people who had implants in both ears done at the same time compared to people who had only one. The data also showed that no conclusions could be drawn about changes in speech perception in quiet conditions and health-related quality of life. There was only one good study[according to whom?] comparing implanting implants in both ears at the same time to implanting them sequentially; this study found that in the sequential approach, the second implantation made no change, or made things worse.[30]

Several 2010 and 2012 reviews found that the ability to communicate in spoken language was better the earlier the implantation was performed. The reviews also found that, overall, while cochlear implants provide open set speech understanding for the majority of implanted profoundly hearing-impaired children, the efficacy of cochlear implants is highly variable, and depends on factors such as parental involvement, parental education level, and amount of spoken language exposure.[31][32][33]

A 2015 review examined whether CI implantation to treat people with bilateral hearing loss had any effect on tinnitus. This review found the quality of evidence to be poor and the results variable: overall total tinnitus suppression rates varied from 8% to 45% of people who received CI; decrease of tinnitus was seen in 25% to 72%, of people; for 0% to 36% of the people there was no change; increase of tinnitus occurred in between 0% to 25% of patients; and, in between 0 and 10% of cases, people who did not have tinnitus before the procedure, got it.[34]

A 2015 literature review on the use of CI for people with auditory neuropathy spectrum disorder found that, as of that date, description and diagnosis of the condition was too heterogeneous to make clear claims about whether CI is a safe and effective way to manage it.[35]

A 2016 research study found that age at implantation was highly correlated with post-operative speech understanding performance for various test measures. In this study, people who were implanted at age 65 or older performed significantly worse on speech perception testing in quiet and in noisy conditions compared to younger CI users. The deleterious effects of aging on central auditory processing abilities are thought to play an important role in impacting an individual's speech perception abilities with CI. Prolonged duration of deafness is another factor that is thought to have a negative impact on overall speech understanding outcomes for CI users. However, this particular study found no statistical difference in the speech understanding abilities of CI patients over 65 who had been hearing impaired for 30 years or more prior to implantation.[36] In general, outcomes for CI patients are dependent upon the individual's level of motivation, expectations, exposure to speech stimuli and consistent participation in aural rehabilitation programs.

A 2016 systematic review of CI for people with unilateral hearing loss (UHL) found that of the studies conducted and published, none were randomized, only one evaluated a control group, and no study was blinded. After eliminating multiple uses of the same subjects, the authors found that 137 people with UHL had received a CI.[37] While acknowledging the weakness of the data, the authors found that CI in people with UHL improves sound localization compared with other treatments in people who lost hearing after they learned to speak; in the one study that examined this, CI did improve sound localization in people with UHL who lost hearing before learning to speak.[37] It appeared to improve speech perception and to reduce tinnitus.[37]

Society and culture[edit]


As of October 2010, approximately 188,000 individuals had been fitted with cochlear implants.[38] As of December 2012, the same publication cited approximately 324,000 cochlear implant devices having been surgically implanted. In the U.S., roughly 58,000 devices were implanted in adults and 38,000 in children.[21] As of 2016, the Ear Foundation in the United Kingdom, estimates the number of cochlear implant recipients in the world to be about 600,000.[39]


In the United States, the overall cost of getting cochlear implants was about $100,000 as of 2017.[40] Some or all of this may be covered by health insurance. In the United Kingdom, the NHS covers cochlear implants in full, as does Medicare in Australia, and the Department of Health[41] in Ireland, Seguridad Social in Spain, Sécurité Sociale in France[42] and Israel, and the Ministry of Health or ACC (depending on the cause of deafness) in New Zealand. According to the US National Institute on Deafness and Other Communication Disorders, the estimated total cost is $60,000 per person implanted.[citation needed]

A study by Johns Hopkins University determined that for a three-year-old child who receives them, cochlear implants can save $30,000 to $50,000 in special-education costs for elementary and secondary schools as the child is more likely to be mainstreamed in school and thus use fewer support services than similarly deaf children.[43]


As of 2013, the three cochlear implant devices approved for use in the US were manufactured by Cochlear Limited (Australia), Advanced Bionics (a division of Sonova) and MED-EL (Austria). In Europe, Africa, Asia, South America, and Canada, an additional device manufactured by Neurelec (France, a division of William Demant) was available. A device made by Nurotron (China) was also available in some parts of the world. Each manufacturer has adapted some of the successful innovations of the other companies to its own devices. There is no consensus that any one of these implants is superior to the others. Users of all devices report a wide range of performance after implantation.[citation needed]

Criticism and controversy[edit]

Much of the strongest objection to cochlear implants has come from within the Deaf community, some of whom are pre-lingually deaf people whose first language is a sign language. For some in the Deaf community, cochlear implants are an affront to their culture, which, as they view it, is a minority threatened by the hearing majority.[13] This is an old problem for the Deaf community, going back as far as the 18th century with the argument of manualism vs. oralism. This is consistent with medicalisation and the standardisation of the "normal" body in the 19th century when differences between normal and abnormal began to be debated.[44] It is important to consider the sociocultural context, particularly in regards to the Deaf community, which has its own unique language and culture.[45] This accounts for the cochlear implant being seen as an affront to their culture, as many do not believe that deafness is something that needs to be cured. However, it has also been argued that this does not necessarily have to be the case: the cochlear implant can act as a tool deaf people can use to access the "hearing world" without losing their Deaf identity.[45]

Cochlear implants for congenitally deaf children are most effective when implanted at a young age.[46] Evidence shows that Deaf children of Deaf parents (or with fluent signers as daily caregivers) learn signed language as effectively as hearing peers. Some Deaf-community advocates recommend that all Deaf children should learn sign language from birth,[47] but more than 90% of deaf children are born to hearing parents. Since it takes years to become fluent in sign language, deaf children who grow up without amplification such as hearing aids or cochlear implants will not have daily access to fluent language models in households without fluent signers.

Critics of cochlear implants from Deaf cultures also assert that the cochlear implant and the subsequent therapy often become the focus of the child's identity at the expense of language acquisition and ease of communication in sign language and Deaf identity. They believe that measuring a child's success only by their mastery of speech will lead to a poor self-image as "disabled" (because the implants do not produce normal hearing) rather than having the healthy self-concept of a proudly Deaf person.[48] However, these assertions are not supported by research. The first children to receive cochlear implants as infants are only in their 20s (as of 2020), and anecdotal evidence points to a high level of satisfaction in this cohort, most of whom don't consider their deafness their primary identity.[49]

Children with cochlear implants are most likely to be educated with listening and spoken language, without sign language and are often not educated with other Deaf children who use sign language.[50] Cochlear implants have been one of the technological and social factors implicated in the decline of sign languages in the developed world.[51] Some Deaf activists have labeled the widespread implantation of children as a cultural genocide.[52]

As the trend for cochlear implants in children grows, Deaf-community advocates have tried to counter the "either or" formulation of oralism vs. manualism with a "both and" or "bilingual-bicultural"[53] approach; some schools are now successfully integrating cochlear implants with sign language in their educational programs.[54] However, there is no clinical evidence suggesting that sign language supports the development of spoken language, while there is significant clinical evidence suggesting that deaf children (of hearing parents) who use no sign language or very little sign language develop better spoken language skills than those children who use both sign and speech. [55]

See also[edit]


  1. ^ "NCD - Cochlear Implantation (50.3)". Retrieved 2021-11-22.
  2. ^ a b "Cochlear Implants". NIDCD. Retrieved 2021-11-22.
  3. ^ Buchman, Craig A.; Gifford, René H.; Haynes, David S.; Lenarz, Thomas; O’Donoghue, Gerard; Adunka, Oliver; Biever, Allison; Briggs, Robert J.; Carlson, Matthew L.; Dai, Pu; Driscoll, Colin L. (2020-10-01). "Unilateral Cochlear Implants for Severe, Profound, or Moderate Sloping to Profound Bilateral Sensorineural Hearing Loss: A Systematic Review and Consensus Statements". JAMA Otolaryngology–Head & Neck Surgery. 146 (10): 942–953. doi:10.1001/jamaoto.2020.0998. ISSN 2168-6181. PMID 32857157. S2CID 221359090.
  4. ^ Rayes, Hanin; Al, -Malky Ghada; Vickers, Deborah (2019-05-21). "Systematic Review of Auditory Training in Pediatric Cochlear Implant Recipients". Journal of Speech, Language, and Hearing Research. 62 (5): 1574–1593. doi:10.1044/2019_JSLHR-H-18-0252. PMID 31039327. S2CID 141503740.
  5. ^ Henshaw, Helen; Ferguson, Melanie A. (2013-05-10). "Efficacy of Individual Computer-Based Auditory Training for People with Hearing Loss: A Systematic Review of the Evidence". PLOS ONE. 8 (5): e62836. Bibcode:2013PLoSO...862836H. doi:10.1371/journal.pone.0062836. ISSN 1932-6203. PMC 3651281. PMID 23675431.
  6. ^ Sweetow, Robert; Palmer, Catherine V. (July 2005). "Efficacy of individual auditory training in adults: a systematic review of the evidence". Journal of the American Academy of Audiology. 16 (7): 494–504. doi:10.3766/jaaa.16.7.9. ISSN 1050-0545. PMID 16295236.
  7. ^ Naples, James G.; Ruckenstein, Michael J. (February 2020). "Cochlear Implant". Otolaryngologic Clinics of North America. 53 (1): 87–102. doi:10.1016/j.otc.2019.09.004. PMID 31677740. S2CID 207890377.
  8. ^ Clark, Graeme M. (April 2015). "The Multi-Channel Cochlear Implant: Multi-Disciplinary Development of Electrical Stimulation of the Cochlea and the Resulting Clinical Benefit". Hearing Research. 322: 4–13. doi:10.1016/j.heares.2014.08.002. PMID 25159273.
  9. ^ Shannon, Robert V. (February 2012). "Advances in Auditory Prostheses". Current Opinion in Neurology. 25 (1): 61–66. doi:10.1097/WCO.0b013e32834ef878. PMC 4123811. PMID 22157109.
  10. ^ Blamey, Peter; Artieres, Françoise; Başkent, Deniz; Bergeron, François; Beynon, Andy; Burke, Elaine; Dillier, Norbert; Dowell, Richard; Fraysse, Bernard; Gallégo, Stéphane; Govaerts, Paul J.; Green, Kevin; Huber, Alexander M.; Kleine-Punte, Andrea; Maat, Bert; Marx, Mathieu; Mawman, Deborah; Mosnier, Isabelle; O'Connor, Alec Fitzgerald; O'Leary, Stephen; Rousset, Alexandra; Schauwers, Karen; Skarzynski, Henryk; Skarzynski, Piotr H.; Sterkers, Olivier; Terranti, Assia; Truy, Eric; Van de Heyning, Paul; Venail, Fréderic; Vincent, Christophe; Lazard, Diane S. (2013). "Factors Affecting Auditory Performance of Postlinguistically Deaf Adults Using Cochlear Implants: An Update with 2251 Patients" (PDF). Audiology and Neurotology. 18 (1): 36–47. doi:10.1159/000343189. PMID 23095305. S2CID 4668675.
  11. ^ Başkent, D.; Gaudrain, E.; Tamati, T.N.; Wagner, A. (2016). Perception and psychoacoustics of speech in cochlear implant users, in Scientific Foundations of Audiology: Perspectives from Physics, Biology, Modeling, and Medicine, Eds. A.T. Cacace, E. de Kleine, A.G. Holt, and P. van Dijk. San Diego, CA, USA: Plural Publishing, Inc. pp. 285–319.
  12. ^ Pisoni, David B.; Kronenberger, William G.; Harris, Michael S.; Moberly, Aaron C. (December 2017). "Three challenges for future research on cochlear implants". World Journal of Otorhinolaryngology - Head and Neck Surgery. 3 (4): 240–254. doi:10.1016/j.wjorl.2017.12.010. PMC 5956139. PMID 29780970.
  13. ^ a b "The Cochlear Implant Controversy, Issues And Debates". CBS News. NEW YORK. September 4, 2001. Retrieved 2021-05-08.
  14. ^ Svirsky, Mario (2017). "Cochlear implants and electronic hearing". Physics Today. 70 (8): 52–58. Bibcode:2017PhT....70h..52S. doi:10.1063/PT.3.3661. ISSN 0031-9228.
  15. ^ Martin, Douglas (December 15, 2012). "Dr. William F. House, Inventor of Pioneering Ear-Implant Device, Dies at 89". The New York Times. Retrieved 2012-12-16.
  16. ^ Mudry, A; Mills, M (May 2013). "The early history of the cochlear implant: a retrospective". JAMA Otolaryngology–Head & Neck Surgery. 139 (5): 446–53. doi:10.1001/jamaoto.2013.293. PMID 23681026.
  17. ^ Clark, Graeme (2009). "The multi-channel cochlear implant: past, present and future perspectives". Cochlear Implants International. 10 Suppl 1: 2–13. doi:10.1179/cim.2009.10.Supplement-1.2. ISSN 1754-7628. PMID 19127562. S2CID 30532987.
  18. ^ NASA (2003). NASA space station. Washington, DC: U.S. Government Printing. Archived from the original on 2003-10-18.
  19. ^ "2013 Lasker~DeBakey Clinical Medical Research Award: Modern cochlear implant". The Lasker Foundation. Retrieved 14 July 2017.
  20. ^ a b Roche JP, Hansen MR (2015). "On the Horizon: Cochlear Implant Technology". Otolaryngol. Clin. North Am. 48 (6): 1097–116. doi:10.1016/j.otc.2015.07.009. PMC 4641792. PMID 26443490.
  21. ^ a b NIH Publication No. 11-4798 (2013-11-01). "Cochlear Implants". National Institute on Deafness and Other Communication Disorders. Retrieved February 18, 2016.
  22. ^ a b c d Yawn R, Hunter JB, Sweeney AD, Bennett ML (2015). "Cochlear implantation: a biomechanical prosthesis for hearing loss". F1000Prime Rep. 7: 45. doi:10.12703/P7-45. PMC 4447036. PMID 26097718.
  23. ^ Cohen, Noel (April 2007). "The Totally Implantable Cochlear Implant". Ear and Hearing. 28 (2): 100S–101S. doi:10.1097/AUD.0b013e31803150f4. ISSN 1538-4667. PMID 17496658. S2CID 38696317.
  24. ^ Hoff, Stephen; Ryan, Maura; Thomas, Denise; Tournis, Elizabeth; Kenny, Hannah; Hajduk, John; Young, Nancy M. (April 2019). "Safety and Effectiveness of Cochlear Implantation of Young Children, Including Those With Complicating Conditions". Otology & Neurotology. 40 (4): 454–463. doi:10.1097/MAO.0000000000002156. ISSN 1531-7129.
  25. ^ "Hearing aids vs cohclear implants: What's the difference?". 2021-05-28. Retrieved 2021-12-01.
  26. ^ a b Bruijnzeel H; et al. (2016). "Systematic Review on Surgical Outcomes and Hearing Preservation for Cochlear Implantation in Children and Adults". Otolaryngology–Head and Neck Surgery. 154 (4): 586–96. doi:10.1177/0194599815627146. PMID 26884363. S2CID 25594951.
  27. ^ Tokita, J; Dunn, C; Hansen, MR (October 2014). "Cochlear implantation and single-sided deafness". Current Opinion in Otolaryngology & Head and Neck Surgery. 22 (5): 353–8. doi:10.1097/moo.0000000000000080. PMC 4185341. PMID 25050566.
  28. ^ Rajan, Philip; Teh, Hui Mon; Prepageran, Narayanan; Kamalden, Tengku Izam Tengku; Tang, Ing Ping (2017-12-01). "Endoscopic Cochlear Implant: Literature Review and Current Status". Current Otorhinolaryngology Reports. 5 (4): 268–274. doi:10.1007/s40136-017-0164-2. ISSN 2167-583X. S2CID 80330932.
  29. ^ Tarabichi, Muaaz; Nazhat, Omar; Kassouma, Jamal; Najmi, Murtaza (2016). "Endoscopic cochlear implantation: Call for caution". The Laryngoscope. 126 (3): 689–692. doi:10.1002/lary.25462. ISSN 1531-4995. PMID 26154143. S2CID 24799811.
  30. ^ Raman, G.; Lee, J.; Chung, M.; Gaylor, J. M.; Sen, S.; Rao, M.; Lau, J.; Poe, D. S.; Neault, M. W. (17 June 2011). Raman, G.; Lee, J.; Chung, M.; Gaylor, J. M.; Sen, S.; Rao, M.; Lau, J.; Poe, D. S.; Neault, M. W. (eds.). Effectiveness of Cochlear Implants in Adults With Sensorineural Hearing Loss [Internet] (PDF). Rockville (MD): Agency for Healthcare Research and Quality. PMID 25927131.
  31. ^ Kral, Andrej; O'Donoghue, Gerard M. (2010). "Profound Deafness in Childhood". New England Journal of Medicine. 363 (15): 1438–50. doi:10.1056/NEJMra0911225. PMID 20925546. S2CID 13639137.
  32. ^ Niparko, John K (2010). "Spoken Language Development in Children Following Cochlear Implantation". JAMA. 303 (15): 1498–506. doi:10.1001/jama.2010.451. PMC 3073449. PMID 20407059.
  33. ^ Ganek, Hillary; Robbins, Amy McConkey; Niparko, John K. (2012). "Language Outcomes After Cochlear Implantation". Otolaryngologic Clinics of North America. 45 (1): 173–185. doi:10.1016/j.otc.2011.08.024. PMID 22115689.
  34. ^ Ramakers GG, van Zon A, Stegeman I, Grolman W (2015). "The effect of cochlear implantation on tinnitus in patients with bilateral hearing loss: A systematic review". Laryngoscope. 125 (11): 2584–92. doi:10.1002/lary.25370. PMID 26153087. S2CID 19088970.
  35. ^ Harrison RV, Gordon KA, Papsin BC, Negandhi J, James AL (2015). "Auditory neuropathy spectrum disorder (ANSD) and cochlear implantation". International Journal of Pediatric Otorhinolaryngology. 79 (12): 1980–7. doi:10.1016/j.ijporl.2015.10.006. PMID 26545793.
  36. ^ Beyea, Jason A.; McMullen, Kyle P.; Harris, Michael S.; Houston, Derek M.; Martin, Jennifer M.; Bolster, Virginia A.; Adunka, Oliver F.; Moberly, Aaron C. (October 2016). "Cochlear Implants in Adults: Effects of Age and Duration of Deafness on Speech Recognition". Otology & Neurotology. 37 (9): 1238–1245. doi:10.1097/MAO.0000000000001162. ISSN 1537-4505. PMID 27466894. S2CID 10143665.
  37. ^ a b c Cabral Junior F, Pinna MH, Alves RD, Malerbi AF, Bento RF (2016). "Cochlear Implantation and Single-sided Deafness: A Systematic Review of the Literature". International Archives of Otorhinolaryngology. 20 (1): 69–75. doi:10.1055/s-0035-1559586. PMC 4687988. PMID 26722349.
  38. ^ "NIH Fact Sheets - Cochlear Implants". Archived from the original on 2011-10-22. Retrieved 2018-09-14.
  39. ^ "Cochlear Implant Information Sheet". The Ear Foundation. Archived from the original on 2017-07-11. Retrieved 2018-09-14.
  40. ^ "Cochlear Implants". American Academy of Otolaryngology–Head and Neck Surgery. 21 April 2014. Archived from the original on 24 August 2017. Retrieved 12 May 2017.
  41. ^ "Beaumont Hospital - Cochlear Implant - How to Refer".
  42. ^ "Coût de l'implant cochléaire". (in French). Centre d'Information sur la Surdité et l'Implant Cochléaire.
  43. ^ John M. Williams (2000-05-05). "Do Health-Care Providers Have to Pay for Assistive Tech?". Business Week. Retrieved 2009-10-25.
  44. ^ Lock, M. and Nguyen, V-K., An Anthropology of Biomedicine, Oxford, Wiley-Blackwell, 2010.[page needed]
  45. ^ a b Power D (2005). "Models of deafness: cochlear implants in the Australian daily press". Journal of Deaf Studies and Deaf Education. 10 (4): 451–9. doi:10.1093/deafed/eni042. PMID 16000690.
  46. ^ Paul Oginni (2009-11-16). "UCI Research with Cochlear Implants No Longer Falling on Deaf Ears". New University. Retrieved 2009-11-18.
  47. ^ Hall, Matthew L.; Hall, Wyatte C.; Caselli, Naomi K. (2019). "Deaf children need language, not (Just) speech". First Language. 39 (4): 367–395. doi:10.1177/0142723719834102. S2CID 140083091.
  48. ^ NAD Cochlear Implant Committee. "Cochlear Implants". Archived from the original on 2007-02-20.
  49. ^ Hicks, Kerri (2016-08-05). "We Are Not Language Deprived".
  50. ^ Ringo, Allegra (August 9, 2013). "Understanding Deafness: Not Everyone Wants to Be 'Fixed'". The Atlantic.
  51. ^ Johnston, T (2004). "W(h)ither the deaf community? Population, genetics, and the future of Australian sign language". American Annals of the Deaf. 148 (5): 358–75. doi:10.1353/aad.2004.0004. PMID 15132016. S2CID 21638387.
  52. ^ Christiansen, John B.; Leigh, Irene W.; Spencer, Patricia Elizabeth; Lucker, Jay R. (2001). Cochlear implants in children : ethics and choices ([Online-Ausg.] ed.). Washington, D.C.: Gallaudet University Press. pp. 304–305. ISBN 9781563681165.
  53. ^ De Vera, Neyrchel; Dharer, Yaser. "Bilingual-Bicultural Education of Deaf/Hard-of- Hearing Children". deafed. Retrieved 9 February 2020.
  54. ^ Denworth, Lydia (April 25, 2014). "Science Gave My Son the Gift of Sound". Time.
  55. ^ Geers, Anne Ph.D. (2017-07-01). "Early Sign Language Exposure and Cochlear Implantation Benefits".
  56. ^ 3D microscaffold cochlear implant

Further reading[edit]

External links[edit]