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Beyond cochlear implants: awakening the deafened brain


Cochlear implants have provided hearing to more than 120,000 deaf people. Recent surgical developments include direct electrical stimulation of the brain, bilateral implants and implantation in children less than 1 year old. However, research is beginning to refocus on the role of the brain in providing benefits to implant users. The auditory system is able to use the highly impoverished input provided by implants to interpret speech, but this only works well in those who have developed language before their deafness or in those who receive their implant at a very young age. We discuss recent evidence suggesting that developing the ability of the brain to learn how to use an implant may be as important as further improvements of the implant technology.

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Figure 1: Electrical stimulation of the human auditory system.
Figure 2: Word recognition performance of implant users.
Figure 3: Relationship between the location of cochlea stimulation and the location of neurons tuned preferentially to the stimulating electrode in the primary auditory cortex.
Figure 4: Effect of age of implantation and age of testing on the latency of the P1 auditory evoked cortical response of pre-lingually deafened children.


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Correspondence to David R Moore.

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David Moore is the founder, a director and a shareholder of MindWeavers PLC, a company that makes and sells software for enhancing listening and cognitive processing.

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Moore, D., Shannon, R. Beyond cochlear implants: awakening the deafened brain. Nat Neurosci 12, 686–691 (2009).

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