More on this and related topics

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CI Sound Demonstration

July 2000

One of the questions often asked of people who use hearing aids or cochlear implants is what things sound like using those devices. I'm not really sure I believe that people who don't use them can really know how they sound, but there are demonstrations available of how scientists think they sound.

One such demonstration of the sound quality of cochlear implants is available at: www.utdallas.edu/~loizou/cimplants/. This site provides demonstrations of how implants might sound with different numbers of channels. It also demonstrates how the depth of electrode insertion influences the sound quality. Very interesting for those of you with usable hearing, or for your hearing friends and family to get some idea of the sound quality a cochlear implant can provide.

BTW, there's lots of other good information at this site. While you're there, take a minute and poke around.

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MEMS CI on the Way?

October 2003

Editor: Ever heard of MEMS? Well, neither had I, until I saw an article in Fortune talking about potential future applications of this technology. "MEMS" is the abbreviation for Micro-Electro-Mechanical Systems, and it's creating quite a stir within the experimental medical community. One of the potential applications is a second-generation cochlear implant. Here are a couple of excerpts from the Fortune article. For the full article, please point your browser to: http://www.forbes.com/asap/2001/0402/052a.html

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"Deafness is a treatable situation," proclaims Kensall "Ken" Wise, professor of electrical engineering and computer science at the University of Michigan at Ann Arbor. "In the next 20 years, most deafness will disappear." With funding from the National Institutes of Health (NIH), Wise is developing a second-generation cochlear implant based on MEMS that he expects to be commercialized in about five years.

The first MEMS neural implant to reach the market will likely be for deafness. At the University of Michigan, Wise's device uses a MEMS electrode to interface with neurons responsible for translating auditory signals. The array is threaded into the inner ear of a deaf person, where it relays "sound" to the brain. Currently, non-MEMS devices have been implanted in about 30,000 people, but Wise expects MEMS to improve hearing sensitivity, enabling someone to pick out speech in a crowded room or hear a much more natural version of music.

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CI Technology Timeline

January 2006

Here's a timeline of inventions and discoveries on the road to today's cochlear implants. The timeline begins in 1800, and continues through 2004.  Full Story

Sounds of innovation

March 2006

A group of University scientists recently developed a new hearing aid device which will allow users to hear a higher-quality sound than existing technology permits. The device is called a cochlear implant - a type of hearing aid implanted in a spiraled, snail-like structure in the ear called the cochlea. Full Story  

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Light-Based CI Might Outperform Today's Technology

August 2007

About 100,000 profoundly deaf people now hear with cochlear implants, which work by stimulating the auditory nerve with a string of electrodes implanted in the inner ear. While the devices enable many users to converse easily and use telephones, they still fall short of restoring normal hearing. Now scientists at Northwestern University are exploring whether laser-based implants could one day outperform today's electrical version. The mammalian ear uses neural firing rates as one way of encoding sound. As part of a project funded by the National Institute for Deafness and Other Communication Disorders (NIDCD), Claus-Peter Richter and his colleagues at Northwestern have demonstrated that they can control firing rates in the auditory nerve of animals using infrared laser radiation. They are now trying to establish that it's safe to use for long periods of time and that it can manipulate neural firing rates with enough precision to send useful information to the brain.  Full Story

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Doctor Maps CI from Halfway Around the World

March 2008

Through the power of Internet technology, medical experts in New York have switched on an inner-ear device, allowing a man in Uganda to hear for the first time in two years. Activating the device from halfway around the world is a first, and highlights a trailblazing way in which the growing realm of telemedicine - conducting medical procedures from remote locations - can enhance the lives of people in struggling nations.  Full Story

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Should you consider upgrading the INTERNAL CI components?

March 2008

YOU could call it the upgrader's dilemma. When it comes to buying a new mobile phone, computer or DVD player, should you buy the latest and greatest model now, since it offers new features that your old model lacks? Or should you wait for the next version of the technology that will be along next year and threatens to make today's gear seem suddenly old-fashioned? Now imagine that upgrading the item in question requires you to have surgery. That, in a nutshell, is the predicament that people with cochlear implants may soon be in. As many as 120,000 people are now thought to have had their hearing restored by these revolutionary devices, which turn sound waves into electrical signals that stimulate the auditory nerves in the ear via an implanted electrode, and are perceived as sound. But several new developments promise big improvements to the technology in the coming years, so existing users could face tough choices as they have to decide whether to undergo surgery to reap the benefits.  Full Story

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Infrared Light May Improve Cochlear Implants

November 2008

Infrared light can stimulate neurons in the inner ear as precisely as sound waves, a discovery that could lead to better cochlear implants for deaf people. A healthy inner ear uses hair cells that respond to sound to stimulate neurons that send signals to the brain. But hair cells can be destroyed by disease or injury, or can contain defects at birth, leading to deafness. In such cases, cochlear implants can directly stimulate neurons. The hearing provided by today's implants is good enough to enable deaf children to develop speech skills that are remarkably similar to hearing children's. Implant users still find it tough to appreciate music, communicate in a noisy environment and understand tonal languages like Mandarin, however. That's because the implants use only 20 or so electrodes, a small number compared to the 3000-odd hair cells in a healthy ear. More sources of stimulation should make hearing clearer but more electrodes cannot be packed in because tissue conducts electricity, so signals from different electrodes would interfere. In contrast, laser light targets nerves more precisely and doesn't spread, which could allow an implant to transmit more information to the neurons.  Full Story

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NFMI Technology Promises Wireless CIs

November 2009

The most interesting of the products that they demoed was a cochlear implant where the left and right ears implants could communicate with each other using very short range wireless technology. Cochlear implants are put inside deaf people's skulls to interface directly to nerves. Gradually the deaf person (usually a child) can start to hear as the brain works out what to do with those weird electrical signals that suddenly started to appear. I have a friend whose daughter was born deaf and has a cochlear implant and the transformation is nothing short of incredible. But putting two implants, one for each ear, and having them be able to communicate with each other, makes for even better comprehension. With an inductive interface too, it is possible to use a small box that takes Bluetooth and communicates inductively with the implants, allowing deaf people to use the phone or listen to music much more easily (it's too power hungry just to put a bluetooth receiver in the implant).  Full Story

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Comparison of Bimodal and Bilateral Cochlear Implant Users

September 2010

Objectives: Despite excellent performance in speech recognition in quiet, most cochlear implant users have great difficulty with speech recognition in noise, music perception, identifying tone of voice, and discriminating different talkers. This may be partly due to the pitch coding in cochlear implant speech processing. Most current speech processing strategies use only the envelope information; the temporal fine structure is discarded. One way to improve electric pitch perception is to use residual acoustic hearing via a hearing aid on the nonimplanted ear (bimodal hearing). This study aimed to test the hypothesis that bimodal users would perform better than bilateral cochlear implant users on tasks requiring good pitch perception.    Full Story

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Single cochlear implant helps you hear in BOTH ears

February 2011

Marnie McCarthy used to think her three teenage sons were pleasantly quiet. But then she heard them properly for the first time and realised just how noisy they really are. Until six months ago, Marnie had never heard the voices of her boys, aged 17, 14 and 12. Nor had she heard the sound of birdsong, laughter or a ringing telephone. That's because Marnie, now 45, was born almost totally deaf.  She wore hearing aids, but her hearing loss had been becoming increasingly worse over the years. Even with the aids, she could hear only the very loudest sounds.  Hearing in two ears allows people to hear speech better and means a patient can hear where a sound is coming from. And because the devices amplify all noise, it was almost impossible for her to pick out voices, even when she was in a quiet environment. Yet she is now able to hear her sons' voices, along with a host of other `new' sounds, thanks to a recent technological breakthrough - a  single cochlear implant that helps you hear in both ears.   Full Story

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Evaluation of noise reduction technologies in a contemporary cochlear implant system

May 2011

Despite these advances, many cochlear implant users continue to experience substantial difficulty with speech recognition in noisy environments. In particular, recent studies have shown that speech understanding decreases by 30 to 60 percentage points when performance in quiet is compared with performance at commonly-encountered signal-to-noise ratios ranging from +4 and +10 dB.8-11 As a result, cochlear implant manufacturers invest considerable resources into the development of technologies designed to improve speech perception in noise. For example, the newly-introduced Cochlear Nucleus 5 cochlear implant system possesses several features that are intended to improve speech understanding in noisy environments  Full Story

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What's on the horizon for cochlear implants?

December 2011