Optimising the value of Prof Tania Hanekom Prof Johan J Hanekom Source: South African Institute of Electrical Engineers, May 2020, wattnow.
cochlear implants through
computational modelling For the past two decades, researchers from the Bioengineering Research Group in the University of Pretoria’s Department of Electrical, Electronic and Computer Engineering have been working on the development of three-dimensional (3D) user-specific computational models of cochlear implants to personalise these devices so as to optimise their value for a particular user.
A COCHLEAR IMPLANT AS A NEURO-PROSTHETIC DEVICE A cochlear implant is an electronic device that is surgically placed under the skin behind the ear. It provides a sense of sound to someone who is profoundly deaf or severely hard of hearing by bypassing the damaged cochlea and sending sounds electrically to the brain. A cochlear implant can give a deaf person useful hearing of environmental sounds and help them understand speech, and communicate orally. This is arguably the most successful neuro-prosthetic device to date. It aims to cure deafness in an individual suffering from sensorineural hearing loss. It replaces the entire auditory system from the external ear up to the point that the inner hair cells (the specialised transducer cells that are responsible for conveying the incoming sound to the auditory nervous system) connect to the peripheral auditory neurons. An electrical connection to the peripheral auditory neurons of a hearing-impaired person is
established through a miniature electrode array that is implanted into the inner ear (cochlea). Current injection through the electrode array is driven through one or more current sources that are controlled by an external unit. The external unit, which is worn behind the ear, contains a microphone to capture incoming sounds and a speech processor that encodes these sounds as a stimulation protocol to target appropriate neural populations. A telemetric link between the internal and external parts of the device is used to transfer data and power. By the end of 2015, the largest implant manufacturer had sold more than 400 000 devices since its first-generation devices became commercially available in 1981. In 2016, around 600 000 global implants had been supplied across all manufacturers, with approximately 45 000 added to this number annually. 2 0 2 0
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A COCHLEAR IMPLANT CAN GIVE A DEAF PERSON USEFUL HEARING OF ENVIRONMENTAL SOUNDS AND HELP THEM UNDERSTAND SPEECH, AND COMMUNICATE ORALLY. THIS IS ARGUABLY THE MOST SUCCESSFUL NEURO-PROSTHETIC DEVICE TO DATE, WHICH AIMS TO CURE DEAFNESS IN AN INDIVIDUAL SUFFERING FROM SENSORINEURAL HEARING LOSS.
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