Essex, United Kingdom — Crash dummies help auto makers make stronger and safer cars. Now researchers from the University of Essex and Phonak are creating new software hearing dummies that can help with diagnosis, as well as to create more precise and customizable hearing aids.
The research is being carried out by a team in the University’s Department of Psychology with funding from the University’s Engineering and Physical Sciences Research Council (EPSRC).
The goal of the research is to enable hearing aids to be carefully calibrated so that they address the particular underlying hearing condition affecting each individual patient. The hearing dummies may also help to reduce sound interference, which leads to an inability to follow conversations in noisy environments.
People also differ in how much they are affected by noisy environments, which is why developing a tailor-made approach represents such a significant breakthrough.
The first key advance has been the development of unique computer models (or "hearing dummies") that can use the information collected during the tests to simulate the precise details of an individual patient’s hearing.
By altering individual mathematical algorithms within the computer models, the dummy’s hearing capabilities can be adjusted until they perfectly match the hearing characteristics of the patient. This will then indicate the likely cause of the patient’s hearing impairment.
Lead researcher Professor Ray Meddis uses tailor dummies as an analogy for his research. He says, “In the same way that a tailor’s dummy is used to measure and fit a garment for a particular person, our software dummy is used to gauge a patient’s hearing requirements so that their hearing aid can then be programmed to suit their needs right at the beginning of the process without the need to come back for further time-consuming adjustments to their device.”
The second key advance achieved by Professor Meddis and his team has been in the design of new hearing tests. Current clinical practice focuses on "threshold testing" to identify how quiet a sound can be while remaining audible, and hearing aids are generally prescribed solely on the basis of these tests.
The new tests, which are quicker and easier to use, concentrate on higher sound levels more typical of everyday life.
“Our work has shown that, when it comes to hearing impairment, no two people are alike,” says Meddis. “That’s why two people with apparently similar hearing thresholds often react very differently to their hearing aids.”
The third advance involves developing a new kind of hearing aid that simulates how a normal ear works. The aim of this new aid is to restore the particular aspects of hearing that are faulty and to do this as naturally as possible.
In collaboration with hearing aid manufacturer Phonak, Professor Meddis and his team have now designed a lab-scale version of a device that is being tested on patients. The next step is to work with a manufacturer to fine-tune the software and miniaturize the technology.
“Traditionally, the fitting of hearing aids has focused on symptoms, not causes,” Professor Meddis comments. “Our aim has been to break through the limitations of current hearing aids and current hearing assessment procedures, and so ultimately enable hearing impaired people to play a much fuller role in society.”
More information is available in an audio slide video:
SOURCE: University of Essex