Researchers in Scotland have drawn inspiration from the insect world in a bid to revolutionise the world of miniature hearing aid design. The University of Strathclyde, and the MRC/CSO Institute for Hearing Research (IHR) at Glasgow Royal Infirmary are to trial a miniature directional microphone that replicates the directional attributes of many insects.
The design of microphones has remained largely underdeveloped in recent years, despite considerable advances in acoustic science and the commercial opportunities offered by the needs of an aging population. However, the Scottish team believe they have found a way to achieve the sort of directional sensitivity that insects enjoy while also meeting the cosmetic requirements that modern users demand. Hearing solution specialists, such as Hidden Hearing, will be amongst those especially interested to see how these trials develop.
The problem with traditional microphones, according to Dr James Windmilll, of the Centre for Ultrasonic Engineering at Strathclyde, is their inability to tell which source of sound is important to a listener. On that basis, a traditional hearing aid will boost background noise to the same degree that it boosts the speech of someone speaking nearby. In that respect, they offer only a partial solution.
The breakthrough the researchers hope to achieve is to develop a device that is able to emphasise the sounds emanating from in front of the listener. A particular problem for users of traditional hearing aids is the way sound bounces around in large rooms, thus bombarding the hearer with wave after wave of distracting noises and making it impossible to distinguish a particular sound source. The researchers are hoping to be able to evaluate the effects that distance plays in the experience of different sounds e.g. a passing aeroplane as compared with a radio or television.
In a further cutting edge twist, the researchers are to experiment with laser printing as a means to construct the hearing aid design. The effects of such designs on the acoustic properties of the microphones, as well as the aesthetic and ergonomic aspects of the devices, will all be assessed.
The design, construction and testing of the new microphones and hearing aid structures will take place at Strathclyde and the actual testing and evaluation of the devices, including human trials, will be conducted by the IHR in Glasgow.
The Scottish scientists are not the only hearing researchers turning to the animal world for inspiration. Scientists at the University of Aarhus, Denmark, believe that their examination of lung fish may give a clue to the evolution of all hearing mechanisms in the animal world. The Danes have found that lungfish, which are closely related to the first four-legged species to colonise the land over 350 million years ago, respond to vibrations in their brains, even though they have no middle ear with which to detect such pressure changes directly. The researchers also found the same to be true of Salamanders.
We have a lot to learn from the natural world when it comes to advancing our own and hopefully from this research we can enjoy new ways of aiding the hard of hearing, so that they can continue enjoying their lives like normal.