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One small insect impact on hearing aids

How one small insect made a big impact on hearing aids

Published 16-07-2019
Last Updated 18-07-2019

The directional microphone has been a major improvement in hearing aid technology. Most would have no idea that its developers got the idea after researching the way a tiny, yellow insect takes in sounds.
Modern hearing aid technology can learn a thing or two from this small fly. That's because the Ormia Ochracea, a small yellow nocturnal fly that hunts crickets at night has a valuable sensitive auditory system; a system certainly worth studying. 

This fly does not have hearing loss. In fact, it has one of the most keenly defined senses of hearing in the animal kingdom. By simple comparison the Ormia Ochracea's hearing is even better than an owl's hearing - on par to the clear 20/20 vision of a hawk. 

“Their sense of hearing is remarkable considering their ears are so close together – this trait would make directional hearing impossible in any other animal,” says zoology professor Andrew Mason of the U of T at Scarborough. The fly's hearing is as good as an owl's vision is good. In fact, Their hearing is so sensitive that researchers throughout hearing aid testing clinics throughout the country have covered its contribution to science in academic journals such as the Acoustical Society of America, Science, and Applied Physics Letters

What They Learned

Attached to their front legs is a small coupling connecting for both of its ears. The coupling acts like a seesaw, tilting in the direction the sound is traveling. This gives the fly a heightened awareness of the direction and distance that the sound is coming from. A fully grown adult fly is able to use their hearing to identify minute changes in incoming sounds, and adapt accordingly.

Interestingly, the fly struggles the same way that hearing impaired people do in a loud cocktail party or loud restaurant. Making sense of echoes and background noise interference is a huge challenge. 

Flies can tell whether sounds come from in front or behind, but they struggle to detect sounds from below or above, such as echoes in a large room. The scientists hope that once developed further, the technology could be used in creating low-power hearing aids that can better discern conversations from background noise, along with possible military applications.