When you think of animals with a sharp sense of hearing, what comes to mind? A bat? An owl?
Think again.
Scientists at the University of Texas Austin have been studying the Ormia Ochracea: a yellow fly that might be revolutionizing the way we develop hearing-aid technology.
Let’s take a minute and look at how insects “hear” in the first place.
Most bugs tend to be so tiny that sound registers on both sides of their body simultaneously, rendering them unable to tell what direction those noises are coming from. The Ormia, on the other hand, has a unique miniscule seesaw-like structure that sits in the 2mm-space between its ears, causing the mechanism to vibrate and allowing the fly to hear multi-directionally. For example, the Ormia is the only fly of its kind that can precisely determine the exact location of a cricket based just on its chirps. Pretty cool stuff!
So how does this relate to the human brain?
In our case, the brain is built to determine the source of sounds based on a split-second delay between its being detected by the left and right ears. For those suffering from hearing loss and working with a hearing device, it can be difficult to place exactly where sounds are coming from at any given time. Even the most up-to-date hearing devices only allow a person to ascertain sounds coming from their front or back. This is why multi-directional sound, such as an echo from a large, cavernous space, can be totally disorienting for a person suffering from hearing loss.
Despite real advances in sound analysis for hearing aids, the actual microphone itself has used the same outmoded technology for decades. And current directional microphone technology? It adds unwanted cost, weight, and power requirements that end up compromising the design of the aid itself.
Thankfully, scientists at the University of Texas Austin are turning to the Ormia to create a hearing aid that remedies this pervasive issue. The UT research team built an almost exact replica of the fly’s hearing device, but integrated with piezoelectric materials and allowing mechanical strain to be converted to electrical signals and a flexible beam – through which the team can measure the flexing and rotation.
So how exactly does this improve your hearing aid?
Your hearing aid will self-select the sounds that are closest to you and filter out any unwanted noise. This is HUGE. At a concert hall trying to have a conversation with your friend? You’ll hear only that intimate conversation – without any of the echo. At a busy intersection and attempting to get directions from your passenger? You’ll hear only the voice next to you, without being drowned out by loud honks and sirens.
Cooler still? This project will also investigate 3D printing techniques to optimise the hearing aid design so that it works best acoustically in conjunction with the new microphone. A better, sleeker hearing device that you can print yourself? Well, sign us up!
So next time you think of squashing that little fly on the wall? Well, you might want to give it a thumbs-up instead.