Hearing aids have come a long way over the centuries, from giant funnel-like ear trumpets to lilliputian devices that hide inside an ear. Today computer technology is creating not only smaller but smarter aids, able to adapt to different noise environments in a way that would have seemed like science fiction just a couple decades ago.
“Digital aids have changed the world of hearing,” says Cathy Peterson, general manager at Hamilton’s Provincial Hearing Consultants clinic. “It’s absolutely amazing technology and wasn’t even available five years ago.”
Peterson, who started using hearing aids about 10 years ago, is well positioned to see the differences from her first models, which amplified all sounds. The digital aids she now wears contain a variety of computer programs that she can change with the push of a button on her watch – “I tell people I’m like James Bond, I can change my hearing with my watch!” she jokes.
One program allows her to tune out background noise, such as when she’s in a restaurant, and just hear what is coming from in front of her, making conversation easier. Another lets her tune into sounds from her right or left side, handy when driving and she wants to hear her passenger and not the road noise.
She even has one for music. “I don’t want to cut off any of the sound when I’m listening to music. I want to hear it as it’s played, so I have a setting that’s just for that.”
While remote controls, like the one on Peterson’s watch, allow the user to flip from one program setting to another, she says today’s hearing aids are so sophisticated they often don’t need to be adjusted manually but are able to read the environment and change automatically to adapt to the noise levels.
There have been “tremendous advancements,” agrees Snookie Lomow, executive director with the Canadian Hard of Hearing Association. So much so that the public has been challenged in keeping pace with the improvements. “We hold an annual educational conference every year to educate the public to the latest devices and hearing aids.”
Another major improvement, Lomow says, is the miniaturization of the aids, small enough to fit into the inner ear.
Peterson’s aids are worn on the outside of the ear with small clear tubes that go into the canal but she says they’re also so small that they’re “virtually invisible. If I don’t mention it, most people won’t know that I wear them.”
But despite all these advances, less than a quarter of the population who could benefit from hearing aids are actually using them, says Gora Ganguli, president and CEO of Vita Sound, an company based in Concord, Ont. that’s poised to launch a next generation version that he hopes will change that.
The NeuroCompensator aid, slated for launch into the marketplace June 1, uses technology developed in Canada that simulates the working of a normal healthy ear to analyze the complex patterns of an individual’s hearing loss and tailor a program to compensate at the auditory nerve level to restore a more normal pattern of electrical impulses going to the brain.
“It’s a completely different way of designing hearing aids,” says Sue Becker, a professor in the department of psychology neuroscience and behaviour at McMaster University, who conceived the idea a decade ago and has spearheaded the research and development of the technology.
What happens now, she says, is an audiologist maps hearing levels by playing different sounds and determining how much amplification is needed for each tone and frequency. But complex sounds contain more than one pure tone or frequency. “Our model,” she explains, “is able to take into account those interactions across frequencies and decide how much to amplify at each moment, based on the combinations of frequencies coming in and how to best restore a very natural percept of that sound.”
Ganguli suggests visualizing the auditory nerve, made of hundreds of little hair cells that take vibrations from the eardrum and translate them into electrical signals for the brain, as a forest full of trees. In a healthy ear, all the trees are good but in an impaired ear, there are areas of dead trees, in effect “holes in your hearing.” The NeuroCompensator deduces where those holes, or dead zones in the forest, are and offloads the signals to other trees, forging new pathways to the brain.
The science behind it is complicated but one of its big advantages, say Becker and Ganguli, is that once the computer program has been developed it can run the test results from an audiologist and kick out an individualized solution that goes into the aid, reducing the need for  lots of complex programs. Simple hearing aids can be purchased for well under $1,000 but the addition of multiple programs that occasionally need enhancement can push up the price into thousands of dollars, Ganguli points out.
The price point for the NeuroCompensator aids will range from $500 to $1200 per ear, says Ganguli. Most provinces have some form of subsidy. In Ontario the Assistive Devices Program pays 75 per cent up to $500 for each hearing aid every three years.