The hearing aid feature designed for face masks
In July last year US hearing aid company Signia launched a function to help people with hearing loss better understand the speech of people wearing masks. The Face Mask Mode - which they say was the first feature of its kind - works via their smartphone app, increasing the loudness of frequencies associated with speech by 6dB.
Masks can reduce frequencies in the 2000-8000 Hz range by between 3 to 12 dB depending on the type of mask. Along with preventing lip-reading, they pose a serious communication challenge for people with hearing loss, but are vital to protect from coronavirus.
"It took a short amount of time to develop Face Mask Mode for the Signia app" explains Eric Branda PhD. AuD, Signia's Director of Research Audiology. "As soon as mask usage started growing globally, the impact of masks on communication became a hot topic.
"Although we had a general idea of the frequencies affected by mask wearing and by how much, we knew it was important to be precise when creating this new feature. That said, we looked at published data on face masks and determined how Face Mask Mode could be most effective for the majority of wearers and moved quickly to make it available to the public."
As well as boosting specific frequencies, the Face Mask Mode also adjusts noise reduction and microphone settings to the ideal levels for speech.
To activate the function, the user taps an on-screen button on the Signia app. When tapped, it turns from grey to red. After the hearing aid wearer has finished talking to the person wearing a mask, they can deactivate Face Mask Mode by simply tapping the button again, turning back to grey. It also deactivates when the wearer resets the hearing aids and changes program.
Branda says that once the need for this feature was identified, Signia moved quickly to develop the solution in a short space of time. "We’re lucky to have very talented individuals at Signia who could quickly interpret the effects of masks on speech and how to address them.
"Face Mask Mode started as an idea that needed a plan for the feature itself and how it would work, in addition to development and implementation in the app and as it modifies the hearing aids. Next, there was the means of creating scientific and marketing communications for the hearing care professionals and hearing aid wearers. Despite the challenge, our team was able to put in the hours to make it happen."
During the development stage it was important to keep a close relationship between hardware and software design. "Planning is done well in advance to identify what can be added to the hearing aid" Branda says. "It’s a small amount of space to work in, so when you consider rechargeable functionality, wireless technology, the chip doing the processing, components like microphones, and the algorithms that let them interact, every millimeter and milliamp has to be accounted for."
"With the existing wireless communication and connectivity options, there are a number of ways to help hearing aids provide more functionality for the hearing aid wearer. What we need to look at for the future is continuing to provide advanced technology that is easy to use, just like how pressing a single button in the app activates Face Mask Mode to help ease communication."