Compensating for Hearing Loss

By Jane Farrell

Scientists know that as people age, they compensate for hearing loss by tapping into other areas of the brain. But now, it’s becoming clearer how – and where – this compensation takes place.

The findings were published in the journal Nature Communications.

The background: As people age, their peripheral and central auditory system (areas of the brain that help to intake and interpret sound) decline in function and plugging into other parts of the brain is needed to compensate, explains Dr. Claude Alain, senior investigator of the study and Assistant Director of the Rotman Research Institute at Baycrest Health Sciences, in Toronto.

“Prior research found that there’s a change in the brain and how it acts when older adults listen to speech and noise, but people didn’t know the nature of this change,” says Alain. “Our study was able to show that we appear to tap into the speech motor areas, regions of the brain that are important for speech articulation and production, and use that information to identify speech embedded in noise.”

The study analyzed the brain activity of 16 young and 16 older adults and their ability to identify syllables, while the level of noise changed in the background.

This finding is important because it paves the way for programs to be designed to assist seniors with hearing loss and to adapt the way hearing aids are developed. Significant hearing loss is one of the most common chronic health conditions in older adults that affects 90 per cent of seniors who are 80 years and older. A loss of hearing greatly affects an older adult’s ability to socialize and their quality of life.

“If you have impaired hearing, you try to correct that with a hearing aid or assistive listening devices, but it can be difficult to tweak the mechanical aspect to zoom in on a person’s voice,” says Alain. “By showing there are other brain areas that affect hearing you can design training programs that target these brain areas to see if we can improve their use.”