New research shows that problems hearing in noisy settings can trigger changes in the brain linked to dementia
A small but vital part of the brain – the insula – may hold the key to understanding why people who struggle to follow speech in noisy settings are at greater risk of cognitive decline.
A new study suggests this difficulty isn’t just frustrating in the moment but could also signal long-term changes in how the brain works.
Study Insights: MRI Scans and Speech-in-Noise Tests
Researchers at the University at Buffalo found that the left insula rewires itself in individuals who find it hard to process speech against background noise. The study, published in Brain and Language, a scientific journal, strengthens the growing link between hearing loss and dementia, and points to ways interventions could help protect brain health.
The team tested 40 adults aged 20 to 80, combining speech-in-noise hearing tests with MRI scans. They found the left insula showed significantly increased connectivity with auditory regions of the brain in participants who had trouble with background noise. “Your brain is always doing something,” said lead author David Wack, associate professor of radiology at Jacobs School of Medicine and Biomedical Sciences. “When you have hearing loss, you are recruiting other areas of the brain to do more processing in order to decode what’s going on.”
Cognitive Costs and Compensation Mechanisms
This heightened insula activity appears to be a coping mechanism, but one that might come at a cost. The insula plays a central role in cognitive function, and its increased load may reflect an early step toward cognitive decline. “It’s not that hearing loss causes dementia,” said Wack, “but if we could preserve the fidelity of the signal coming in, the brain wouldn’t have to compensate.”
Adaptability and Emerging Interventions
The study also revealed the potential for adaptability. One participant, despite testing poorly on pure tone hearing, performed unusually well in speech-in-noise tasks, possibly due to years of working in a challenging acoustic environment. This offers hope that training or rehabilitation could improve outcomes for others.
Other research supports the importance of protecting hearing to maintain cognitive health. Brain imaging studies show early sensory loss can reshape connections well beyond the auditory cortex, influencing attention, memory, and processing speed. Emerging technologies, including deep learning-based hearing aid models, aim to preserve and enhance the quality of auditory input and may one day lessen this cognitive burden.
The findings add to a growing consensus that hearing care must be treated as a vital part of overall health.
“Regular ear health and hearing checks aren’t just about detecting hearing loss,” said Eva Opitz, a specialist at Hearology®, which offers diagnostic testing and microsuction earwax removal in both clinic and occupational health settings. “They are about preserving your active life for as long as possible. The number of studies that demonstrate how hearing issues are integrally linked to brain health has become overwhelming and impossible to ignore.”
References
- Brain networks rewire to compensate for difficulty hearing speech in noisy environments, study finds – University at Buffalo study on brain connectivity and speech-in-noise difficulty
- Dynamic Processing Neural Network Architecture For Hearing Loss Compensation – Deep learning model designed to improve speech intelligibility for the hearing impaired
- Hearing-Loss Compensation Using Deep Neural Networks – Study on using deep neural networks to emulate auditory nerve function and compensate for hearing loss
- Early deafness leads to re-shaping of global functional connectivity beyond the auditory cortex – Research into brain plasticity in deaf individuals and cross-modal adaptation
- NIDCD Hearing Aids – National Institute on Deafness and Other Communication Disorders overview of hearing aids and their role in cognitive health
- Alzheimer's Disease Facts and Figures – Alzheimer’s Association facts and figures on modifiable dementia risk factors, including hearing loss
