Age-related hearing loss, known as presbycusis, affects millions of older adults and often makes it difficult to understand speech, especially in noisy environments.
Scientists have long observed that people with hearing loss are more likely to experience cognitive decline, including problems with memory and thinking.
However, the biological link between the two has remained unclear. A new study offers fresh clues about how changes in the brain may connect hearing loss and declining mental abilities.
Researchers from Tiangong University and Shandong Provincial Hospital studied brain activity and structure in people with presbycusis to understand what might be happening.
Their findings, published in the journal eNeuro, point to changes in how different parts of the brain communicate with each other.
The team identified a measure called the functional-structural ratio, or FSR, which reflects the balance between how the brain is built and how it functions.
In people with age-related hearing loss, this balance appears to be disrupted. Certain brain regions involved in processing sound and speech showed weaker connections to broader brain networks. These included areas that help interpret voices and recognize spoken language.
At the same time, regions involved in memory, attention, and decision-making also showed reduced connectivity.
People with weaker connections in these areas tended to have more severe hearing loss and performed worse on tests of memory and executive function, which includes skills such as planning and problem-solving.
The researchers believe these findings suggest that hearing loss is not only an ear problem but also a brain issue. Reduced hearing may lead to changes in brain activity over time, which could contribute to cognitive decline.
Alternatively, both hearing and cognitive problems may stem from shared age-related changes in the brain.
Importantly, the study highlights the possibility that protecting hearing could help protect brain health. If hearing loss is linked to structural and functional changes in the brain, treating it early—through hearing aids, medical care, or preventive measures—might slow or reduce cognitive decline.
Scientists also suggest that the functional-structural ratio could eventually become a useful tool for doctors. By examining brain scans, healthcare providers might be able to identify people at higher risk of dementia before symptoms become severe, allowing earlier intervention.
While more research is needed, the study reinforces the importance of paying attention to hearing health as people age. What may seem like a minor inconvenience could be connected to broader changes in brain function. Maintaining hearing ability may not only improve communication and quality of life but also help preserve memory and thinking skills in later years.
