Hearing loss and dementia may seem like two very different conditions. But research increasingly supports the idea that unaddressed hearing loss requires extra attention from resources in the brain.
Most recently, this idea was addressed in a study published in an August 2020 issue of Neuron. According to the research team from Newcastle University, hearing loss could be associated with one-tenth of the 47 million dementia cases in the world.
“Hearing loss could be associated with one-tenth of the 47 million dementia cases in the world.”
During their research, the team studied three components. Brain shrinkage related to a lack of sound is one of them. They studied underlying causes for both dementia and hearing loss. The team also looked into how resources in the brain have to accommodate for and adjust to hearing loss. This leaves those resources unable to assist elsewhere.
Researchers found that part of the temporal lobe — which is associated with long-term memory — is also connected to “short-term storage and manipulation of auditory information.” The team noted that a person with hearing loss might have changes in brain activity. This results in increased levels of proteins known to be connected to Alzheimer’s disease — thus forging the connection between the two.
“The challenge has been to explain how a disorder of the ear can lead to a degenerative problem in the brain,” Professor Tim Griffiths, from Newcastle University’s Faculty of Medical Sciences, said in the press release. “We suggest a new theory based on how we use the memory system in the brain when we have difficulty listening in real-world environments.”
Past studies have also examined the link between hearing loss and dementia.
In 2018, researchers from Harvard University studied various factors related to hearing loss and dementia. They included memory, brain processing speed, shape, distance, and size recognition. They concluded that there was a link between dementia and older adults experiencing hearing loss. But they did not dive more deeply as to the exact reasoning.
Read more: Are hearing loss and dementia linked?
By acknowledging this link and taking action to address hearing loss, researchers noted that the findings could change the outcome for some older adults. These are adults who would otherwise fall victim to the link between hearing loss and dementia.
In a report about dementia prevention, The Lancet Commission laid out 12 factors that can affect the development of dementia. The leading cause was unaddressed hearing loss. In the report, they noted that the use of hearing aids can offset dementia development.
AT Today, covered the Lancet Commission’s recommendations. “If an individual can hear in a way that is almost natural through hearing aids, the brain will not compensate by relying more on information from other senses,” AT Today wrote. “Primarily, with hearing loss, an individual’s natural reaction to attempt to lip read kicks in. [This] refocuses brain resources and eventually changes the way the brain behaves.”
In addition to hearing aids, cochlear implants are also an option for some individuals. They and can aid in the prevention of dementia.
“While it is difficult, if not impossible, to remediate cortical degradation, hearing loss is widely treatable with hearing aids or cochlear implants,” researchers wrote in the 2020 study. “Thus, an understanding of the mechanisms linking the two could have wide-ranging public health importance.”
Hearing loss can occur as a person ages or due to other circumstantial factors. According to the Mayo Clinic, common signs of hearing loss include:
If you are worried about your own hearing and want to take action, be sure to schedule an appointment with a professional to have your hearing assessed. There are also various online hearing tests. Note these are not as accurate as having your hearing screened by a medical professional.