Hearing Loss & Brain Health

Although, the ears are responsible for perceiving sound but understanding what we hear is a brain process. The ears deliver sound to the brain where meaning is applied through use of cognitive functions like, listening, understanding and memory. It is necessary that both organs work properly together for hearing to occur.

We  all want to retain our mental sharpness as we get older. Hearing loss  plays a role in our ability to stay mentally sharp as we age. In recent years, a considerable amount of scientific evidence has been published highlighting the association between untreated hearing loss and cognitive decline and dementia. Recent literature indicates that individuals with hearing loss have a 55% greater risk of developing dementia as compared to those with normal hearing, and it increases linearly with the severity of hearing loss. Research findings published in The Lancet in 2017 stated that one in three cases of dementia could be prevented if people managed a number of lifestyle factors in midlife (between ages 40 to 65) including hearing loss.   

The association between hearing loss and cognition is not fully understood. Overall, there are some theories that might contribute to the association between hearing loss and cognition. One theory is that hearing loss leads to a decreased input to the brain, so there is less processing that occurs, which contributes to cognitive decline. Another theory is that early cognitive deficits may impact a person’s ability to process sound, and thus contribute to hearing loss.

Regardless of which theory is right, it is apparent that there is an association between hearing and cognition. This association highlights the need to improve our approach to testing and treating hearing loss. Particularly after the age of 50, hearing tests should be as routine a part of healthcare as sight tests and dental checks.

Like our vision, our hearing is constantly changing however, for many, the impact of hearing loss on the brain is often overlooked. If you have a hearing loss, access to sounds is compromised and brain stimulation is reduced. Making sense of sound requires more mental energy and cognitive resources. This often leads to withdrawal from social interaction and an increased risk of mental decline. 

Why untreated hearing loss is bad for your brain

Very often, people aren’t aware of hearing loss, as it happens slowly over a matter of years. Even after diagnosis, people wait an average of 10 years to actually get the hearing aids that’ll help them hear better. That is a mistake that should be avoided, since failing to treat hearing loss can result in auditory deprivation and over time, the parts of the brain responsible for hearing can shrink or atrophy from lack of use. 

What is auditory deprivation?

Auditory deprivation is when the brain has difficulty understanding and processing information due to the lack of auditory stimulation. As a result of untreated hearing loss, the brain loses the ability to process sound and over time, those parts of brain which are normally responsible for hearing get "reassigned" to other tasks, resulting in brain atrophy. It can affect anyone with hearing loss, not just severe cases. These negative changes in the brain may improve with consistent hearing aid use. Brain shrinkage may slow or stop, and the brain my begin to pick up on sound signals once more.

The best way to prevent auditory deprivation from occurring is to be proactive when it comes to your hearing. Even mild hearing loss can affect understanding and processing and is linked to a decline in cognition and moderate to severe is linked to dementia.  It is recommended that everyone over age 50 get a hearing screening or a diagnosis evaluation, whether they have hearing issues or not.