Hearing Loss & Dementia

When we think about hearing loss, we tend to think about our ears. The reality, though, is that hearing happens in our brains. Indeed, our ears play a huge role in the auditory process, but the bulk of sound recognition and auditory processing happens in our brains. When we experience hearing loss, our brains struggle to make sense of sounds and speech. As a result, people with untreated hearing loss have been found to be at greater risk for dementia.


Your Auditory System

You just heard the sound of a door slamming. Let’s rewind: your brain just recognized the sound as a door slamming. Let’s rewind even further: first, sound waves enter your outer ear then travel through your ear canal, where it is amplified in the middle ear and sent to the inner ear. In the inner ear, the vibrations from these sound waves are translated by your inner ear hair cells into neural signals. From here, the neural signals travel well-worn pathways to the auditory center in your brain to be processed as sound. Here, in your brain, this sound is recognized as “a door slamming.”

When a person experiences hearing loss, one or more steps in this process malfunction, which leads to the brain’s inability to register sound.

Our sense of hearing is one of the channels by which our brains take in information and allow us to interact with and respond to the world around us. Familiar sounds, such as songs that get stuck in our heads or the recognition of someone’s voice, are familiar because our brains remember them from multiple exposures. Hearing loss interferes with this intricate process, and if left untreated, over time hearing loss could lead to a higher risk for dementia.

Studies Linking Untreated Hearing Loss and Dementia

In recent years, researchers have found potential links between untreated hearing loss and dementia. Frank Lin, an otologist at Johns Hopkins University, heads up a number of these studies. “The general perception is that hearing loss is a relatively inconsequential part of aging,” says Lin. However, studies conducted by Lin and his team have revealed previously unforeseen consequences of untreated hearing loss, including potential links to an increased risk for dementia.
In one study, Lin and his fellow researchers tracked the cognitive abilities for 2,000 older adults (with the average age of 77) over six years.

In one study, Lin and his fellow researchers tracked the cognitive abilities for 2,000 older adults (with the average age of 77) over six years. Results show that
of test subjects were more likely to have diminished cognitive decline, compared to subjects with normal hearing. As we age, our brain tissue mass naturally decreases, but with untreated hearing loss, there is added strain to our brains in the form of a heavier cognitive load.

This idea of a “heavier cognitive load” was explored in another study conducted by Lin and his team at Johns Hopkins. They found that of 639 test subjects, those with untreated hearing loss were more likely to develop dementia over the course of 12-18 years.

Untreated Hearing Loss, Dementia, and the Bigger Picture

the Hearing Loss Association of America, individuals who experience hearing loss report that the biggest challenge is making sense of verbal communication, especially in louder social settings.

As a result, people who were once active and engaged may be less likely to participate in cultural events, hobbies, and social meetings than before. Unfortunately, this has unforeseen effects: studies have found that people who are more social are less likely to develop dementia, due to consistent engagement with the world around them. These stimulations keep our brains active. As such, we can see the interconnectedness of untreated hearing loss, anxiety, social isolation: all of which are considered triggers for dementia.

According to Dr. Lin, it is important to note: “I have a 92-year-old grandmother who’s had a moderately severe hearing loss for many years now. She’s sharp as a tack. I was talking to her about my research and she looks at me and says, ‘Are you telling me I’m definitely going to get dementia?’ I said, ‘Not by any means.’” In other words, he clarifies that “simply being at increased risk does not mean a person is certain to develop dementia.”
What can we do to mitigate this risk?

Get Your Hearing Tested Annually

Currently, one-third of Americans age 65 or older experience some degree of hearing loss; 50% of people over the age of 75 experience hearing loss. With this in mind, hearing specialists recommend that people being annual hearing tests at the age of 50.

If a hearing loss is detected, we will provide you with a series of treatment options. The most common treatment for hearing loss is the use of hearing aids.

In a 2011 Japanese study, subjects with varying levels of hearing were given auditory and cognitive examinations over the course of three years. Researchers found that subjects who experienced hearing loss and were prescribed hearing aids early on scored higher on tests of their cognitive abilities, compared to subjects who left their hearing loss untreated.

While links between hearing loss and dementia continued to be studied, with no definitive claims, it is clear that treating hearing loss brings significant benefits to your life, from improving sound signals, assisting with speech recognition, improving your cognitive abilities, and allowing you to stay connected and active with your loved ones and your community. These elements could go a long way in helping you mitigate the risk for developing dementia.