Audiologist Doing A Hearing Test

A Link Between Hearing Loss & Dementia

Two conditions are on the rise and quite common among seniors: hearing loss and dementia. Did you know that they might be linked to one another? 

Among the more than 48 million Americans living with hearing loss, a full two thirds of people over age 70 have some form of hearing loss. Rates of dementia are increasing, and Dr. Frank Lin, one expert on the relationship between hearing loss and cognition, predicts that the numbers of people with dementia will double every twenty years. 

Two such common conditions make us wonder how they could possibly be connected. Many researchers are trying to tackle this question, digging into the ways that the two are related. Yet, the bare facts report that those with hearing loss are much more likely to develop dementia than their demographic counterparts who do not have hearing loss. 

Let’s take a look at the theories about how hearing loss and dementia might be connected, as well as how treatment such as hearing aids might be able to step in and reduce that risk. 

The Four Possible Connections

Although we know that hearing loss and dementia are statistically correlated, researchers have not yet reached consensus about the ways in which they relate. A few specialists point to the role of blood circulation in both hearing and brain health. It is hypothetically possible that high blood pressure might be preventing oxygen from getting to both the inner ear and the brain, making both of them experience problems, in effect, due to a third cause. Although some specialists float this possibility, most are skeptical, noting that the presence of a third factor in high blood pressure would have been picked up in health data analysis. 

The second major theory has to do with the loss of brain mass that happens when a person has sustained hearing loss. When a person is unable to process sound through hearing, the auditory cortex that is devoted to this task can actually shrink in size. This shrinking size of the auditory cortex requires other parts of the brain to pick up the slack. If there is a hearing task presented to the brain, other regions, including those devoted to complex thought, can be repurposed for the task of listening. As you might imagine, this repurposing of gray matter that was meant for cognition means that it is put under undue strain. Perhaps this strain and reallocation of activities has a link with the onset of dementia. 

The third possibility when it comes to hearing loss and dementia looks at the relationship between spoken conversation and cognition. Consider a person who does not have hearing loss. The ears capture units of sound and transmit them to the brain. 

Once they are available for cognition, these units are assembled, along with other visual and sensory information, into meaningful thoughts. Language is built on syllables, phonemes, and tiny units of speech, and the brain is responsible for interpreting them. A person with hearing loss, on the other hand, does not have all the necessary units to make sense of fragmented hearing. 

Without all the puzzle pieces, the jigsaw puzzle becomes complicated and taxing to complete, and errors are inevitable. This process overloads cognitive functioning, and researchers wonder if the additional stress on language-based thought might be related to dementia.

A final potential explanation for the relation between hearing loss and dementia has to do with social isolation. In this case, a chain reaction would indirectly link hearing loss to social isolation which then in turn would lead to dementia. We know that social isolation is linked to both conditions, and one can imagine a situation in which hearing loss would lead a person to feel frustrated with person-to-person interactions. These interactions are crucial to maintaining the sharpness of thought, and without getting enough human conversation, the brain might be more prone to developing dementia. 

Seeking Treatment for Hearing Loss

As researchers and specialists continue to pursue answers when it comes to the link between hearing loss and dementia, the fact remains that they have a relationship. With this in mind, it is more important than ever to get a hearing test and to seek treatment. Our team is here to help. Contact us today to schedule an appointment for a consultation.