Researchers have known for some time that there is a powerful relationship between hearing ability and cognition. Those who have hearing loss tend to experience cognitive decline in their senior years more often and at a faster rate. They even have higher rates of dementia, including Alzheimer’s disease. These relationships have been established in a variety of different ways and by using different measures. A recent study undergirds these past findings and adds to their precision by using a measure of mild hearing loss. The study finds that, indeed, even those with mild hearing loss are more likely, on average, to have cognitive decline than their counterparts. Let’s look at the study, as well as what it might tell us about the nature of hearing and language.
This new study used two data sets to build a large group of 6,451 survey respondents aged 50 and older. The two data sets include information on two populations: the Hispanic Community Health Study (HCHS) and the National Health and Nutrition Examination Study (NHANES).
The first study only talked with people in the Hispanic-identified community, while the second study was generalized to all people in the US population. These two groups made it possible for researchers to compare people with similar characteristics according to not only race, ethnicity, and national origin, but also gender, age, and other social demographics. For instance, it is most useful to know not simply if the group of people with hearing loss were more likely to experience cognitive decline because some other third factor might be causing both hearing loss and cognitive decline at the same time, most likely age.
However, even within a demographically similar group, such as 55-year old African-American women, those who had hearing loss were more likely to experience cognitive decline than those who did not have hearing loss. The most significant offering of this new study is that even mild hearing loss of not more than 15 decibels is sufficient to correlate with cognitive decline.
What does this study tell us about the relationship between hearing loss and cognitive decline? In the first place, we know that it’s not simply age that causes both conditions at the same time. There’s something unique about hearing loss that is related to cognitive decline, as well. We also know that the relationship is not only linked to moderate, severe, or profound hearing loss, like the experience of those who have trouble communicating at all.
On the contrary, many people with mild hearing loss feel like they don’t need any support with communication. They believe that they are getting along just fine without the support of hearing aids. This finding points to a deeper process at the level of brain activity. Other studies have shown that those with mild hearing loss use different parts of their brains in conversations. Specifically, they recruit parts of the brain that are usually activated for processing complex ideas for the simple process of auditory decoding. When it is difficult to understand what someone says, even in a subtle way, the brain jumps to the task of solving this puzzle.
Many scholars suspect that this reorganizing of brain activity has a relationship with cognitive decline, making it difficult to process the ideas themselves. This process of overloading new parts of the brain with the otherwise simple task of transforming sound into meaningful language might explain why there are higher rates of dementia, including Alzheimer’s disease, as well.
Seeking Treatment for Hearing Loss
If you have a loved one with mild hearing loss, this information can be a call to action. Perhaps your loved one doesn’t think that hearing aids are necessary yet. They might even think that they are communicating just fine, finding ways to use context clues and other sensory information to establish the meaning of what they hear. Although this may seem to be the case, a more profound shift is happening behind the scenes at the level of brain activity. Rather than risking something like cognitive decline, your loved one needs to seek assistance as soon as it becomes necessary. Why not encourage your loved one to make an appointment for a hearing test today?