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In 2013, Johns Hopkins University researcher and epidemiologist Dr. Frank Lin led a study that was the first to measure the possible consequence of hearing loss on mental performance.

Research volunteers with hearing loss took repeated cognitive assessments, used to measure memory and thinking skills, over the course of six years. Hearing tests were also performed over the same time frame.

What the researchers discovered was concerning: the cognitive abilities of those with hearing loss decreased 30 to 40 percent faster than those with normal hearing, even after accounting for other contributing factors like high blood pressure, age, and diabetes.

But that wasn’t all. Not only did those with hearing loss experience higher rates of cognitive decline—the decline was directly linked to the severity of the hearing loss. The more serious the hearing loss, the greater impairment to brain function. In addition, those with hearing loss displayed signals of significant cognitive deterioration 3.2 years earlier than those with average hearing.

The research reveals a strong association between hearing loss and cognitive decline, but the question persists as to how hearing loss can cause cognitive decline.

How Hearing Loss Triggers Cognitive Decline

Researchers have suggested three explanations for the connection between hearing loss and cognitive decline:

  1. Hearing loss can contribute to social isolation, which is a recognized risk factor for cognitive decline.
  2. Hearing loss forces the brain to dedicate too many resources to the processing of sound, at the expense of memory and thinking.
  3. A common underlying trauma to the brain causes both hearing loss and diminished brain function.

Possibly it’s a combination of all three. What is clear is that, regardless of the cause, the relationship between hearing loss and cognitive decline is powerful.

The concern now becomes, what can we do about it? Researchers estimate that 27 million Americans over age 50, including two-thirds of men and women aged 70 years and older, suffer from some kind of hearing loss. Is there a way those with hearing loss can avoid or reverse cognitive decline?

Can Hearing Aids Help?

Remember the three ways that hearing loss is believed to trigger more rapid cognitive decline. Now, consider how hearing aids could resolve or correct those causes:

  1. People that use hearing aids boost their social confidence, become more socially active, and the side effects of social isolation—and its contribution to cognitive decline—are mitigated or eliminated.
  2. Hearing aids protect against the overtaxing impact of struggling to hear. Mental resources are freed up and available for memory and reasoning.
  3. Hearing aids present heightened sound stimulation to the brain, helping to re-establish neural connections.

Admittedly, this is only theoretical, and the big question is: does using hearing aids, in fact, slow or protect against accelerated mental decline, and can we measure this?

The answer may be discovered in an forthcoming study by Dr. Frank Lin, the head researcher of the initial study. Lin is presently working on the first clinical trial to study whether hearing aids can be objectively measured to prevent or alleviate brain decline.

Stay tuned for the results of this study, which we’ll cover on our blog once published.