Are you turning up the volume on the television set or straining to hear conversations? You may be suffering from hearing loss. And that could impact your overall brain health.
An estimated 48 million Americans suffer from hearing deficits. According to recent studies, those who permit hearing problems to go untreated are at greater risk of developing dementia and related cognitive disabilities. On the flip side, treating hearing loss could help prevent the cognitive decline and dementia associated with aging.
The National Institute on Aging defines dementia as, “The loss of cognitive functioning—thinking, remembering, and reasoning—and behavioral abilities to such an extent that it interferes with a person’s daily life and activities. These functions include memory, language skills, visual perception, problem solving, self-management, and the ability to focus and pay attention. Some people with dementia cannot control their emotions, and their personalities may change. Dementia ranges in severity from the mildest stage, when it is just beginning to affect a person’s functioning, to the most severe stage, when the person must depend completely on others for basic activities of living.”
Many studies confirm the link between hearing loss and dementia. For example, one study found that hearing loss actually speeds up the loss of cognitive abilities, such as concentration, memory, and planning skills. In that study, 2,000 adults with an average age of 77 were tracked for six years. Researchers found that those who began the project with a hearing loss serious enough to interfere with conversation were 24 percent more likely than those with normal hearing to experience a decline in their cognitive abilities.
Another study tracked 639 people considered “mentally sharp” for 12 to 18 years. Researchers found that those who developed a hearing loss during that period were more likely to develop dementia. In fact, their risk was triple that of those with normal hearing.
How does hearing loss contribute to cognitive problems and dementia? Experts suggest four possibilities:
- A common “physiological pathway.” For example, a health condition that contributes to both cognitive decline and hearing loss, such as high blood pressure or high cholesterol. Researchers now track these factors in brain health studies, but have yet to find a causal relationship.
- Cognitive load. In essence, factors that place a stress on the brain. A hearing loss, for example, causes an individual to constantly strain to hear, which in turn forces the brain to draw on other functions to compensate. This, in turn, may impact the ability of the brain to encode memory, eventually reducing the brain’s resilience. A hearing aid or cochlear implant makes it easier for a person to hear, so the brain expends less energy to accomplish that task and is free to perform other cognitive tasks.
- Brain structure. Certain parts of the brain shrink when they don’t get enough stimulation. Researchers suggest that hearing loss may affect the structure of the brain in that way. For example, brain imaging studies reveal that older adults with hearing loss actually lose brain cells in the area of the brain that receives and processes sound. The loss of those brain cells has an impact on overall brain health: Fewer brain cells results in a smaller or shrinking brain.
- Social isolation. People with hearing problems often become socially isolated. Studies have found that people unable to engage in conversation or who feel left out in social situations because they can’t communicate well tend to stop socializing. Social isolation is one of the most common risk factors for cognitive decline and dementia.
Hearing loss not only impacts mental health, it also affects physical health, relationships, income, and personal safety. For example, people with hearing problems have a history of falling, increasing the possibility of injury. Others are unable to react appropriately in emergency situations simply because they can’t hear alarms or sirens. That puts their personal safety at risk. Yet, fewer than 15 to 20 percent of those with significant hearing loss seek treatment, even hearing aids.
The good news is, it appears the damage done by hearing loss may be somewhat reversible. One study found that a small group of people between the ages of 65 and 85 with profound deafness in one ear benefited significantly from a cochlear implant (a surgically implanted device that bypasses the normal acoustic hearing process, instead replacing it with electric hearing) and auditory rehabilitation. Within one year of the implant, 80 percent showed significant cognitive improvement.
Experts say that the findings related to hearing loss most likely apply to other senses as well, including vision, smell, and touch. Studies have concluded that uncorrected vision problems also increase the risk of dementia.
The loss of hearing is one health problem that when left untreated creates additional health issues. For that reason, it is important to not only have your hearing checked on a regular basis, but also to seek treatment when necessary.
You brain will thank you!