By Sloan Blanton
Brain Awareness Week (March 16-22, 2015) celebrates one of the most important organs in the human body and current progress and breakthroughs in brain research. While the brain literally affects every organ and bodily function, did you know hearing loss, especially when it goes untreated, can affect brain function and size? It can also affect quality of life. Depression rates are higher for those with hearing loss, as is the likelihood of emotional issues, such as anger and withdrawal, which can lead to poor mental health.
I was born with a sensorineural hearing loss in both ears so it is all that I have ever known. While I sometimes feel socially isolated because I am not always able to follow the conversations around me, and I also know my speech development has been directly affected by my hearing loss, my cogitative ability has been in no way impaired. However, several studies have found a correlation between aging, cognitive function, and hearing loss. For a long time, many researchers believed the two to be unrelated, but recent findings have proven otherwise.
From 2001 to 2007, the Health, Aging, and Body Composition study tested the hearing and cognitive abilities of nearly 2,000 adults between ages 75-84. In the study, those with hearing impairment lost cognitive abilities up to 40% more quickly than typical-hearing participants. Additionally, participants with hearing loss developed cognitive issues on average three years sooner than those with typical hearing.
Numerous theories dive into the relation between the brain and hearing loss, such as that the brain must work harder to process sounds when there is an inability to hear, which then takes the brain’s attention away from other cognitive functions. "We take for granted that processing sound is simple, but for the brain it's very energy intensive," Dr. Frank Lin, the assistant professor conducting the study, reported. "The most powerful computers in the world are no match for the sound-processing capabilities of the brain of a 3-year-old child."
The decline of cognitive ability impairs other brain functions, such as thinking and memory retention. Social isolation resulting from hearing loss can put the elderly at greater risk for dementia and other cognitive impairments. "It's early days yet, but we have seen that if you take an adult with typical hearing and put her in an MRI scanner while listening to garbled speech, the scans reveal that the brain has to spend extra energy to decode it," says researcher Jonathan Peelle.
In 2014, Neurolmage published Lin’s study on hearing loss possibly causing the brain to atrophy, like an unused muscle. Those who have had hearing loss for at least seven years or longer tended to have brains with small temporal lobes, making short- and long-term memory and processing meaning from sensory input difficult.
According to Healthy Hearing, a deeper understanding of hearing loss, both its causes and its effects, is crucial. The hope is that individuals with age-related hearing loss could benefit from cognitive and perceptual training exercises, and thus can have an improved quality of life. That includes better physical health, better mental health, improved relationships, and the ability to continue to engage in society. To make sure you're receiving the best care and are living the highest quality life possible, make an appointment with your hearing healthcare professional for your annual checkup; more than just your hearing will benefit.
Watch out for the “Break the Stigma” issue of Hearing Health Magazine this spring, which will include research on how addressing, and then treating, hearing loss leads to happier, healthier outcomes. If you're not already a subscriber to the FREE magazine, subscribe here.