Untreated Hearing Loss Affects Brain Structure and Function

Recent studies shed light on the importance of timely treatment of hearing loss.
Most people believe that hearing loss is a condition that only affects their ears. In reality, untreated hearing loss can affect so much more, including brain structure and function.
According to a 2013 John Hopkins University study, hearing loss may increase the risk of cognitive problems and dementia.
A 2011 dementia study monitored the cognitive health of 639 people who were mentally sharp when the study began.
The researchers tested the volunteers’ mental abilities regularly, following most for about 12 years, and some for as long as 18 years.
The results were striking: The worse the initial hearing loss, the more likely the person was to develop dementia. Researchers say that there are plausible reasons for why hearing loss might lead to dementia — the brain’s hearing center, called the auditory cortex, is very close to the regions where Alzheimer’s first starts.
Hearing loss also has a noted link to brain shrinkage. Although the brain naturally becomes smaller with age, the shrinkage seems to be fast-tracked in older adults with hearing loss, according to the results of a study by Frank Lin, M.D Ph.D. through Johns Hopkins University and the National Institute on Aging. The report revealed that those with impaired hearing lost more than an additional cubic centimeter of brain tissue each year compared to those with normal hearing.
Those with impaired hearing also had significantly more shrinkage in particular regions, including the superior, middle and inferior temporal gyri, brain structures also responsible for processing sound and speech.
When a person is affected by untreated hearing loss, their auditory cortex becomes “impoverished” due to the lack of sound stimulation. Treating hearing loss in a timely matter, however, can help offset this.
These studies indicate the urgency in which hearing loss should be treated. “If you want to address hearing loss well,” Lin says, “you want to do it sooner rather than later.”