Even the mildest cases of hearing loss may lead to cognitive decline, say researchers at New York-Presbyterian/Columbia University Irving Medical Center.
Previous research has shown that hearing loss increases the risk of cognitive decline and dementia. However, those earlier studies used 25 decibels (dB) as the threshold for hearing loss. As explained in a Reuters Health article, the new study used a 15 dB threshold, which is equivalent to the volume of a whisper or rustling leaves. With hearing loss at that level, older adults in the study had “clinically meaningful” cognitive decline.
Scientists are trying to understand why hearing loss is connected to cognitive decline. One possible explanation: The brain must devote so much attention to hearing that other cognitive functions don’t get “exercised.”
“People with worse hearing use so much more brainpower to decode the words that are said, they don’t get to process the meaning of what was said,” stated the study’s lead author, Dr. Justin Golub, assistant professor in the department of otolaryngology-head and neck surgery at New York-Presbyterian/Columbia University Irving Medical Center.
Can treatment of hearing loss improve cognitive functioning? Researchers are attempting to answer this question through a randomized controlled trial. Dr. Golub “suspects that people might be able to remain more mentally sharp if they started wearing hearing aids as soon as they started to have even mild issues with hearing,” says the Reuters Health article.