Washington,  DC, October 10, 2013 — As research showing a link between hearing loss  and cognitive function mounts, the Better Hearing Institute is urging people to pay close attention to their hearing  and take a confidential online hearing check at www.hearingcheck.org in recognition of National Alzheimer’s Disease  Awareness Month in November. BHI is raising awareness of the relationship between  hearing loss and dementia, and is underscoring the importance of addressing  hearing loss for the benefit of overall cognitive function. Today, nearly 40  million people in the United States have some degree of hearing loss.

While the causality requires further  investigation, the increasingly evident link between hearing loss and dementia elevates  the urgency of diagnosing and treating hearing loss as soon as possible.

A study published earlier this year found that hearing loss is associated with  accelerated cognitive decline in older adults. Conducted by Johns Hopkins  otologist and epidemiologist Frank Lin, M.D., Ph.D. and other hearing experts, the  study found that older adults with hearing loss are more likely to develop  problems thinking and remembering than older adults whose hearing is normal. According  to a Johns Hopkins press release, volunteers with  hearing loss, undergoing repeated cognition tests over six years, had cognitive  abilities that declined some 30 to 40 percent faster than in those whose  hearing was normal. The researchers also found that the greater the hearing  loss, the greater the levels of declining brain function.

In a 2011 study, Lin  found that seniors with hearing loss are significantly more likely to develop  dementia over time than those who retain their hearing. The study also found  that the more hearing loss they had, the higher their likelihood of developing  dementia.

Exploring the hearing loss-cognition  connection

Other  studies have shown related findings, including several involving Brandeis  University Professor of Neuroscience, Dr. Arthur Wingfield. For many years,  Wingfield has been studying cognitive aging and the relationship between memory  and hearing acuity.

Wingfield  and his co-investigators have found that older adults with mild-to-moderate  hearing loss performed poorer on cognitive tests than those of the same age who  had good hearing. These findings have included a significant interaction  between hearing acuity and the level of difficulty listeners experience in  cognitively processing linguistic information—which is a higher-level brain  activity than simply interpreting the sound.

These  findings, Wingfield says, suggest that the listener’s hearing ability not only  affects their sensory processing of auditory information, but that it also  affects higher level linguistic processing.

The  study participants with hearing loss expended so much cognitive effort on  trying to hear accurately, Wingfield concluded, that it diminished their  ability to comprehend rapid speech and remember what had been heard.

More  recently, Wingfield, along with colleagues at the University of Pennsylvania  and Washington University in St. Louis, used MRI to look at the effect that hearing  loss has on both brain activity and structure.

Their  study found that people with poorer hearing had less gray matter in the  auditory cortex, a region of the brain that is necessary to support speech  comprehension. Wingfield believes that the participants’ hearing loss had a  causal role. He and his co-investigators hypothesize that when the sensory  stimulation is reduced due to hearing loss, corresponding areas of the brain  reorganize their activity as a result.

“The  sharpness of an individual’s hearing has cascading consequences for various  aspects of cognitive function,” said Wingfield. “We are only just beginning to  understand how far-reaching these consequences are.”

“Even  if you have just a mild hearing loss that is not being treated, you have to put  in so much effort just to perceive and understand what is being said that you  divert resources away from what you would ordinarily use to store what you have  heard in your memory,” Wingfield continued. “Cognitive load increases  significantly.”

As people  move through middle age and their later years, Wingfield suggested, it is  reasonable for them to get their hearing tested annually. If there is a hearing  loss, it is best to take it seriously and treat it.

For  more information on Alzheimer’s disease and National Alzheimer’s Disease  Awareness Month, visit the Alzheimer’s Association at www.alz.org.

Hearing aids can benefit people with  Alzheimer’s disease and hearing loss—and their caregivers   BHI  reminds people with Alzheimer’s disease and their caregivers that hearing health is an important factor in their quality  of life. The ability to communicate with the help of hearing aids can help enhance quality of life for individuals with Alzheimer’s and their caregivers.

BHI  advocates that hearing checks, hearing healthcare, and hearing aids when  appropriate be included in the regimen of care for people with Alzheimer’s disease.  Identification and remediation of hearing loss prior to the evaluation of  dementia also can help ensure a more accurate medical evaluation. BHI advocates  that a comprehensive hearing examination and hearing healthcare be part of the  diagnostic process.

For information about the 10 Early Signs and Symptoms of  Alzheimer’s, visit www.alz.org/10signs.