In recent years the focus on hearing health care has shifted from the ears to the brain. One needs to only Google hearing loss and cognition to find dozens of articles in medical and hearing health care journals in the past few years.
Of particular interest is a recent article published ahead of print in Ear and Hearing February 22, 2019 by renowned Swedish and U.S. researchers Danielsson, Humes and Ronnberg who looked at the changes in the aging brain that affect speech understanding.
Reviewing 213 patients ages 18 to 86, these researchers showed degradation in hearing and deceleration in the speed of cognitive processing were a near certainty as we age. Other highly likely cognitive changes included poor auditory sequencing and impaired short-term memory.
In short, impaired hearing creates an imperfect message hampered by slow auditory processing that is sent to the aging brain that may jumble the order of the imperfectly heard message (due to auditory sequencing problems) making it difficult to create the requisite internal auditory loop that we use to comprehend auditory and visual information. This internal auditory loop is further damaged by reduced short term memory. As such, certain portions the message are damaged by the hearing loss, additional portions lost due to slow processing of rapid speech, additional parts jumbled in order and missing portions cannot be accurately reconstructed to due to limitations in short term memory.
From the above discussion the important question is “What can be done?”
First, it is essential to address impaired hearing with appropriately programmed hearing aids so that significant portions of the speech signal are not lost.
It is equally important to keep the aging brain active with social contacts, travel and music performance and cognitive exercise (which also requires properly corrected hearing).
Further, there is hope on the horizon as a new noninvasive cognitive treatment for short-term memory has been independently described by two different groups of researchers at Boston University and Northwestern University Feinberg Medical School. Specifically, both groups report that when they used electrical/magnetic currents targeted at specific areas of the brain, older people were able to carry out working memory tasks with an accuracy comparable with people in their 20s.
To summarize the appropriate treatment intervention, first evaluate/correct hearing loss with properly programmed hearing aids, keep the brain active through socialization, music performance and cognitive exercises and stay tuned for more information on the brain stimulation/short term memory treatments as described by the two independent groups of researchers.
Those interested in more information on this topic should attend the July 11, 2019 meeting of the Oregon Association for Hearing held at Corvallis Good Samaritan Hospital from 3:30 to 5 p.m. in Conference Room A. The public is invited, there is no charge, no personal information is solicited, there are no sales and complimentary refreshments are served. For further information call 541-754-1377.