Say what? — A sad circle of dysfunction
Not so good news for people with hearing loss:
A new study by researchers from the Perelman School of Medicine at the University of Pennsylvania shows that declines in hearing ability may accelerate gray mater atrophy in auditory areas of the brain and increase the listening effort necessary for older adults to successfully comprehend speech.
When a sense (taste, smell, sight, hearing, touch) is altered, the brain reorganizes and adjusts. In the case of poor hearers, researchers found that the gray matter density of the auditory areas was lower in people with decreased hearing ability, suggesting a link between hearing ability and brain volume.
“As hearing ability declines with age, interventions such as hearing aids should be considered not only to improve hearing but to preserve the brain,” said lead author Jonathan Peelle, PhD, research associate in the Department of Neurology.
“People hear differently, and those with even moderate hearing loss may have to work harder to understand complex sentences.”
© 2011 News & Publications, Mild Hearing Loss Linked to Brain Atrophy in Older Adults, Penn Study Shows: Early Intervention Could Prevent Slide toward Speech Comprehension Difficulties, Penn Medicine (31 August 2011) (paragraph split)
Citation — not yet available
As of 31 August 2011.
Not really a surprising finding
It fits with what we already know about neural development and atrophy. What isn’t used tends to go away.
But questions remain
Off the cuff, one would think that atrophy would only occur in those areas devoted to processing lost frequencies. That is not exactly the same as saying whole-system processing of speech disappears, which would imply that our ability to integrate what we still can hear weakens, as well.
On the other hand, one can imagine that losing one’s ability to integrate key portions of the frequencies involved in speech would leave interpretive gaps that would amount (practically speaking) to the same thing.
Implications for primary care — talk to your doc
This is the kind of research that arguably should prompt patient-initiated conversations with primary care providers.
Heretofore, hearing loss simply meant that one couldn’t hear as well as one did before, usually within an identifiable spectrum of frequencies.
This new research implies that — even if the patient is coping well at present — her ability to do so in the future may decline as the auditory cortex deteriorates from non-use.
This is excellent news for hearing aid manufacturers.