"Is your Brain shrinking?"

23 March 2015, 4:38PM
The National Foundation for the Deaf Inc. (NFD)

If you read little else today, we urge you to consider this excerpt from a blog titled “Listen up – or risk losing your mind” which is a fascinating read that was released this month by the Royal National Institute for the Deaf/Action on Hearing Loss in the UK written by their Jack Ashley Fellow Jan Schnupp.

“…[W]hile our society now recognizes the importance of adequate hearing in the young to encourage intellectual and social development, at the same time we are largely oblivious of a growing problem with hearing loss in older people. You might think that looking after the hearing of older people is perhaps less important. Good hearing and good communication are clearly especially important in the early years, when a person's intellect is first formed, but once our mind is developed and schooled and honed, surely it is no longer dependent on regular acoustic stimulation to stay sharp?

Sadly, such a relatively optimistic view of the resilience of the human mind is probably misplaced, as several recent studies suggest that adequate hearing seems to be important for staying mentally sharp later in life. Indeed, even only moderate hearing loss appears to be a major risk factor for a substantially accelerated cognitive decline in older people.

For example, a study by Lin and colleagues (3) found that older adults with moderate hearing loss were three times more likely to develop dementia than their peers with mild or no hearing loss. Another more recent study by Gurgel and colleagues (4) also found hearing loss to be an important risk factor for dementia. And even if you do not develop full-blown dementia, hearing loss may lead to a faster decline of important mental faculties as you age, such as a poorer memory and poorer scores at tests that measure your ability to concentrate and control your actions (5). As if that was not worrying enough, it has even been shown that the brains of older people with hearing loss shrink faster than those of their normally hearing peers (6).”

Does hearing loss actually cause cognitive decline?

Of course, sceptical readers of these lines might, justifiably, object that, just because hearing loss seems to go hand in hand with a decline in mental faculties, it does not necessarily prove that hearing loss causes this decline. Sure, such a causal link would be entirely plausible.

Our “mental muscles”, much like our physical ones, do seem to need regular work-outs to stay in good condition, and if bad hearing forces us to withdraw from the social interactions and banter that keep us engaged and sharp and limits our access to interesting news, then that deprivation might well be enough to lead to a measurable decline in mental faculties.”…

Louise Carroll, CEO of The National Foundation for the Deaf in New Zealand responds “Look,  if there is even a remote chance that hearing loss has a role to play in brain shrinkage, then surely getting a hearing test done to identify it and starting hearing loss rehabilitation to support our social interactions and brain connectivity would seem to be a really sensible thing to do. It seems the notion that ‘use it or lose it’ may be in play here.”

She recommends that all New Zealanders with hearing loss should be considering their options. “If you are one of the 1:6 who has some type of hearing loss who has not been hearing tested there is much that can now be done to improve your quality of listening and life, and hopefully supporting a lifetime of improved brain connectivity and better hearing for all.”

Hearing Week is 23-29 March, 2015. Do your brain a favour and get your hearing tested.

There is much we can all do to prevent hearing loss and to ensure we stay connected if we have hearing loss.  For more information check out www.nfd.org.nz

Follow-up: 021 0766 990

References:  Listen up – or risk losing your mind by Jan Schnupp, Jack Ashley Fellow, March 2015 Blog c/-Action on Hearing Loss, United Kingdom.
(3) Lin, F. R., Metter, E. J., O'Brien, R. J., Resnick, S. M., Zonderman, A. B. and Ferrucci, L. (2011) Hearing loss and incident dementia. Arch Neurol 68:214-220.
(4) Gurgel, R. K., Ward, P. D., Schwartz, S., Norton, M. C., Foster, N. L. and Tschanz, J. T. (2014) Relationship of hearing loss and dementia: a prospective, population-based study. Otol Neurotol 35:775-781.
(5) Lin, F. R., Ferrucci, L., Metter, E. J., An, Y., Zonderman, A. B. and Resnick, S. M. (2011) Hearing loss and cognition in the Baltimore Longitudinal Study of Aging. Neuropsychology 25:763.
(6) Lin, F. R., Ferrucci, L., An, Y., Goh, J. O., Doshi, J., Metter, E. J., Davatzikos, C., Kraut, M. A. and Resnick, S. M. (2014) Association of hearing impairment with brain volume changes in older adults. Neuroimage 90:84-92.