Age-related difficulty recognizing words predicted by brain differences

May 12, 2009

Older adults may have difficulty understanding speech because of age-related changes in brain tissue, according to new research in the May 13 issue of The Journal of Neuroscience. The study shows that older adults with the most difficulty understanding spoken words had less brain tissue in a region important for speech recognition. The findings may help explain why hearing aids do not benefit all people with age-related hearing difficulties.

Although some hearing loss can be a normal part of aging, many complain about difficulty understanding speech, especially in challenging listening conditions like crowded restaurants. Research has suggested that this decline in speech recognition is independent of hearing loss.

To identify what causes the decline in , the researchers, led by Kelly Harris, PhD, at the Medical University of South Carolina, scanned the brains of 18 younger adults (19-39 years old) and 18 older adults (61-79 years old) as they tried to identify words in listening conditions that varied in difficulty. During a challenging listening condition, the older adults repeated fewer words correctly than did the younger adults, consistent with previous studies.

Harris and her colleagues found that structural differences in the brain's auditory cortex predicted performance on the task, even when they controlled for . The older adults who had the most difficulty recognizing words also had the least brain volume in a region of auditory cortex called Heschl's gyrus/superior temporal gyrus. However, the relationship between the ability to identify words and the volume of auditory cortex was also present in younger adults.

"The results suggest an intriguing possibility — that adults with low volume in auditory cortex may be at greater risk for problems understanding speech later in life," said the study's senior author, Mark Eckert, Ph.D., at the Medical University of South Carolina.

"Depressing though it may be, the new research by Harris and colleagues has shown that as we develop age-related deafness, investing in newer and more powerful hearing aids is only part of the solution. The , and particularly the auditory cortex, also needs repairing, and that is not so easy to achieve," Richard Wise, MD, PhD, at Imperial College, London, who was unaffiliated with the study.

More information: www.jneurosci.org/

Source: Society for Neuroscience (news : web)

Explore further: Know the brain, and its axons, by the clothes they wear

add to favorites email to friend print save as pdf

Related Stories

Genes influence age-related hearing loss

Nov 14, 2007

A new Brandeis University study of twins shows that genes play a significant role in the level of hearing loss that often appears in late middle age. The research, in the Journal of Gerontology: Medical Sciences, examined geneti ...

Study: Our brains compensate for aging

Apr 04, 2006

Yale University and University of Illinois scientists say they've determined our brains compensate for aging by becoming less "specialized."

Lend me your ears -- and the world will sound very different

Jan 14, 2008

Recognising people, objects or animals by the sound they make is an important survival skill and something most of us take for granted. But very similar objects can physically make very dissimilar sounds and we are able to ...

Seeing While Hearing Speeds Brain's Processing of Speech

Jan 15, 2005

While the R&B classic "I Heard It Through the Grapevine" advises you to "believe half of what you see and none of what you hear," a University of Maryland study has found that seeing and hearing together speed up the brain's ...

Mandarin language is music to the brain

Dec 12, 2006

It’s been shown that the left side of the brain processes language and the right side processes music; but what about a language like Mandarin Chinese, which is musical in nature with wide tonal ranges"

Recommended for you

Know the brain, and its axons, by the clothes they wear

Apr 18, 2014

(Medical Xpress)—It is widely know that the grey matter of the brain is grey because it is dense with cell bodies and capillaries. The white matter is almost entirely composed of lipid-based myelin, but ...

Turning off depression in the brain

Apr 17, 2014

Scientists have traced vulnerability to depression-like behaviors in mice to out-of-balance electrical activity inside neurons of the brain's reward circuit and experimentally reversed it – but there's ...

Rapid whole-brain imaging with single cell resolution

Apr 17, 2014

A major challenge of systems biology is understanding how phenomena at the cellular scale correlate with activity at the organism level. A concerted effort has been made especially in the brain, as scientists are aiming to ...

User comments : 0

More news stories

Cancer stem cells linked to drug resistance

Most drugs used to treat lung, breast and pancreatic cancers also promote drug-resistance and ultimately spur tumor growth. Researchers at the University of California, San Diego School of Medicine have discovered ...

Finnish inventor rethinks design of the axe

(Phys.org) —Finnish inventor Heikki Kärnä is the man behind the Vipukirves Leveraxe, which is a precision tool for splitting firewood. He designed the tool to make the job easier and more efficient, with ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.