Teens and young adults often turnup the volume on their iPods or smartphones or stand near the speakers atconcerts or nightclubs, all in the name of having a good time. Even if theyrealize this could be damaging to their hearing, what neither they nor theirparents know is that this kind of behavior could be altering their brainfunction for life. A study in a 2018 issue of the journal eNeuro found thatyoung adults with subtle hearing loss-- a deficit that's so slight that they're not even aware of it (they reported they had normal hearing) --are placingdemands on their brains that don't normally occur until later in life.
In the study, researchers usedfunctional magnetic resonance imaging scans (磁共振成像扫描) to monitor brain activity,while healthy men and women listened to various sentences that varied in theircomplexity and the demands required to process and understand them. Beforeperforming the scans, the researchers tested the participants' hearing abilityand found that some of them had subtle hearing deficits, but were stillclinically in the normal range. What the researchers found is that listenerswith poorer hearing had activity in the right hemisphere of the brain, whichwas surprising because usually the left hemisphere of the brain is completelyresponsible for regulating and managing speech and language comprehension. Andthe altered brain function was still the same no matter how simple or complexthe sentence structure was.
The good news is that the brainis an amazingly plastic organ, meaning it has the ability to change and adaptthroughout life, explains Yune Lee, an assistant professor of chronic braininjury at Ohio State University. As people age, they begin to use more of theirright frontal brain to process language, but “we don't usually see that inyounger people," Lee explains. “That is worrisome because they start usingup these resources too early in life. It's like withdrawing money from a retirementaccount too early; these resources need to be kept for later in life."
The findings are especiallysignificant, says Sarah Sydlowski, audiology director of a Hearing ImplantProgram, because “hearing involves hearing sound but also processing it andextracting meaning in the brain. Exposure to loud sound can cause clinicaldamage to 'synaptic ribbons'- the connections between the sensory cells in theinner ear and the hearing nerve. People with this damage suffer from 'hiddenhearing loss' because often they will appear to have normal hearing on astandard hearing test, yet they may complain that they have difficultyunderstanding speech in noisy environments."
The long-term concern is that agrowing amount of evidence has shown a significant link between hearing lossand dementia. In fact, a review of studies in the June 2018 issue of Maturitasfound that hearing damage at midlife is associated with a 50 percent higherrisk of developing dementia later in life. The theory is “If you put all yourenergy into hearing, you drain cognitive resources that could be used for otherthings such as memory and attention," Lee says.
If you suspect that you'restruggling to hear clearly or process what you hear comfortably or accurately,get your hearing checked, including your ability to hear and understand speechagainst background noise, Sydlowski advises. The researchers don't recommendroutine hearing checks for adults, but the American Speech-Language-HearingAssociation calls for adults to be checked for hearing loss every decadethrough age 50, then every three years after that. The sooner you detect ahearing problem, the better; that way, you can take steps to handle it, whetherthat means modifying your environment to minimize ditractions, addingprotection for your hearing, doing auditory training (listening exercises) orconsidering a hearing device, Sydlowski says.
What should you do to protect your hearing according to the last paragraph?
A、To develop your ability to adjust to noisy environment.
B、To keep in touch with well -known hearing associations.
C、To detect hearing problems as early as possible.
D、To have your hearing checked frequently.
【正确答案】：C