精东影业

A new study found that the brain鈥檚 ability to process sound starts to slow as early as middle age.

The research, led by Vishakha Rawool, Ph.D., CCC-A, associate dean for research in 精东影业鈥檚 Waters College of Health Professions (WCHP) and professor in the Department of Clinical Sciences, offers insight into a common frustration for many adults: being able to hear sounds clearly but struggling to follow fast conversations, especially in noisy environments.

To understand what happens inside the brain鈥檚 hearing pathways, researchers compared two age groups: young adults between ages 18 to 27 and middle-aged adults between 45 to 59.

The team measured how quickly the brain and the ear work together using a middle-ear reflex that automatically contracts when it hears loud sounds. By tracking how this reflex responded to a rapid series of clicks, they determined how efficiently the brain鈥檚 auditory system processed sound.
鈥淲e wanted to catch the very first signs of change,鈥� Rawool said. 鈥淏y the time someone has significant hearing loss, they may already be dealing with social isolation, anxiety or difficulty at work.鈥�
The results showed that the middle-aged group鈥檚 brain response was slower than that of the younger adults. This difference suggests that the brain鈥檚 鈥渉earing speed,鈥� or how rapidly it can process fast sounds, naturally begins to decline when a person reaches middle age.

鈥淯sing an objective measure that is not affected by cognitive decline, the results show that the central auditory system starts to slow down by midlife,鈥� stated Rawool. 鈥淭his slowing may require greater listening/cognitive effort, perhaps unconsciously, while listening to fast speech, reverberant speech and speech in noisy surroundings.鈥�

The study also affirmed that this slowdown was not related to the ability to hear sounds, but instead it was linked to changes in how the brain itself processes sound. According to Rawool, loss in hearing speed can leave people feeling as though they are trying to read a sentence with missing letters.
鈥淲e need to stop thinking of hearing health as something that only matters when you鈥檙e 70,鈥� Rawool said. 鈥淲e should be checking in on 鈥榟earing speed鈥� in our 40s and 50s.鈥�
Rawool and her team hope that publishing this research will lead to training programs or therapies that strengthen the brain鈥檚 auditory processing in adults ages 45 to 59, potentially helping to reduce listening fatigue and communication difficulties later in life.

The research also suggests the need for creating the best listening environments, such as quiet spaces with low reverberation, for all listeners to reduce fatigue.
鈥淚f you feel exhausted after a long day of listening, it鈥檚 not just in your head,鈥� she said. 鈥淵our brain may simply be working harder鈥攁nd that鈥檚 something we can begin to address.鈥�
The study was partially supported by West Virginia University鈥檚 Grace Clements Communication Sciences & Disorders Research Endowment Award.

The full article is available in the International Journal of Audiology: