Over the past several years, studies have indicated a connection between hearing loss and cognitive impairment. While this connection may not be intuitive, mounting evidence from studies across different age groups shows that such a connection does exist. The majority of past studies focused on older adults, and the findings indicated connections between increased prevalence of dementia and hearing loss, as well as increased difficulty in verbal comprehension and working memory. Determining the causal relationship of such findings is difficult; for example, hearing loss can increase the risk of dementia through reduced social interaction and increased stress and depression. However, it has also been theorized that hearing loss contributes to dementia and other cognitive impairment by draining neural resources through increased listening effort; these neural resources are then unable to be allocated to other cognitive processes.
Although several studies, including those referenced above, focused on hearing loss and cognitive impairment in older adults, one recent study instead examined this connection in younger adults. In this study, researchers monitored the brain activity of 35 young healthy adults between the ages of 18-41 in response to sentences of varying syntactic complexity. As expected, the classic language network of the brain, located in the left frontotemporal cortices, displayed greater activity when the test subjects were given sentences of greater complexity. However, not all of the findings were as expected; when the test subjects were given complex sentences, increased brain activity also emerged in the right anterior prefrontal cortex, showing a negative correlation with hearing acuity. This type of right frontal activity, indicating brain plasticity, has been previously documented in older adults during language tasks, but it had not been documented in such young, healthy adults. After controlling for age, the right frontal cortex activity still showed a strong association with hearing acuity.

While further longitudinal studies are needed to investigate the connection between hearing loss and cognitive ability in younger adults, these findings are still a strong indicator that hearing loss can contribute to cognitive impairment in younger adults. It is hypothesized that the increased brain activity, signaling brain elasticity, may imply depletion of neural resources in the future, ultimately leading to a greater risk of dementia.

So what can be done, especially for young adults, to avoid hearing loss-related cognitive impairment? Young adults are increasingly exposed to noise at dangerous levels on a regular basis; in fact, according to surveys, more than 90 percent of college students use personal music devices, and almost half of these students listen to their music at high volumes that exceed safety standards for occupational noise exposure. This increases the risk of early hearing loss in adolescents and young adults. To reduce the risk of hearing loss and associated cognitive impairment, it is essential for young adults to avoid exposure to such high volumes of music and other noise. By protecting their hearing, young adults can reduce the risk of dementia, other forms of cognitive impairment, and various negative effects on their wellbeing connected to hearing loss.

For more information on how you can protect your hearing and how to treat hearing loss, please contact us at Cody Audiology Clinic.