You may have heard that the eyes are a window to the soul, but have you ever thought of the ears being a pathway to the brain? Well its true. Researchers have found there is a link between hearing and cognition – the brain’s process of perceiving and understanding. June is Alzheimer’s and Brain Health Awareness Month – Learn more about how prompt treatment of hearing loss could keep your brain function healthy.
How does hearing affect the brain in the first place?
Thanks to magnetic imaging, scientists can watch the brain and see how it activates in response to certain sounds. They've discovered that we don't hear with just one part of our brain. The process of hearing also stimulates other brain areas. Scientists believe there's a dual-track association between hearing and cognition. Sound activates the auditory cortex; the cerebral cortex and cognitive processes influence how we hear.
What happens to the brain when hearing is impaired?
Because there is a decline in sound stimuli and sensory deprivation, hearing loss can lead to structural and functional changes in the brain. These structural and functional changes can affect the brain's capacity to process and perceive sounds and may contribute to cognitive decline.
The brain is forced to compensate for these losses by activating alternative circuits. It enlists accessory neuron networks and that means increased cognitive effort is needed to weed out irrelevant sounds, like background noise, and more concentration is needed for hearing.
A high cognitive effort reduces the amount of brain resources available to process everything else. There's less of a cognitive reserve to tap into. So, things like concentration, memory and planning capacity may be affected. It's easier to get distracted. And constantly decoding and processing sounds can take up a lot of mental resources which can be tiring, eventually leading to potential withdrawal from social interactions.
This may explain why we see up to five times higher risk of dementia in people with untreated hearing loss. (Johns Hopkins study).
The significance of the hearing aid connection
The SENSE-Cog Project study stands out from previous research because it compares cognitive changes before and after hearing aid use in the same hearing-impaired individuals. (Older studies compared cognitive outcomes in hearing aid users and non-users.) Authors of The Hearing Review article “found compelling evidence to suggest a link between hearing aid use and slower cognitive decline.”
They also offer possible reasons for the connection between hearing aid use and reduced cognitive decline. According to one hypothesis, hearing aid use “may reduce depression, promote cognitively stimulating engagement (and) promote greater physical activity and/or self-efficacy, all of which protect cognitive function.” Another hypothesis is based on hearing aid use reducing the adverse impacts of sensory deprivation on brain function as mentioned above.
Good hearing health linked to good brain health
The SENSE-Cox Project study “suggests that improving (the) prevention, identification and treatment of hearing impairment may help to delay the onset of cognitive impairment and reduce the impending dementia epidemic,” states The Hearing Review article, which concluded with: “Good hearing health may be critical for good cognitive health.”
What action should you take to keep your hearing-brain function intact?
Here are two suggestions:
- Take our online hearing quiz today to get an indication of potential hearing impairment in everyday situations.
- Add hearing screenings to your preventive health routine to help you detect changes in your hearing allowing for prompt treatment. Check here to see if you may be covered for hearing care.