The Link Between Dementia and Hearing Loss
September 17, 2019
Over recent years, several academic studies have drawn connections between hearing loss and the onset of dementia.
Hearing loss is one of the trials many people are forced to endure as they enter into old age. As opposed to people born with deafness or hearing deficiencies, people who lose their hearing in later life often fail to adapt their lifestyles accordingly. This can lead to a myriad of social and psychological problems.
This article explores the connection between hearing loss and dementia and discusses the possible prevention and treatments available.
Anyone who has lived in an urban setting has also lived with noise. In the modern era, this is truer than ever before. Whether it be traffic noise, the hum of machinery, the ultra-loud music we enjoy on the weekend, or the industrial noise that comes with working in certain professions, we are subjected to noise on a daily basis.
Most of these noises are not loud enough to harm our hearing, they fall into the general safe zone of 85 decibels or less. However, if you are regularly subjected to noise over 85 decibels you are putting your ears at risk. Anything over 120 decibels and you could damage your hearing immediately.
There have been massive strides made in workplace safety regulations over the last 50 years. Earplugs and earmuffs are now legally enforced on job sites where noise is frequently at dangerous levels. On top of that, our common sense has matured to understand the danger inherent with noise. As a result, people are now learning to protect themselves against the hazard of noise.
Hearing loss leads to changes in brain activity
However, for those who do experience hearing loss, a new problem has been identified. Researchers at Ohio State University have recently drawn a connection between hearing loss and brain activity. Even more striking is the fact that the hearing loss is in young adults and the changes in brain activity are the sorts of changes we associate with much older people. In other words, the study has noted a correlation between hearing loss and the type of brain adaptation that can lead to dementia.
As the study’s lead researcher, Yune Lee points out: "hearing loss, even minor deficits, can take a toll on young people — they're using cognitive resources that could be preserved until much later in life,". The hearing loss forces the brain to work harder which takes a toll on its overall functioning.
One of the study’s alarming findings was that young adults only needed a very minor impairment for it to affect their brain functioning. Even subtle hearing deficiencies had them processing messages in a different way to their peers; a way that was similar to the process of elderly people.
MRI imaging of the brain shows that those who hear perfectly process all sound in the left hemisphere of the brain. However, those with hearing impairments - slight or severe - also engage the right hemisphere of the brain for sound processing.
As Lee explains "this isn't about the ear — it's about the brain, the cognitive process, and it shouldn't be happening until people are at least older than 50,". As people are forced to expend more effort processing language, the right and frontal areas of the brain are brought into action, and this is the case even with a mild hearing loss.
People with hearing loss are twice as likely to have dementia
"Their brains already know that the perception of sound is not what it used to be and the right side starts compensating for the left,"Lee notes. The worry is that as these issues worsen they could speed up the onset of neurodegenerative diseases like dementia. Not without good reason, previous research has shown that people with hearing loss are twice as likely to have dementia; with severe hearing loss, they are five times as likely.
The consequences of damaging your hearing go beyond the actual difficulty of understanding speech. Because of the holistic nature of the body, and the compensation that the brain will make in order to hear, damaged hearing can lead to mental degeneration.
Protect against hearing loss at every opportunity
The message is striking, protect your ears at every opportunity. If you are regularly immersed in a noisy and loud environment you should take the proper precautionary measures. This is the same for musicians as it is for people operating heavy machinery. Have a doctor test your ears regularly and make sure any issues are treated properly.
Wearing hearing aids is essential if you have endured hearing loss. There are many great brands and styles now available that can make the experience as comfortable as possible. Keeping the brain healthy is vitally important.