Everything you need to know about the common ear condition you’ve most likely never heard of.
It might sound a touch exotic, but sensorineural hearing loss (SNHL) is the most common form of hearing impairment. In Australia, it affects around 90% of people experiencing hearing loss. Onset of SNHL can be gradual or sudden, and it can be caused by a range of genetic, environmental and even medical factors.
Early symptoms can be as unassuming as tiny changes in the clarity or loudness of everyday sounds. So, at the slightest signs of hearing trouble, it’s worth getting your ears checked. Here we break down the causes, symptoms and treatments, so you know what to look for, and what to do if SNHL happens to you.
First, let’s start with the basics.
SNHL occurs when the tiny hair cells in the inner ear are damaged or when the hearing pathways to your brain become damaged or don’t function properly. The effects range from mild difficulty hearing certain sounds through to profound hearing loss and total deafness. Studies highlight that depending on the cause and severity, SNHL can be preventable and treatable.
You might think of your ears as the dangly bits on the sides of your head. But in terms of hearing and how they work there’s a whole lot more to it than that. So, let’s break down the anatomy.
Your ear has three main sections, which work together to help your brain process the sounds all around you:
Basically, the outer ear ‘catches’ sound waves and funnels them through the ear canal to the fully enclosed middle ear, causing the eardrum to vibrate. In the middle ear, the tiny chain of bones called the ossicles picks up on these vibrations and begins to move. In the inner ear we find the cochlea: a spiral-shaped membrane lined with thousands of microscopic hairs and filled with fluid.
When a tiny bone taps the cochlea’s membrane, the fluid moves. This stimulates the hairs and triggers nerve impulses, which then travel via the auditory nerve to the brain for interpretation into recognisable sounds. Pretty clever, right? Well, at least most of the time.
When all our ear processes work together in unison, our hearing sense is like a perfectly synchronised dance – with plenty of moving parts. But this level of complexity means parts or processes can sometimes break down or fall out of step. The outcome can be hearing loss. There are a few reasons why this might happen.
A major contender is called ‘conductive hearing loss’ – which is basically a blockage in some part of the outer ear. This can be caused by wax or fluid build-up, bony growths – as in, Surfer’s ear – or foreign objects. These types of blockages are generally pretty easy to fix. Sensorineural hearing loss, on the other hand, occurs deep in the inner ear, as the result of damage to either the cochlea or the auditory nerve. Because the affected parts of your ear are super close to your brain, there’s often no such thing as a simple fix.
In very rare circumstances, children will experience a ‘congenital’ variety of SNHL. This is usually present at birth, so doctors will be onto it right away – often treating with cochlear implants or hearing aids from the get-go. Unfortunately for the rest of us, the most common cause of SNHL is of the ‘acquired’ variety and occurs due to the natural ageing process.
Early symptoms might be as minor as a gradual reduction in the loudness or clarity of sounds. And you’ll most likely lose the high-pitched sounds first. Regular hearing tests are the best way to check the base level of your current hearing. From there, you may never fully recover the hearing you’ve already lost, but you can work towards preventing further damage.
There are a number of possible SNHL causes and factors to consider. These include:
Obviously, there’s not a lot you can do about things like family history or infections. But you can preserve the hearing you’ve got with prevention techniques, like always wearing earplugs or muffs in loud environments. Although being aware of which potential at-risk groups you may fall into won’t stop the onset of SNHL, it will give you extra incentives to get a hearing health check.
You’re by no means alone. It’s a popular group, consisting of around one in seven of all Australians over 65. The bad news is: any damage you’ve already done is permanent. But the good news is: hearing aids can help you elevate the hearing you’ve still got.
If you’re over 50, there’s a good chance you’ll know somebody who wears them. So picking their brains about the benefits might be a good way to break the ice. Then, when you’re ready, talk to a hearing health professional about your needs, and they’ll be able to customise treatments to meet them.
Changes in your hearing due to SNHL as you get older are normal. And, as millions of Australians will attest, there’s no reason to let hearing loss prevent you from doing the things you love. Acting as soon as you notice any changes will give you the best chance to protect what you’ve got and prevent further damage. Start with a hearing test, and from there you can explore a variety of different hearing aid solutions that can help make your surrounding sounds just that little bit clearer. One specific test is the OAE hearing test (otoacoustic emissions), which can be used to diagnose sensorineural hearing loss because – for instance in children.