The Hidden Impairment: What Everyone Should Know About Hearing Loss

Hearing loss is often called a “hidden” impairment — it creeps up so gradually that the person losing their hearing is usually the last to notice. In this conversation, Lisa Leong sits down with Sharon Cowan, Clinical Team Lead and Senior Audiologist at Melbourne Audiology Centre, to unpack the early warning signs of hearing loss, what actually happens during a hearing test, how loud is “too loud,” and why untreated hearing loss has been linked to cognitive decline. Sharon also answers listener questions on sudden hearing loss and shares how far hearing aid technology has come.

Key moments

• Family notices first — the person losing their hearing rarely spots it themselves; it’s usually a partner or family member who notices repeated “what did you say?” moments.
• What a hearing test involves — a trip to an audiologist’s sound booth, pressing a button to register sounds across a range of frequencies.
• Presbycusis explained — age-related hearing loss causes roughly one decibel of loss per year, mostly affecting high frequencies and the ability to filter background noise.
• Protecting your hearing — sustained exposure above 85 decibels can cause permanent damage; every extra 3 decibels halves the safe exposure time. Everyday examples: a food processor can hit high decibels but only briefly; a loud concert can reach 120–140 decibels, comparable to a jet engine.
• Sudden hearing loss is a medical emergency — sudden sensorineural hearing loss needs urgent attention from a GP or ENT, since early treatment can prevent lasting damage.
• The dementia link — untreated hearing loss is associated with faster cognitive decline, along with depression and diabetes; hearing aids can help protect memory and concentration.
• Modern hearing aids — today’s devices range from invisible in-ear models to sleek behind-the-ear designs, with direct Bluetooth streaming for calls, music, podcasts and even remote microphones.
• Choosing a provider — look for an independent audiologist who isn’t tied to a single manufacturer, so you get unbiased advice.

Listen to the Full Interview

Lisa: You mentioned that if it’s gone, it’s gone. Is there anything we can do to lower the risk of our hearing deteriorating too much?

Sharon: Yes, definitely. We know that repeated exposure to loud sounds — anything above 85 decibels over a maximum period of around eight hours — can cause permanent damage. We also know that every three decibels, the safe exposure time halves, so if you’re exposed to sounds over 120 decibels, even seconds of exposure can cause permanent damage. Safe levels sit around 70 decibels, which is normal conversation — normal traffic noise and ambient sounds are fine. But if you’re using noisy equipment like lawnmowers or power tools, you need adequate hearing protection. Same at a loud concert or gig — we recommend good-quality musician earplugs, which have attenuators that filter sound down to a safe level. And use common sense: look at where the noise sources are and try to avoid them — don’t stand next to a noisy amplifier, and in a restaurant, try to get seating away from the main noise sources.

Lisa: You’ve mentioned a couple of decibel levels — 85 and 120. Can you give us an indicator of what causes a noise to hit 85 decibels? I have no idea how loud that actually is.

Sharon: Sure — some examples. A piece of equipment like a food processor.

Lisa: Really?

Sharon: If you turn it up, yes. Some food processors go really high. But that tends to only last seconds — like if you’re blending a smoothie — so it’s okay because it’s not over that eight-hour period. 120 to 140 decibels is quite loud — that could be loud music at a concert. 140 is like a jet engine taking off — really, really loud.

Lisa: I do get worried at those concerts — it seems way too loud.

Sharon: It can be. That’s why we recommend musician plugs, or even just a foam insert, to protect your hearing in those environments.

Lisa: I’ve got a text here — not sure you can help with this one. The listener says: “I had a hearing test six months ago and had perfect hearing. Then I woke up a month ago with no hearing in my right ear. It’s come back a bit, but I’ve had my ears checked — no wax buildup. I’ve taken allergy tablets, but it’s still about 60% hearing loss. What’s my next step, please?”

Sharon: I’d say see an audiologist to look at what we can do to help restore and improve the hearing. There’s a condition called sudden sensorineural hearing loss, which can happen very fast — we’re unsure of the causes, but it’s a sudden drop in hearing, and it’s considered a serious medical condition. If that happens, we recommend seeing your GP, or even an ENT, quickly to get treatment — early treatment can prevent some of the serious damage. Sometimes there’s spontaneous recovery too, but that can take several months.

Lisa: But obviously, to rule out anything serious — see your doctor or audiologist to get it properly diagnosed. We’re talking about hearing loss with Sharon Cowan, Clinical Team Lead and Senior Audiologist at Melbourne Audiology Centre, on Head to Toe. Is it true that hearing loss can lead to dementia?

Sharon: Yes — hearing loss is associated with a number of comorbidities. There’s an association with cognitive decline, dementia, even things like depression and diabetes. We know untreated hearing loss can accelerate cognitive decline, which is why we recommend hearing aids — they help improve memory and concentration.

Lisa: Tell us about how good the modern ones are — sometimes you can’t even see them.

Sharon: Correct. Hearing aid design has changed dramatically over the years. There’s always been a stigma about wearing them, but I’m pleased to see more people wearing devices these days — you walk down the street and see AirPods, headphones, all sorts of Bluetooth devices, and hearing aids too. It would be great if it became more socially acceptable, because an untreated hearing loss really impacts your quality of communication and quality of life.

Lisa: It should be like glasses, shouldn’t it?

Sharon: Exactly — glasses have become a fashion statement. Hearing aid design now covers a whole range, from ones that sit completely in the ear and are invisible, to ones that go behind the ear and are still fairly discreet. There are some you can see, but as a community we need to be a bit more accepting — if people can’t hear, they need a device, and there’s nothing wrong with that.

Lisa: I did hear about someone who was able to hook up their partner from across a table in a restaurant, so they had a direct line into their hearing aid. I thought that was really cute. Can technology do some pretty unique things now?

Sharon: It’s changed dramatically. There’s a lot of wireless connectivity and direct streaming these days — pretty much everything you can think of, a hearing aid can do. You can stream phone calls directly into your hearing aid so you hear crisp and clear, stream podcasts and music, ask your hearing aids for instructions, connect to virtual assistants, and with a remote microphone, take the signal straight from your partner into your hearing aid. The technology is there to help in almost any situation.

Lisa: Before you go, Sharon — if someone’s interested in doing a hearing test, is there a way to tell the difference between providers? What should we look out for?

Sharon: I’d recommend going to an independent audiologist. They have no bias toward any particular manufacturer, so they fit from a range of products and give you an unbiased opinion on what management you actually need.

Lisa: Thank you — thanks so much, Sharon, for helping.

Sharon: No problem.

Sharon Cowan is Clinical Team Lead and Senior Audiologist at Melbourne Audiology Centre.