She had been living with Alzheimer’s disease for twelve years.
When she attended a routine hearing assessment, the audiologist concluded that she had a significant hearing loss — and she left with an order for over £3,000 worth of hearing aids.
It’s a story that raises an important question. Not about whether she needed hearing aids, but about whether the assessment itself told the whole story.
To understand why, we need to look at the difference between hearing and processing — and why, for someone living with dementia, those two things can be very easy to confuse.
Hearing Is Not Affected by Dementia
This is one of the clearest messages in dementia care education, and it’s worth stating plainly.
Dementia does not affect the ears. The physical structures responsible for detecting sound are not damaged by dementia. A person living with dementia is not deaf because of their dementia.
Some people living with dementia will also have hearing loss — but that’s a separate matter, usually related to age, and not something caused by the dementia itself. Having dementia does not guarantee hearing loss, and having hearing loss does not mean the ears are the whole story.
So Why Does It Sometimes Look Like Deafness?
Because hearing is not just about the ears.
When sound enters the ear, it’s converted into signals that travel to the brain. The brain then receives those signals, makes sense of them, works out what they mean, and decides how to respond.
That second part — the interpretation — is where dementia has a significant effect.
Research published in the journal Brain describes listening as a highly active cognitive process, noting that most natural auditory environments comprise mixtures of sounds that change over time, and that the incoming signal must be broken down into meaningful components — separating voices from background noise, identifying speech features, making sense of what’s been heard. All of that work happens in the brain, not the ears.
When dementia affects the brain’s auditory processing centres — particularly in the temporal lobes — a person may be physically capable of detecting a sound, yet struggle to make sense of it. They may hear a voice but lose track of the words. They may register that someone is speaking but be unable to follow the meaning. They may hear a sound and simply not connect it to any action they need to take.
From the outside, this can look exactly like hearing loss. But the ears may be working perfectly well. The challenge lies in what the brain is able to do with the information once it arrives.
Central Auditory Processing: A Brain Story
The research on this is both clear and significant.
A systematic review published in the journal Cells found that central auditory processing is impaired in people diagnosed with Alzheimer’s disease and its preclinical stages, and may manifest many years before clinical diagnosis.
Importantly, this is not an ear problem — it is a brain problem. Research has identified that changes in the central auditory system start in the temporal lobe and may produce deficits in speech processing, and that central auditory processing difficulties may present as an early manifestation of Alzheimer’s disease, preceding clinical diagnosis by between five and ten years.
This matters because it reframes what we’re seeing. When a person living with dementia struggles to follow conversation, mishears words, or doesn’t respond to sounds in the way we expect, it may not be a sign that their ears are failing. It may be an indicator of the same brain changes that are driving all the other changes we observe — and it may have been present, quietly, long before the dementia was even diagnosed.
It is the brain that is changing, and the brain is responsible for far more than memory.
The Problem With a Standard Hearing Test
A standard hearing assessment typically works like this: the person wears headphones, sounds are played at varying volumes and frequencies, and they press a button each time they hear something.
It’s a simple enough task — but only if you can follow and retain the instructions, understand where you are and what’s being asked of you, and consistently connect the hearing of a sound to the pressing of a button in the moment it occurs.
Research published in JAMA Otolaryngology found that because hearing is a perceptual process, the criterion standard for hearing assessment — audiometry — requires active and interactive behavioural responses from patients, and that individual differences in cognitive ability may affect test results. While the same study found that hearing assessments can be reliable in people with mild dementia under ideal conditions, the picture changes significantly as dementia progresses.
A review of hearing assessment in dementia published in Frontiers in Aging Neuroscience noted that some adults with moderate and severe dementia are able to be assessed with pure-tone audiometry, but many people living with dementia may benefit from adaptations to standard audiometric procedures.
For the woman in our opening story — twelve years into her Alzheimer’s journey — the standard test presented a significant challenge on every cognitive level. She may not have known where she was or why she was there. She may have been unable to hold the instruction in mind. She may have heard a sound and simply not connected it to the required response. She may have been disoriented, anxious, or overwhelmed.
From the audiologist’s perspective, she wasn’t pressing the button — so the conclusion was that she couldn’t hear the sounds.
But there is another explanation entirely, and it has nothing to do with her ears.
What the Test Couldn’t Separate Out
A standard hearing test measures whether a person responds to sound. What it cannot easily tell us is why they’re not responding.
Is it because the ears aren’t detecting the sound? Or is it because the brain — affected by over a decade of Alzheimer’s disease — is unable to process the task, retain the instruction, or connect hearing a sound to pressing a button?
In someone living with advanced dementia, those two things are extremely difficult to separate using a standard behavioural assessment. The test was designed for people who can understand and follow a sequential task. When that ability is significantly affected, the results need to be interpreted with great care — and ideally by someone who understands what the dementia itself is affecting.
This doesn’t mean hearing assessments have no place for people living with dementia — they do. It means the results only make sense when considered alongside a full understanding of the person and where they are in their dementia journey.
What This Means Day to Day
Understanding that hearing itself is not affected by dementia — but that the brain’s ability to process and interpret sound is — changes how we make sense of what we observe.
If a person seems not to hear you, the first question isn’t always whether their ears are working. It may be whether the brain is able to process and respond to what it’s receiving — whether the environment is too noisy, whether the instruction was too complex, whether there was enough time and stillness for the message to land.
Speaking clearly and at a steady pace, reducing background noise, facing the person directly, keeping language simple, and allowing time for processing — these aren’t just strategies for hearing loss. They’re strategies that support the brain’s ability to interpret and respond.
And they can make an enormous difference.
A Final Thought
The woman who left with £3,000 of hearing aids may well have had some degree of hearing loss alongside her dementia — the two can absolutely coexist, and hearing aids may even have helped her to some extent.
But what the assessment couldn’t account for was twelve years of Alzheimer’s disease affecting her brain’s ability to understand where she was, follow an instruction, and respond to a sound in the way the test required.
Dementia doesn’t affect the ears. It affects the brain — and the brain is responsible for far more than simply detecting that a sound exists. It makes sense of it, gives it meaning, and decides what to do next.
That distinction matters. For assessments, for communication, and for the way we understand and support the people in our care.