When forgetting matters, and when it does not

Missing words, names that arrive late, a familiar route that feels less automatic: the most common worry in later life is memory, and the question underneath is whether this is the start of dementia. That question cannot be answered from the inside. What can be worked out clinically is which of three categories the change fits, normal age-related change, mild cognitive impairment, or dementia, and which patterns are worth bringing to a GP, since several treatable conditions can look like dementia and are not.

Written and reviewed by Matthew Hallam, Registered Psychologist (AHPRA PSY0002471369). 10 min read. Published 7 June 2026. Last reviewed 7 June 2026. Next review 7 June 2027.

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What changes about memory with age, and what does not

A great deal of what older adults experience as memory loss is age-related cognitive change, which is its own thing and not the same as dementia. The processing speed slows. The retrieval of names becomes less automatic. The ability to hold multiple things in mind at once narrows. Recent events take a little longer to consolidate. These changes are normal, they begin earlier than most people realise, and they are not in themselves signs of any disease (Salthouse, 2019).

What does not change, in the same way, is the underlying memory for material that has been well-learned. The story of how the person met their partner. The way to do a familiar task. The recognition of long-known faces. These remain available in age-related cognitive change. When they begin to slip, the picture has changed, and the change is worth attention.

The current Lancet Commission on dementia prevention, intervention, and care identifies fourteen modifiable risk factors that, taken together, are associated with around forty-five percent of dementia cases globally (Livingston et al., 2024). The list includes hypertension, hearing loss, physical inactivity, social isolation, depression, smoking, and several others. This matters for the present guide because it indicates that a substantial portion of cognitive decline in later life is not a fixed trajectory. It is shaped by modifiable factors that respond to attention. The point is not to add anxiety. The point is that the trajectory of cognition in later life is, to a meaningful extent, an active picture rather than a passive one.

The differential: normal ageing, MCI, and dementia

There are three categories that need to be told apart, because the response to each is different.

Normal age-related cognitive change is what was described above. Slower retrieval, occasional name-loss, reduced multi-tasking. The pattern is consistent with day-to-day life functioning. The person manages their own affairs. The forgetting is noticed by the person themselves more than by the people around them.

Mild cognitive impairment (MCI) is the intermediate category. It is defined by cognitive change that is greater than expected for age but does not meet the threshold for dementia. Memory or other cognitive functions are measurably reduced on testing, but day-to-day functioning is largely preserved. The outcomes from MCI are heterogeneous. A recent systematic review and meta-analysis of 89 studies, with mean follow-up of around five years, found that roughly four in ten people with MCI seen in clinical settings progressed to dementia, while in community samples the figure was closer to one in four. Roughly half remained stable. A meaningful proportion, around one in eleven in clinical samples and closer to one in three in community samples, returned to normal cognition (Salemme et al., 2025). MCI warrants assessment. It does not warrant a prediction.

Dementia is defined by cognitive decline sufficient to interfere with day-to-day functioning. The person can no longer manage some part of their independent life, whether that is medications, finances, the cooking, or the safe operation of the car. The cognitive change is consistently observable, and the impact on life is consistently observable too. Dementia has many forms: Alzheimer's disease is the most common, but vascular dementia, Lewy body dementia, frontotemporal dementia, and others have their own features and trajectories. Telling them apart is a clinical task, not a self-assessment one.

The three categories are normal age-related change, mild cognitive impairment, and dementia. The differences between them are well-defined clinically. They cannot be reliably distinguished from inside the experience of the person noticing the change. This is what assessment is for.

What is worth bringing to a GP

The clinical literature is reasonably consistent about which patterns warrant a workup. Without trying to replicate clinical decision-making, the following changes, sustained over weeks or months rather than appearing on a single bad day, are worth bringing to a GP.

A noticeable change in cognition that other people are seeing, not only the person themselves. Difficulty with tasks that used to be automatic, such as managing the household finances, following a familiar recipe, or operating familiar appliances. Getting lost in familiar places. Asking the same question repeatedly in a single conversation without recognition that it has just been asked. Changes in personality or judgement that family members notice. New difficulty finding common words to the point that conversation slows. Difficulty recognising people who should be familiar.

None of these is, on its own, a diagnosis. Some have causes that are unrelated to dementia, including depression, sleep disturbance, medication side effects, thyroid problems, vitamin B12 deficiency, urinary tract infections in older adults, and a range of other treatable conditions. This is precisely why the workup matters. The picture has to be looked at as a whole, and several treatable causes can produce a picture that looks like dementia and is not.

What a workup typically involves

A GP-led workup for cognitive concern usually begins with a careful history, often including a family member who can speak to changes over time. It typically includes a brief in-clinic cognitive screen, blood tests to rule out treatable conditions that mimic cognitive decline, a review of medications, and a screen for depression, which can present in older adults with prominent cognitive features. Where appropriate, the GP may refer for more detailed neuropsychological assessment, brain imaging, or a memory clinic consultation.

The Australian context for the workup is laid out in three current sources. The Clinical Practice Guidelines and Principles of Care for People with Dementia (Guideline Adaptation Committee, 2016) remain the formally current Australian dementia clinical practice guidelines, with an updated version due from Monash University in mid-2026. They are complemented by the Australian Government's National Dementia Action Plan 2024–2034 (Department of Health and Aged Care, 2024) and by the Dementia in Australia compendium maintained by the Australian Institute of Health and Welfare (AIHW, 2025), which together describe the current Australian framework for dementia diagnosis, care, and prevalence.

The point worth carrying out of this section is that the workup is not a binary diagnostic test. It is a careful look at the whole picture, and it usually arrives at a reasonably clear conclusion about which of the three categories the person is in, and what kind of follow-up makes sense.

A note on what reading this guide cannot do

This guide does not assess your memory, and it cannot tell you whether you have a problem. The same is true of any online self-test or symptom checklist. The decisions that matter, including whether anything needs to be done, belong with a clinician who can take a history, examine the picture as a whole, and refer for further assessment if it is warranted. If the worry has been with you, or with someone you love, for more than a few weeks, the right move is not more reading. It is a conversation with a GP.

From one question to several

What the differential does is replace a single, terrifying question, "is this dementia?", with a more useful set of questions: what kind of forgetting is this, what causes it, what treatable conditions might be in the picture, and what next step does the answer point to? These are questions a clinician can help with. They are not questions the person should be sitting with alone.

Most cognitive worry in later life turns out to be normal age-related change, or to have a treatable cause that is not dementia. Some of it turns out to be MCI, which warrants follow-up but is not a prediction. Some of it turns out to be early dementia, in which case the support available is more substantial than it used to be, and the value of an early diagnosis is well-established. None of these outcomes is improved by waiting in silence. All of them are improved by bringing the worry into the consulting room.

This content is general information only. It is not a substitute for individual psychological or medical advice. Reading this does not establish a therapeutic relationship with Equal Psychology or any of their clinicians.