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Brain check

Three short tests, measured against your own first result.

Not a dementia test. These measure speed, span and attention on your own device. One result means nothing; a line over months means something.

What actually moves these

Ranked by how much the evidence says each one matters, not by how easy it is to sell.

1Sleep

The largest single influence on reaction time, and the one people discount. One bad night is worth roughly the same slowing as a modest amount of alcohol.

2Blood pressure

Pressure treated in midlife is one of the few things with trial evidence behind it for later thinking.

3Hearing

Untreated hearing loss is the single largest modifiable dementia risk factor in the Lancet Commission list, and correcting it is straightforward.

4Movement

Aerobic exercise has the best evidence of anything you can do deliberately, and the dose is ordinary rather than heroic.

5Alcohol

Reliably slows all three of these the next day, in amounts most people would not call heavy.

When a change is worth an appointment

Not a slow week. The pattern doctors listen for is different in kind: the same question asked twice in one conversation, a recent event gone rather than delayed, a familiar route becoming confusing, or new trouble with money, medicines or appliances that were routine a year ago. Family usually notice before the person does, and that asymmetry is itself the signal.

Normal forgetting, and the kind that is notBrain health, honestlyIf you are caring for someone

Common questions

Is this a dementia test?
No, and nothing on this page can be. Dementia is diagnosed by a clinician using a structured assessment, a history from someone who knows you, blood tests for the treatable imitators, and sometimes a scan. These are three brief measures of speed, span and attention. They are useful because they are yours and repeated, not because any single result means anything.
Which of the three brain tests should I do first?
Reaction time, because it takes under a minute and is the least affected by how hard you try. Do memory second, since it is the one that changes most with sleep, and focus last, because it is tiring and will drag the other two down if you run it first. All three together take about three minutes, and doing them in the same order each time is what makes the comparison worth anything.
I did badly today. Should I worry?
Almost certainly not. A poor night of sleep, a drink the evening before, a cold coming on, a stressful morning, some medicines, and simply the time of day all move these numbers more than most people expect. One result is noise. A clear, sustained change across months, especially one other people have also noticed, is the thing that deserves an appointment.
How often should I do them?
Three runs in the first week to settle a baseline, because everyone improves at the task itself before they settle. After that, once a month is plenty. More often and you are measuring your mood.
Do the results leave my device?
Only if you sign in and save them, and then only into your own record, which is private to you. Signed out, they stay on your device and nothing is uploaded.
Do brain training apps work?
They make you better at the app. The fair trials have not shown that improvement transferring to everyday memory or thinking, which is what people are buying it for. The things with real evidence are on this page and none of them are games: sleep, blood pressure, hearing, movement, alcohol and staying socially connected.

Also in this section

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Health education, not medical advice. Sudden confusion over hours or days is not this: that is delirium, and it needs a doctor the same day. Anything urgent, including chest pain or trouble breathing, needs your local emergency service, not this form.