A pair of reading glasses on a table in front of an eye test chart

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How your vision can predict dementia 12 years before it is diagnosed – new study

The eyes can reveal a lot about the health of our brain. Indeed, problems with the eyes can be one of the earliest signs of cognitive decline. Our latest study shows that a loss of visual sensitivity can predict dementia 12 years before it is diagnosed.

Our research was based on 8,623 healthy people in Norfolk, England, who were followed up for many years. By the end of the study, 537 participants had developed dementia, so we could see what factors might have preceded this diagnosis.

At the start of the study, we asked participants to take a visual sensitivity test. For the test, they had to press a button as soon as they saw a triangle forming in a field of moving dots. People who would develop dementia were much slower to see this triangle on the screen than people who would remain without dementia.

So why might that be?

Visual issues may be an early indicator of cognitive decline as the toxic amyloid plaques associated with Alzheimer’s disease may first affect areas of the brain associated with vision, with parts of the brain associated with memory becoming damaged as the disease progresses. So vision tests may find deficits before memory tests do.

There are several other aspects of visual processing that are affected in Alzheimer’s disease, such as the ability to see outlines of objects (contrast sensitivity) and to discern between certain colours (the ability to see the blue-green spectrum is affected early in dementia), and these can affect people’s lives without them being immediately aware it.

Another early sign of Alzheimer’s is a deficit in the “inhibitory control” of eye movements, where distracting stimuli seem to hold attention more readily. People with Alzheimer’s seem to have an issue ignoring distracting stimuli, which may show up as eye-movement-control issues.

If dementia makes it harder to avoid distracting stimuli, then these problems could increase the risk of driving accidents – something we are currently investigating at Loughborough University.


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For the full article by Professor Eef Hogervorst, Dr Thom Wilcockson, and Ahmet Begde visit the Conversation.

Notes for editors

Press release reference number: 24/49

Loughborough is one of the country’s leading universities, with an international reputation for research that matters, excellence in teaching, strong links with industry, and unrivalled achievement in sport and its underpinning academic disciplines. 

It has been awarded five stars in the independent QS Stars university rating scheme and named the best university in the world for sports-related subjects in the 2023 QS World University Rankings – the seventh year running. 

Loughborough is ranked 7th in The UK Complete University Guide 2024, 10th in the Guardian University League Table 2024 and 10th in the Times and Sunday Times Good University Guide 2024. 

Loughborough is consistently ranked in the top twenty of UK universities in the Times Higher Education’s ‘table of tables’, and in the Research Excellence Framework (REF) 2021 over 90% of its research was rated as ‘world-leading’ or ‘internationally-excellent’. In recognition of its contribution to the sector, Loughborough has been awarded seven Queen's Anniversary Prizes. 

The Loughborough University London campus is based on the Queen Elizabeth Olympic Park and offers postgraduate and executive-level education, as well as research and enterprise opportunities. It is home to influential thought leaders, pioneering researchers and creative innovators who provide students with the highest quality of teaching and the very latest in modern thinking.