A study published earlier this year revealed a groundbreaking observation that could be key in identifying dementia years earlier than is currently thought to be possible.
Researchers studied 8,623 people over ‘many years’ and by the end of the study, 537 of the participants had developed dementia.
At the start of the study, participants were asked to take a visual sensitivity test. During this test, they had to press a button as soon as they saw a triangle forming in a field of moving dots.
Those who had gone on to be diagnosed with dementia were much slower to see the triangle on the screen than those who were not diagnosed with the condition.
What can our eyes tell us about our future risk of dementia?
According to the researchers: “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.”
Additionally, the ability to see outlines of objects and to discern certain colours are aspects of visual processing that are affected in Alzheimer’s disease.
The researchers added that another early sign is a deficit in the “inhibitory control” of eye movements, where distracting stimuli seem to hold attention more readily.
Researchers said: “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.”
What does this mean for the future of dementia diagnosis?
Unfortunately, nothing for now.
Researchers admitted that a bottleneck for them currently is access to eye-tracking technologies that are both expensive and complex to learn. They added: “Until cheaper and easy-to-use eye trackers are available, using eye movements as a diagnostic tool for early-stage Alzheimer’s is not possible outside the laboratory.”
Let’s hope that as Alzheimer’s research gains more interest and funding, we will soon be able to utilise this information on more patients.