Researchers have found that a simple eye test can predict Alzheimer’s disease up to 12 years before diagnosis. The study, which involved 8,623 adults, tested participants’ ability to detect a faint triangle on a computer screen. Those who later developed dementia required roughly two extra seconds to spot the triangle, raising their risk by 56 percent.
The test measures visual processing speed and is related to memory performance, according to lead author Eef Hogervorst. The study also found that people with Alzheimer’s often struggle with visual sensitivity, contrast sensitivity, color discrimination, and motion detection.
The retina is an outgrowth of the brain, so toxic proteins can accumulate there first, leading to damage in the occipital cortex before spreading to the hippocampus. This makes eye-based tests a potential warning window for preventive care.
Researchers are now exploring retinal layers for thinning, abnormal blood vessels, and microscopic deposits that mirror cerebral changes. Damage often begins in the occipital cortex before spreading to the hippocampus.
While technology alone is not enough, lifestyle factors such as reading, exercise, and healthy vision habits can also help prevent cognitive decline. Optometrists recommend annual exams after age 60, and reporting new glare or slowed adaptation can nudge physicians to order broader cognitive checks.
The study’s findings have been published in Scientific Reports, providing new hope for early detection and prevention of Alzheimer’s disease.
Source: https://www.earth.com/news/your-eyes-vision-could-alert-you-to-dementia-alzheimers-disease-up-to-12-years-earlier