Now, a new study is sharing one way that changes in your eye health may help predict future cognitive decline. It says that one particular change, which your doctor may notice during an eye exam, could serve as a “noninvasive ocular biomarker” for future dementia. Read on to learn which change with your eyes could help predict dementia, and which other eye conditions are linked to your cognitive health. READ THIS NEXT: If This Has Happened to You, Your Dementia Risk Soars, Experts Warn. Alzheimer’s disease (AD)—a neurodegenerative disease caused by an abnormal build-up of amyloid and tau proteins in the brain—is the most common cause of dementia in older adults. Alzheimer’s symptoms often include memory loss, difficulty thinking, behavioral and mood changes, and more. On top of these common symptoms, people with Alzheimer’s may also experience changes in their vision, such as poor peripheral vision, difficulty with object recognition, poor color discrimination, and lowered depth perception. This link has prompted researchers to explore the connection between eye health and dementia. “The relationship between brain tissue and eye tissue is an area of intense interest for ophthalmologists and neurologists,” says the American Academy of Ophthalmology. “Research shows that diseases and conditions of the brain can also affect the eyes because the optic nerve and retina are actually brain tissue that extends outside the brain case. Alzheimer’s disease and dementia, which are caused by damage to brain cells, both appear to have effects on the retina.” READ THIS NEXT: Taking These Medications for Even a Short Time Spikes Your Dementia Risk. According to a 2022 study published in the journal JAMA Ophthalmology, one particular eye change could offer a clue about your future dementia risk. The study, which took place in South Korea, examined the connection between retinal layer thickness and future cognitive decline in a cohort of 430 individuals over the age of 60. They concluded that macular retinal nerve fiber layer (RNFL) thickness is associated with future cognitive decline in seniors.ae0fcc31ae342fd3a1346ebb1f342fcb “We propose that a thinner macular RNFL may predict a decline in cognitive performance,” the study says. “Overall, macular RNFL thickness may be considered a noninvasive ocular biomarker for assessing changes in cognitive function in patients.” The study authors observed a correlation between the extent of cognitive decline and the degree of macular RNFL thinning. “A greater decline in cognitive scores and a higher prevalence of cognitive impairment and Alzheimer disease was seen for participants with baseline total macular RNFL thickness below the lowest quartile cutoff value versus those with RNFL thickness above the lowest quartile cutoff value,” they wrote. While these changes are likely to go unnoticed by the person experiencing them, an eye specialist can see these changes during an eye exam. For more health news sent directly to your inbox, sign up for our daily newsletter. Several other studies have worked to shed light on the connections between ocular health and brain health. So far, the evidence suggests that people with macular degeneration, glaucoma, and diabetic retinopathy are at a significantly increased risk of developing dementia down the road. In fact, a 2018 study from the University of Washington and the Kaiser Permanente Washington Health Institute found that subjects who had one or more of these eye conditions were at a 40 to 50 percent greater risk of Alzheimer’s disease, compared with others who did not. While not everyone with these eye problems will go on to develop a neurodegenerative condition, the findings underscore the importance of eye exams, which the American Academy of Ophthalmology recommends for everyone beginning at age 40. Speak with your doctor or ophthalmologist if you notice changes in your vision, or if you have questions about how your eye health may clue you in to other aspects of your general health. READ THIS NEXT: Skipping This Step in the Bathroom Increases Your Dementia Risk.