Loss of Visual Sensitivity Can Predict Dementia Disease- Study

Visual issues today have a lot to say about the chances of getting dementia because the brain's health could be seen through the windows of the eyes, according to a study.

Problems with vision often surface as one of the earliest indicators of cognitive decline. 

Recent research shows that a loss of visual sensitivity can predict dementia up to 12 years before a formal diagnosis.

Researchers conducted a study involving 8,623 healthy individuals in Norfolk, England, monitored over several years. 

By the end of the study, 537 participants had developed dementia, allowing researchers to identify potential early indicators of the disease.

According to the study, your eye can predict dementia in advance 12 years apart.

At the beginning of the study, participants underwent a visual sensitivity test, where they pressed a button upon seeing a triangle in a field of moving dots.

The Science Alert posited that adults individuals who later developed dementia were significantly slower in detecting the triangle than those who did not develop the condition.

"Visual issues may serve as an early sign of cognitive decline due to the toxic amyloid plaques associated with Alzheimer's disease, which initially affect brain areas related to vision.

"As the disease progresses, it damages regions associated with memory, suggesting that vision tests might detect deficits earlier than memory tests," the Research revealed.

Some of the defect association with Dementia may include:
Alzheimer's disease
Alzheimer's disease affects several aspects of visual processing, such as contrast sensitivity (the ability to see object outlines) and color discernment, particularly in the blue-green spectrum. These deficits can impact daily life without immediate awareness.
Inhibitory Control and Eye Movements

Another early sign of Alzheimer's is impaired "inhibitory control" of eye movements, where distracting stimuli capture attention more readily. Individuals with Alzheimer's struggle to ignore distractions, leading to eye-movement control issues. This difficulty can increase the risk of driving accidents, a subject currently under investigation at Loughborough University.

Faces Recognition: A Cognitive Challenge
Evidence suggests that people with dementia process new faces inefficiently, not following the usual eye movement pattern from eyes to nose to mouth. This inefficient scanning makes it harder to imprint and remember faces, leading to recognition difficulties.

Healthcare professionals often notice this when interacting with dementia patients, who may seem lost due to ineffective environmental scanning.

Improving Memory Through Eye Movements
Given the link between visual sensitivity and memory performance, researchers are exploring whether encouraging eye movements can enhance memory.

While previous research shows mixed results, some studies indicate that eye movement can boost memory. This could explain why those who watch TV and read more have better memory and a lower risk of dementia.

Educational Impact on Memory and Dementia Risk
Reading frequently often correlates with higher education levels, which builds brain reserve capacity. This reserve helps mitigate the negative effects of brain damage. Additionally, quick left-to-right and right-to-left eye movements have been found to improve autobiographical memory, though this benefit appears more pronounced in right-handed individuals for reasons not yet understood.

Eye Movements in Memory Treatment
Despite promising findings, using deliberate eye movements as a treatment for memory issues in older adults is still not widespread. Eye movement deficits are not regularly used as a diagnostic tool, partly due to the high cost and complexity of eye-tracking technologies.

Until these technologies become more affordable and user-friendly, using eye movements for early-stage Alzheimer's diagnosis remains limited to laboratory settings.

Early detection of dementia through eye health assessment holds significant potential. With advancements in eye-tracking technology, these diagnostic methods could become more accessible, offering a non-invasive way to identify and address cognitive decline early.