Pupil Dilation Speed Could Indicate Alzheimer’s Risk

Credit: narcononnewliferetreat.org

A new study published earlier this month concludes that pupil dilation speed could be an indicator for individuals at risk of developing Alzheimer’s disease.

It’s becoming clearer and clearer that early detection of Alzheimer’s disease is imperative. Alzheimer’s is not yet curable. However early detection is vital to slow its progression. And slowing its progression is entirely possible, which can add many years to a person’s non-cognitively impaired life.

Researchers out of the University of California San Diego School of Medicine conducted the study. (It was published online in the September 9 issue of Neurobiology of Aging.) They say that pupil dilation speed during cognitive tests could be a low-cost, low-invasive method to determine if an individual is genetically at risk of developing Alzheimer’s disease later in life.

The study focuses on pupil response, which is dictated by the locus coeruleus part of the brain. The locus coeruleus is a bunch of neurons in the brainstem that regulates general arousal and cognitive function. Accumulation of tau proteins is a well-known biomarker for Alzheimer’s disease, and tau first appears in the locus coeruleus. According to the study, pupil dilation response during a cognitive test is therefore indicative of locus coeruleus functionality.

Pupils enlarge whenever the brain is given a difficult cognitive test. The same research team has previously published work regarding pupil dilation in patients with mild cognitive impairment. MCI often is a precursor to Alzheimer’s disease, though not all cases of MCI develop into Alzheimer’s. The previous study reported greater pupil dilation and “cognitive effort” in people with MCI compared to people with normal cognitive function.

William S. Kremen, Ph.D., professor of psychiatry and co-director of the Center for Behavior Genetics of Aging at UCSD School of Medicine, was the lead author of the study.

“Given the evidence linking pupillary responses, LC and tau and the association between pupillary response and AD polygenic risk scores [an aggregate accounting of factors to determine an individual’s inherited AD risk[]” said Kremen, “these results are proof-of-concept that measuring pupillary response during cognitive tasks could be another screening tool to detect Alzheimer’s before symptoms appear.”

A New Method for Early Detection

Early detection of Alzheimer’s warning signs is imperative. It seems that every week there are studies regarding novel methods for determining who is at risk or in early stages of Alzheimer’s disease. It’s also clear that our population is the oldest it’s ever been, and that all forms of dementia will be on the rise.

It’s encouraging to know that scientists and researchers are doing everything they can to determine new criteria for the disease. Early recognition of those at risk or already in the early stages of dementia is the best option for slowing the disease progression we have today.