|Neurotrack develop visual test to identify Alzheimer's|
before symptoms appear. (Image source)
Worldwide nearly 44 million people have Alzheimer’s, and the disease is most prevalent in Western Europe and North America. The cost of caring for Alzheimer’s patients in the U.S. is estimated to be $226 billion in 2015, and the global cost of the disease is estimated to be $605 billion, equivalent to 1% of the entire world’s gross domestic product.
Researchers believe that early detection is key to preventing and stopping Alzheimer’s disease. Diagnosis is usually performed by primary care physicians through a clinical interview and family history. Neurological examinations and cognitive tests can help make the diagnosis, as well as spinal fluid analyses and PET scan to detect the buildup of amyloid-beta proteins in the brain. But spinal taps are cumbersome and PET costs $3,000 per scan, and by the time symptoms are present, studies have shown that the disease may have been active for up to 20 years.
Neurotrack, a California-based startup, is developing a noninvasive, fast and cheap computerized visual test to accurately identify people at risk of Alzheimer’s. The technology is based on research by Stuart Zola, the co-founder of Neurotrack, who studies learning and memory in monkeys. When presented with two images, one novel and the other familiar, primates will fixate longer on the novel one. If the hippocampus is damaged, as in Alzheimer’s, the subject spends equal time looking at each image.
In a five-year study, investigators gave a half-hour test to 92 seniors, both cognitively normal and with mild impairment. They were able to predict, three years in advance, who in the normal group would become impaired and which of the mildly impaired would later develop Alzheimer’s. Based on these findings, the company developed a five-minute web-based version that uses basic webcams to capture eye movement. The test could become an affordable tool for widespread screening, enabling doctors to identify people at risk for Alzheimer's up to six years before symptoms emerge.
The 5-minute test is currently in multiple studies, where its results are compared with blood tests, cognitive exams, and evaluated alongside PET.