Eye movements and brain activity may be the key to diagnosing Alzheimer's disease earlier and more accurately, according to research led by Chilean neurologists. Roselle Chen reports.
Chilean neurologists say they've found a key to diagnosing Alzheimer's disease early, even before memory loss and other symptoms develop. Researchers at Chile's Biomedical Neuroscience Institute (BNI) believe they can identify early stages of dementia and other psychiatric diseases in sufferers through observing eye movement patterns and the brain's electrical activity. The neurologists study patients navigating a virtual location, where they must find "keys" to complete a task. Lead neurologist Enzo Brunetti said the tests were able to detect very early signs of cognitive impairment in patients who apparently presented no symptoms of Alzheimer's. (SOUNDBITE) (Spanish) NEUROLOGIST AND RESEARCHER, ENZO BRUNETTI, SAYING: "In this study, what we did was that we applied spatial navigation tasks using a computer, and with the help of a software we examined in detail which were the early functions that became altered in Alzheimer's disease (patients) and focused on a very specific function, linked to the codification and development of cognitive memory, that helps people move through the physical environment. This is one of the cognitive functions that were altered in patients with Alzheimer's and we observed that they were altered from very early stages. Therefore we believe this is a biomarker for the disease, which would give us an opportunity to shed light on an early diagnosis for this disease." Brunetti says the patients who are likely to develop some form of dementia make similar eye movements while navigating through the virtual "room" to those at a developed stage of the disease. With the help of electrodes that measure the brain's electrical activity, the neurologists run non-invasive electroencephalogram (EEG) tests on patients while they navigate through the computer-made universe. More tests and a larger clinical trial are needed before the treatment can be made available. An early Alzheimer's diagnosis may not only help patients and their families plan better for the future, but also offer them a possibility of delaying the symptoms with drugs and other existing treatments. Alzheimer's is very difficult to detect until it has progressed from mild memory loss to clear impairment. Patients eventually lose all ability to care for themselves.