An updated version of an established brain test does an excellent job diagnosing early Alzheimer's disease, new research shows.

Electroencephalograms (EEGs) have been around for 80 years. In tests on 71 patients, a team of scientists determined that a modified EEG spots Alzheimer's with as much as 85-percent accuracy-almost as good as the 90-percent accuracy of the most sophisticated modern tests at major medical centers. Better yet, the EEG is available almost everywhere.

"State-of-the-art evaluation for Alzheimer's disease is available only to those who have geographic proximity and/or financial ability to access research hospitals, where expert neuropsychologists continually interview patients and caregivers over six to twelve months to make a diagnosis," says principal investigator Robi Polikar, PhD, of Rowan University in New Jersey. "But most people don't have access to such facilities, and instead they go to community clinics and hospitals," where an EEG is readily available.

An EEG also can be done in a doctor's office. It is noninvasive and safe to administer repeatedly, so it's an "ideal method to screen elderly individuals for the earliest indication of this common scourge of late life," says another member of the research team, Christopher Clark, MD, a board-certified neurologist and associate director of the Alzheimer's Disease Center at the University of Pennsylvania.

Other teams, meanwhile, are seeking to create a formula—or algorithm—that will predict the likelihood for developing Alzheimer's based on such criteria as age, cognitive function and physical ability; isolate an Alzheimer's-identifying gene sequence; and apply "pattern recognition software" to a combination of imaging techniques in order to differentiate between people with mild cognitive impairment, which often precedes Alzheimer's, and those with the disease itself.