Science has found that long before the onset of Alzheimer's symptoms, the brain already has two defining elements of the disease: the formation of neurofibrillary clusters of the Tau protein, which are a kind of tangle that prevents communication between neurons, and the accumulation of plaques, which is considered an unequivocal sign of the disease. Researchers at the University of Pittsburgh School of Medicine in the United States have focused their efforts on the first of these events and have developed a test based on these Tau clusters to anticipate the diagnosis of Alzheimer's by approximately a decade.