STAT+: Scientists find a clue to why some people have ‘Alzheimer’s brains’ but no dementia
Defective proteins clump into toxic plaques and tangles. Plaques of amyloid and tau tangles kill neurons, causing Alzheimer’s disease. So goes the central dogma that has ruled neuroscience since the early ’90s.
But in the last few years, as researchers have amassed large databases of brain scans and collections of donated tissue, it’s become apparent how frequently the conventional wisdom fails. By one recent estimate, about 30% of older adults have brains loaded with enough amyloid or tau to meet the criteria for an Alzheimer’s diagnosis, but no outward symptoms of dementia.
