Lee explained further: “Previously, the working hypothesis most attributed the damage observed in Alzheimer’s disease to what came after amyloid build-up outside of brain cells, not before and from within neurons.”
The theory Alzheimer’s is caused amyloid-beta has been the dominant hypothesis since the late-20th Century; however, it has never been universally accepted by researchers.
Neurobiologist Ralph Nixon said of the research: “This new evidence changes our fundamental understanding of how Alzheimer’s disease progresses.
“It also explains why so many experimental therapies designed to remove amyloid plaques have failed to stop disease progression because the brain cells are already crippled before the plaques fully form outside the cell”