This discussion about the cause of Alzheimer's is not new, it has been going on for something like 10-15 years at least. What is triggering the publicity now is

This discussion about the cause of Alzheimer's is not new, it has been going on for something like 10-15 years at least. What is triggering the publicity now is that two drugs targeting amyloid failed to produce real improvement even though they were effective at reducing amyloid. Especially the newer one produced very large and measurable reduction of amyloid, but only very small (but measurable) cognitive improvement. In any case the whole amyloid system is involved somehow, I think that much is very likely. Just not in the way that the visible amyloid fibers are the cause, but might just be another symptom. This is not anything like heretical talk, this suspicion was pretty much mainstream when I studied biochemistry ~15 years ago. It was only a hypothesis, but it certainly wasn't suppressed.