Amyloid forms plaques between brain cells; tau forms tangles inside them. Both begin building up years before symptoms, which is why diagnosis is moving earlier.
Blood tests for these markers are emerging but their role in routine practice is still being established.
Why it matters
These tests decide eligibility for the newest drugs, which is why a family may be offered one.
Sources
Where to check this, and where to read more. All external and all authoritative.
- National Institute on Aging: What happens to the brain in Alzheimer's
- Alzheimer's Association: Medical tests for diagnosis