Can you talk about that? And are we witnessing something that is very different in how we think about neurodegeneration?

Yeah, that's exactly right.

And that's a great place to start because you're right.

Historically, if we go back even to some of the earliest writings about Alzheimer's disease, you know, a hundred years or so ago, they were describing vascular changes in Alzheimer's disease, but it was kind of set to the side because the thing that jumps out to you when you look at pathology in an Alzheimer's disease brain is amyloid beta plaques and tau-containing neuroferbular retangles.

And, you know, there's been a lot of work over the years looking at vascular function and how it changes in disease.

So there have been some really excellent longitudinal studies where people have looked at cohorts of 5,000 individuals and track them over up to seven years or more.

And they can see that cerebral perfusion changes.

How did that, did I get that right? And then how did that lead to the Alzheimer's kind of focus?