And if we could travel back to a few decades ago, what did researchers know and why were animal models considered important for the study of Parkinson's? So Jeff, maybe you can go first.

So there are a number of reasons why we need animal models.

First is if we're going to develop new therapies, we need to make sure that they're safe and effective and well tolerated.

And we can do those studies in animal models.

What we initially thought was that Parkinson's disease was just a dopamine disease, a nigrostriatal degeneration disease.

And so the models that were developed were six hydroxy dopamine lesions in rodents.

And eventually, once the discovery of MPTP in non-human primates, MPTP became the model.

So how should we think about what is the best model? Which model should the field use? Is there even such a thing? Should the field use one model or should the field use multiple models?