Activating Cells in the Brain - What We Learned

There's an organ specific end gram or compartment specific end gram. I'm not quite sure which one it is, like inside the colon versus in the abdomen of space. And there has to be something that's happening to those subset of cells. But this point is an interesting one because the whole field of optogenetics and these chemical genetic approaches to activate cells in the brain kind of revolutionize neuroscience in one way,. Because now you've got these causal experiments.