How much detail should I add in SOP about fit with particular labs/professors?

[warm-valley]

To add some detail, I'm interested in neurodevelopmental and mood/anxiety disorders, particulary in researching what are the differences in the brains of these populations vs typical brains, and how these differences impact motivated behaviours and decision making.

The particular project I do would somewhat depend on the methodologies/focus of the lab I end up joining. Should I write about how the work in each lab would help me research my interests? Should I also give examples of questions I could research for each of them, or would this make me look too scattered, since it would look like I don't have a clear project in mind?

For context, I'm applying to programmes in the US.