This is the context:
This is a difficult issue, to ask about animal subjective experience. For many animals, we can’t be with them without thinking they have subjective experience. To those of you who have a pet dog, I bet you implicitly assume that the dog has a deep and rich subjective experience, even though you just don’t know. Even if we ignore the subjective experience question and ask, What are animals thinking?—which I believe we have better measures to gain some traction on—it is still puzzling.
source: The enigma of human consciousness.New York Academy of Sciences.
What is the meaning of "gain traction on" in this context? I've looked and there were two definitions that looked suitable. one is
1a: things are starting to happen towards whatever the goal is.
2b: advancement, as toward a desired result.
the extent to which an idea, product, etc. gains popularity or acceptance.
which one is correct in this context? or if none of them is correct, what is the correct meaning?