In particular, how much do we know about how human brains learn?
I'm also particularly interested in details at a level similar to this post:
What I remember about this is vague, but my understanding is that we don't (or didn't until very recently) have particularly strong evidence about how (human) brains do the equivalent of reinforcement learning in { decision theory / statistics / AI / ML }.
Do we know significantly more now versus five (5) years ago? What do we know now (and how do we know it)?