Diarrhea of the Mouth

This phrase is totally disgusting, and yet it describes some things so perfectly well that I must use it.
For example, after school, I go to the sitter's and pick up Little Man. After watching him play with the other little boys for a minute, and talking to the sitter to see how his day went, we load up in the car for the ten minute trip home. Usually, I try to interact with him about what he sees, or who's house he was at, or what color the truck was that drove by, those kinds of things.
Yesterday, I didn't feel like talking because I had a headache. But, Little Man didn't see the need in being quiet. He talked and talked and talked.
About what?
I have no clue!
He went from red trucks, to Blake's truck, to Blake's sleeping, to making snoring sounds, to making cow, pig, chicken, duck and horse sounds. From there he talked about seeing horses and cows, and then colors that he knows, and then something about Daddy, and then he named every person he knows, and then he just started screaming, all because that's what came to his head.
It reminded me of being in college, and those English teachers that told us to just write down whatever was in our heads, whether it made sense or not. Stream of conscienceness exercise or something like that. Funny. My child is almost two and doing the things we did in college. I don't know whether to be impressed by my child, or depressed that in college that was a hard thing for me to do.