Hard to say whether I mean specific situations or just in general. When I'm picked up from somewhere, if I walk towards someone I know, or if I want to say something to someone, I always get this huge smile on my face that I can't do anything about it.
Now that I've thought about it some more, this happens immideately after I've dismissed all of my internal thoughts and have no pressing things to think about, and I do this zeroing out every time I'm with a person I'd like to interact with.
This could just be an introverted vs extroverted thing. When I'm alone, I think introverted stuff, when I interact with other people, I think of extroverted stuff. If I interact and haven't been able to get rid of my introverted thoughts because there's something I need to do with them, I won't start smiling simply because of the interaction itself.
Haa, this post is a mess, but I don't have time to fix it and I probably wouldn't type it again if I redid this later on.