I tend to explore and put myself in challenging contexts. So my experience ranges from "not much to contribute / am dumber" (mostly public intellectualism insecurities, new creative areas) to "not much to contribute / am smarter" (gossip, incompetent work env., bullying)
I mean, I don't WORRY about it, but I have the depth of a kiddie pool so I obviously bring nothing to the table. But it's not like I'm fretting over it. I just listen instead.