I can pause. I don't have to immediately come up with something. If I'm sitting across the table from someone, I have to say something, because if I look at something else, it looks like I'm bored (this was drilled into my head as a child, with the result that I'm super-conscious of it), and if I stare at them and not say anything, it's weird.

Solution: seems to me that when meeting someone one-on-one, a seating arrangement where looking straight ahead does not require looking at the other person would help me come up with words. So... maybe bar or couch-style seating vs. across the table seating.