Do you recognize users by username or by avatar?

I tend to remember avatars more than I do usernames. Of course, some usernames are easy to remember so even when they change their "faces" (@darthorange and @animasta, I'm looking at you) I still "know" who they are. But as for the rest of the world, if your image changes you become a new user entirely to me.

How about you? Does it throw you when an oft-seen name is no longer attached to a discarded avatar? Or do you recognize strings of characters better? Or are you a terrifying mnemonist.