caduceus
It's not really neurological, but you people are so smart you probably know general historical things we clinicians don't, so here goes: A bunch of the lads were sitting around the on-call room wondering how Mercury's double-snaked caduceus got connected with Medicine. Didn't Aesculapius have a staff with only one snake? One of the guys wanted to blame it on the U.S. military, but he always does that. And for bonus points, what do snakes have to do with anything, anyway?