Most of my musculoskeletal stuff was directly attributable to carrying 100+ lbs of kit up and down the street, up and down stairs, and over 2-meter walls, 4-12 hours a day.
Maybe there's no correlation and it was just a placebo-type thing and/or my mind playing tricks on me, but I'm inclined to think that the improvement in longstanding tissue-related issues that were caused by deploying also ameliorated some of the psychological residue of that experience.
http://en.wikipedia.org/wiki/Body_memory
Come on.
It's not like it's impossible to be taught BS (e.g. that "something us incorrect") and it later to be proven true after all...
For my money, I'd question whether it's worth comparing an organism that can regenerate it's brain against any vertebrate that cannot.