There could be some "dark city" inspiration right there, don't know if you have seen the movie. If you didn't, take a look at it, it's pretty good.
SPOILER ALERT (Well, kind of, the story unfolds in 10 minutes and there are many other things happening) :
Basically, a bunch of creepy aliens perform experiments on a city, every hour, every citizen fall asleep and the aliens inject new memories into them. The carpenter becomes a rich business man, the hooker becomes a married woman, the nice guy becomes a killer etc. They also change the city, according to the new memories, and they watch, trying to understand what's the soul, because they need one to survive. They believe that the solution lies within our memories, inside our brains.
Then comes a guy who basically tells them "Yo, soul is not in the brain, you dumby dumb aliens!"
END OF SPOILER ALERT
The thing is, maybe the idea is to show that what makes you "human" (your soul, if you will) is not your brain. The conversation with your brain highlights that, since he says that he constantly tries to warn you against dangers, he doesn't agree with your life choices, he even judges you harshly. Your freedom of choice is independent from your organs. The brains of Big Mt. didn't understand that it takes more than keeping the brain alive to keep living, with what keeps you moving forward.
If we really want to give Old World Blues an artistic thematic. Can also be a fun, mindless but successful DLC.