Egyptians thought that the heart was your brain. They were, uh, wrong. Even today though, it's a prettier sentiment. Consider: "You have my braiiiiin." Not romantic, unless you're boning a zombie.
But this is the ugly, wrinkly, squishy, neuro-chemical-flooded, color-coded truth. Hopefully this is what your brain looks like today! If not, I'm sorry you're going to die alone, 'cause that's what happens to single people on Valentine's Day, or at least that's what I read on the internet. Click to embiggen. [Scientific American via The Hairpin]
P.S. Every time I think about brains, I flash black to that scene in Robocop 2 when Robocop smashes that drug-dealer-turned-giant-mecha's brains into concrete and really grinds his elbow in there good, to crush all the tiny brain-y bits, like jelly. Is that a normal? I saw that movie when I was like 6 and I'm worried it scarred me for life or something and I'm only going to think about that when I think about love from now on. Thanks, science. And Robocop.