Shrinkwrapped's post on sociopathy is a good update, and raises intriguing, age-old questions about free will and responsibility which go far beyond the topic of sociopathy. The Greeks understood these things better than we do. Fate, personality temperaments, and all that.
Everybody's brain seeks excuses for their body's wrong or irresponsible behavior: My Brain Made Me Do it.
I might revise the title to "My brain made me blame my brain." That's the one I use when I screw up.
I have no answers to these conundrums (conundra?).