I won't say “more”, I certainly can't blame him to have difficulty to learn!
I don't want to know what it feel to be him but I wonder how his perception turned after that. They say the right side of the brain is used most for the “inner” activity and the artistic side (or was it the left side? nm).
Sometimes, people who suffer of epilepsy see their brain connection cut in half in surgery. The brain is separated in two sides, they cut the connection in the middle. Both sides can't respond anymore to the data of the other, there's no more short circuit and the electrical storm end. The only bad part, some patients see one of their hand becoming uncontrolable occasionnaly.
In short, I think he survived because the deep center of his brain wasn't touched. That center contain also the biological clock, among other things. I often think that the whole brain, in addition to making some functions, protect that center.