No. In fact, you can damage parts of your brain and it would have no or very minor effect on you. It really depends on which area you damage, some affect memory, others sight, yet others personality. There was an interesting story in my psych book about a guy who had a similar accident to a kid in this article. A pole went through his brain, and the guy was fine except that...his personality changed. He became like a different person.
What, didn't like EaW? I haven't played the game extensively nor have I passed the campaigns, but from what I've played it was a great game! The battles seemed pretty fast and interesting and the galactic view was a nice idea.