Is it possible for someone who has always been a right-brained person (english, history, music art, etc.) to become a left-brainer (science, math, logic, etc.) or are you stuck how you are? Can you retrain yourself?

there was a fascinating case of a guy, who was very good at mathmatical type things, who suffered serious damage to that side of the brain. He survived with all his faculties intact, but suddenly developed a strong artistic streak, and started producing some amazing sculptures - dark brooding prancing horses and the like. I think he also lost interest in science-y stuff as well, sorry I can't remember any specifics.

Also, doesn't quite answer your question! My personal view is that yes you could retrain, but it would be incredibly hard, in that the dominant side really does dominate and subjugate the other side. It would be a question of releasing control I believe, of disregarding things that you previously took as important. e.g. a scientific person would attach a lot of importance to a kind of quantifiable and definite judgement of situations, wheras an artistic person would be more likely to attach importance to more vague and subjective assessments of a situation.