The left hemisphere is usually associated with the more logic based functions, where as the right is more emotionally based responses. With the corpus collosum intact, both hemispheres will communicate and the dominant hemisphere will decide your actions by inhibiting the other. Sometimes in normal people the more submissive side (often the right side) will ignore that relationship and just momentarily act in a way you may not normally. This alien hand is just a result of the bridge being severed (corpus callosum) and the dominant hemisphere can't inhibit these movements
This video explains the lateralization of function a little more clearly. Its a little long, but you'll learn a lot and its very interesting
I can find my left-right brain conflict on this site:
I see a letter and I pronounce a word in my head, but generally the letter gets typed and I make an error.
While googling for that prof. I came across this guy who seems to be on the same page:
Since destruction of self is a pre-requisite in many enlightenment stories, it sounds like a person who has switched off/temporarily disabled/removed the dominance of their left brain.