Broca's area and Wernicke's area could quite possibly have nothing to do with the OP question (talk in our mind), and of course conciousness. I tend to look at it as Broca's and Wernicke's as mechanical, moving parts...in compared to a state of conciousness and "talkin in the head" as talking in the head could be done with someone that has no knowledge of language, this person can still talk in his/her head.
It's such a fabulous question, and I hope we answer this holy grail of neuroscience in my life time.
You never know... It could be more of a question of Physics :)