But it's clearly not a physical area of the brain, since many stroke victims do recover the ability to speak.
Scholars and researchers have been beating on this question for the last century, so it's equally interesting that there's no solid answer on it yet.
Actually, it is a physical area - Broca's and Wernikie's areas; left temporal lobe for most folks. The amount of recovery after a stroke is inversely poprotional to the length of time that neurons went without oxygen