It's not enough to get a head shot.
You have to destroy the hypothalamus (IF, BIG IF, I remember my anatomy correctly). Which is a region of the brain almost dead center, directly behind the bridge of the nose. This is why getting shot "between the eyes" is instantly incapacitating. It completely cuts off all nerve signals to the entire body.
Could be the hippocampus too... Can't remember. Is there a biologist around here?
