People tell stories. They love to tell stories. In their heads and to others. It is the same thing. When you are thinking, you are telling a story to yourself, a narration, which may have nothing to do with your current environment or situation. Lost in thoughts. The externalization of that is irrelevant.
When you are having a discussion with someone it is not a discussion with yourself. You have to see the other. To understand him. To feel him. And then respond accordingly. It is a dance of perceptions finding common ground. Otherwise talking has no purpose. You can clearly see the other drifting into his own mind-patterns. Sometimes talking like a robot. The limited, conditioned patterns are dictating the words, like an auto-cue demanding to be read or a theater instigator screaming.