When people are wrapped up in a story, they stop day dreaming and are fully present. In that level of focus, what we call attentional narrowing, means that the senses, the imagined experiences of a story become real to our on brains. Your brain turns all into real sensory information, even though it's fiction. And if you feel like you're someone that's pretty resistant to story, i would ask you, have you ever cried reading a book or watching a t v show or a film? If so, you've become so enraptured in a story that you're crying for someone who probably doesn't even exi that's amazing.