" In one fascinating study, conducted at Washington University’s Dynamic Cognition Laboratory and published in the journal Psychological Science in 2009, researchers used brain scans to examine what happens inside people’s heads as they read fiction. They found that “readers mentally simulate each new situation encountered in a narrative. Details about actions and sensation are captured from the text and integrated with personal knowledge from past experiences.” The brain regions that are activated often “mirror those involved when people perform, imagine, or observe similar real-world activities.” Deep reading, says the study’s lead researcher, Nicole Speer, “is by no means a passive exercise.”35 The reader becomes the book. "

― Nicholas Carr , The Shallows: What the Internet Is Doing to Our Brains