Reading a newspaper article, for example, does not give you the same experience because it is true and can actually cause more worry and stress in the brain, especially if that article contains something that pertains to you directly.
The experience of reading fiction is very different than reading nonfiction because of the different ways fiction is structured and characters develop. In this case, we are talking about nonfiction writing without a clear plot structure and characters like a newspaper or magazine article, rather than a memoir or a creative nonfiction piece.
Although technically non-fiction, we would categorize the experience of reading narrative nonfiction such as a memoir as the same experience as reading fiction because of the narrative arc and character development that takes place in these types of pieces. When you read fiction or narrative nonfiction, you are able to forget about yourself for a while.
Oatley says, "You go sit somewhere quietly, or you go lie on a couch, or go to bed, you put aside your own concerns and now you take on the concerns of Anna Karenina or Emma Bovary, or whoever it happens to be. So you then start to experience what life was like from within a different mind."
Reading fiction helps you to put your mind at ease, and when you stop reading, you are more refreshed and refocused for your day. This may, actually, be why so many people enjoy reading a good book before bed. When your mind is clear, you can sleep better.
In Oatley's study, participants were given a personality test, then one group was asked to read a fiction piece and one group was asked to read a non-fiction piece that was similar to the fiction one. After the reading, participants took the personality test again. It was shown that those who read the fiction piece had a slight change in their personalities.
According to Oatley, "There are similar cognitive processes associated with understanding the real world and understanding the fictional world, so when we try to understand what's going on in a piece of fiction... it's analogous to people trying to figure out how real people are thinking and feeling."
This, apparently, explains the change in personality they were seeing, and many small changes over time can, in fact, change your life.