Ceridwen Dovey, The New Yorker: 

For all avid readers who have been self-medicating with great books their entire lives, it comes as no surprise that reading books can be good for your mental health and your relationships with others, but exactly why and how is now becoming clearer, thanks to new research on reading’s effects on the brain. Since the discovery, in the mid-nineties, of “mirror neurons”—neurons that fire in our brains both when we perform an action ourselves and when we see an action performed by someone else—the neuroscience of empathy has become clearer. A 2011 study published in the Annual Review of Psychology, based on analysis of fMRI brain scans of participants, showed that, when people read about an experience, they display stimulation within the same neurological regions as when they go through that experience themselves. We draw on the same brain networks when we’re reading stories and when we’re trying to guess at another person’s feelings.