In our internet-crazed world, attention is drawn in a million different directions at once as we multi-task through every day. In a single 5-minute span, the average person will divide their time between working on a task, checking email, chatting with a couple of people (via chat, skype, etc.), keeping an eye on twitter, monitoring their smartphone, and interacting with co-workers. This type of ADD-like behaviour causes stress levels to rise, and lowers our productivity.
When you read a book, all of your attention is focused on the story—the rest of the world just falls away, and you can immerse yourself in every fine detail you’re absorbing. Try reading for 15-20 minutes before work (i.e. on your morning commute, if you take public transit), and you’ll be surprised at how much more focused you are once you get to the office.