The human brain long ago evolved a mechanism for rewarding us when we encountered new information: a little shot of dopamine in the brain each time we learned something new. Across evolutionary history, compulsively seeking information was adaptive behavior.

Every status update you read on Facebook, every tweet or text message you get from a friend, is competing for resources in your brain with important things like whether to put your savings in stocks or bonds, where you left your passport, or how best to reconcile with a close friend you just had an argument with.

Getting new information through Web-surfing almost always feels more rewarding than having to generate new information in the work that is in front of us. It therefore takes increasing amounts of self-discipline to stay on task.

Daniel Levitin Quotes