“A typical office worker was getting interrupted by various media stimulation every three minutes in 2004, according to research by Gloria Mark, a professor at the University of California at Irvine. That was before the spread of instant messaging and Facebook. By 2013, the interruptions were every two minutes; such intrusions came either from a person responding to a new stimulus—like an incoming email—or from an internal urge to change tasks, say, to write a new email.”