Neil Swidely in The Boston Globe Magazine:
"We've gone from an American ethic that championed the lone guy on a horseback to an ethic of managing multiple data streams," says Dalton Conley, a sociology professor at New York University and author of the new book Elsewhere, U.S.A.: How We Got From the Company Man, Family Dinners, and the Affluent Society to the Home Office, BlackBerry Moms, and Economic Anxiety. "It's very hard for people to unplug and be alone -- and be with the one data stream of their mind."
What's fueling this? Conley says it's anxiety borne out of a deep-seated fear that we're being left out of something, somewhere, and that we may lose out on advancement in our work, social, or family lives if we truly check out. "The anxiety of being alone drives this behavior to constantly respond and Twitter and text, but the very act of doing it creates the anxiety."
This is particularly true among young people, mainly because they don't know life when it wasn't like this.