Loneliness: Human Nature and the Need for Social Connection

John T. Cacioppo's groundbreaking research topples one of the pillars of modern medicine and psychology: the focus on the individual as the unit of inquiry. By employing brain scans, monitoring blood pressure, and analyzing immune function, he demonstrates the overpowering influence of social context-a factor so strong that it can alter DNA replication. He defines an unrecognized syndrome, chronic loneliness; brings it out of the shadow of its cousin, depression; and shows how this subjecti...