Despite the way it feels, loneliness often has nothing to do with being alone. For some people, feelings of isolation are sharpest during times that are in fact defined by togetherness — celebrations or the holidays, for instance. Walk into a bustling shopping mall or a buzzing holiday party this time of year, and even within a crowd — or perhaps especially in a crowd — it's possible to feel unbearably alone.
New research from experts in neuroscience and social science may give us a clue as to why. Although we tend to think of it as a self-contained emotional state — a condition that affects people individually, either by circumstance or by dint of an antisocial personality — researchers now say that loneliness is more far-reaching than that. John Cacioppo, a psychologist at the University of Chicago, believes it is a social phenomenon that exists within a society and can spread through it, from person to person, like a disease. And while everyone feels lonely once in a while, for some it becomes a persistent condition, one that has been associated with more serious psychological ills like depression, sleep dysfunction, high blood pressure and even an increased risk of dementia in older age.
For Cacioppo's latest study, published in the Journal of Personality and Social Psychology, he partnered with leading social-network scientists Dr. Nicholas Christakis of Harvard University and James Fowler of the University of California, San Diego, who make up the team best known for its series of studies showing that emotional states and behaviors — including happiness, obesity and quitting smoking — can propagate like a wave throughout a network of people. To examine whether the contagion effect existed with loneliness, the researchers used the same data set that Christakis and Fowler had mined for their earlier studies — the Framingham Heart Study, an ongoing trial originally begun in 1948 to identify risk factors for cardiovascular disease. Thanks to the meticulous way the trial was initially set up, with investigators noting the close family members and friends of each participant to ensure follow-up over the years, Cacioppo, Christakis and Fowler now had access to a rich social network for each volunteer in their study — from family members and friends to colleagues and neighbors.
Cacioppo and his team focused on the children of the original Framingham cohort, which included more than 5,200 middle-aged men and women. Starting in 1983, more than 4,500 volunteers were asked to fill out three questionnaires, spaced two years apart, about how many days in the previous week they had felt lonely. Because most of the participants' friends and family members were also part of the Framingham study, the scientists could track, over time, whether one person's report of loneliness had any impact on the feelings of isolation in other members in his or her social network. Researchers were thus able to rule out the possibility that lonely people simply congregated with other lonely people, or that a shared environmental event, such as a fatal fire in the neighborhood, could have triggered mass feelings of loneliness.
