We’re used to hearing about people spreading colds and flu. But according to a new study in the Journal of Personality and Social Psychology, there’s another human condition that’s equally contagious: loneliness.
“Loneliness spreads across time,” says John Cacioppo, a neuroscientist and psychologist at the University of Chicago and one of the authors of the study. “It travels through people. Instead of a germ, it’s transmitted through our behaviors.”
The longitudinal study, conducted by the University of Chicago, the University of California-San Diego and Harvard, interviewed more than 5,000 people over the course of 10 years, tracking their friendship histories and their reports of loneliness. Participants were part of the Framingham Heart Study, which has studied cardiovascular risks in people in Framingham, Mass., since 1948 and has since been expanded to include other research topics such as loneliness and depression.
In the study, researchers found that lonely individuals tend to move to the fringes of social networks (and, no, we’re not talking about Facebook or Twitter here), where they have fewer and fewer friends.
But before they move to the periphery, they “infect” or “transmit” their feelings of loneliness to their remaining friends. With fewer close relationships, these friends then become lonely and eventually move to the fringes of the social network, again passing their loneliness on to others. Thus, the cycle continues.
“When people get lonely, they’re more likely to interact negatively with others they encounter,” says Cacioppo. “If you have two neighbors and they’re friends and one becomes lonely, they’ll start to treat the other less friendly. Ultimately, they’re less likely to be friends.”
Ironically, loneliness can not only make you feel more socially isolated, it can make you more anxious, more shy and cause you to believe you have poor social skills. Cacioppo says previous research also shows that loneliness can make people less trustful of others and can make the brain more “defensive.”
“Your brain tells you people are rejecting you,” he says. “Loneliness may warp the message that you’re hearing.”
A biological signal
While loneliness can be “contagious,” Cacioppo says it’s important to note it’s not a disease, nor is it a personal weakness. It’s actually a biological reaction, much like hunger or thirst or pain.
“Society tends to think of it as an individual characteristic — there are just loners,” he says. “But that’s the wrong conception of what loneliness is. It’s a biological signal motivating us to correct something that we need for genetic survival. We need quality relationships. We don’t survive well on our own.”
Studies, in fact, show loneliness can actually be harmful to both mental and physical health, leading to depression, high blood pressure, increases in the stress hormone cortisol, and compromised immunity.
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Unfortunately, quality friendships can sometimes be difficult to find or maintain in our busy, BlackBerried society.
“I get lonely sometimes but I tend not to seek people out to do things because they’re all married or committed or need to find a babysitter and then it just turns into a circus,” says Tina Kurfurst, a 46-year-old database coordinator from Seattle. “I went out to dinner with some people from work the other night and one of the women kept saying, ‘Wow, you’re funny, why don’t we hang out more often?’ And I just thought, ‘Well, because you have a husband and a 12-year-old and a 17-year-old and it just doesn’t happen. You don’t have time for me.”
Video: Loneliness may be contagious Stephanie Smith, a clinical psychologist with a private practice in Erie, Co., says she tries to encourage her lonely patients — which can range from college students to stay-at-home moms to high-powered CEOs — to find at least one friend in their same situation.
“If you have kids, know at least one other person who has kids,” she says. “Or if you don’t, find someone who doesn’t. It’s important to have people in your life who share your interests and your stage of life.”
But you don’t have to have a slew of BFFs.
“Sometimes people get overwhelmed and think ‘I need to have 15 best friends,’” she says. “But it doesn’t need to be that big. One friend, one relationship, can be very powerful.”
Facebook and Twitter are no substitute for the real thing, though.
“If you’re isolated due to a disability or a spouse with Alzheimer’s, then Facebook can be a real boon,” says Cacioppo. “But if you’re spending your time on Facebook rather than face-to-face with friends, it increases your loneliness. It’s about quality. Lonely people use social networks as a substitute; non-lonely people use them to synergize the relationships they already have. The person with 4,000 friends on Facebook may well be a very lonely person.”
The secret, says Cacioppo, is realizing loneliness is nothing more than your body sending you a signal.
“All normal humans feel lonely at some point in time, just like they feel hunger and thirst and pain,” he says. “But while we have cupboards filled with food, taps for water and medications for pain, we don’t have anything comparable for loneliness. I’m not saying you need a cupboard full of friends, but if you feel lonely, pay attention and take the time to repair it.”
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