DAVIS, Calif. —Â One tends to be more about sex, the other more about love. But in their early phases, long-term and short-term relationships are practically indistinguishable from one another, a recent study suggests.
Couples’ paths start to diverge and the relationship changes after the couple begins engaging in sexual activity, according to the study’s authors at the University of California, Davis.
“Some of the most interesting moments in these relationships happen after you meet the person face-to-face, but before anything sexual has happened,” says lead author Paul Eastwick, associate professor of psychology at UC Davis, in a media release. “You wonder ‘is this going somewhere?’ or ‘How much am I into this person?’ It is somewhere around this point that short-term and long-term relationships start to diverge, and historically, we have very little data on this particular period of time.”
Long-term relationships have their ups and downs and the people involved typically strongly view their partners as their future spouses, or at least think they could be spouse material. But researchers found it’s impossible to tell which relationship will continue in the long-term and which will flame out quickly, at least at the start.
So Eastwick and his team attempted to chart the lifetime of long- and short-term relationships, from the first time a couple decides to break up. The examined the relationships of more than 800 individuals from a wide range of ages, and used a cutting-edge “relationship reconstruction” survey to examine people’s events and experiences to build patterns of long- and short-term relationships.
They found that it takes some time for the different types of relationships to distinguish themselves with differing patterns.
“Long-term and short-term trajectories typically pull apart after you’ve known someone for weeks or months,” says Eastwick. “In the beginning, there is no strong evidence that people can tell whether a given relationship will be long-term and serious or short-term and casual.”
The authors say that on average, when a relationship turns sexual, the rate of romantic interest begins to wane for those in short-term flings. Yet in long-term relationships, that interest continues to rise.
“People would hook up with some partners for the first time and think ‘wow, this is pretty good.’ People tried to turn those experiences into long-term relationships,” says Eastwick. “Others sparked more of a ‘meh’ reaction. Those were the short-term ones.”
The study is published in Journal of Experimental Psychology: General.