Looking back at old yearbook photos, one might be able to tell a lot more than who had acne or a timeless fashion sense, according to a small but intriguing new study.
Researchers in the April 5 issue of the journal Motivation and Emotion proposed that smiling or frowning facial expressions in children and young adults can predict their marital status later in life.
By adapting standard of facial expressions developed 30 years ago by famous psychologist Paul Ekman, researchers categorized and then ranked the degree to which survey participants smiled in hundreds of yearbook photos.
In one sample, the researchers ranked 306 photos from college psychology alumni ranging in age from 23- and 87-years-old. In another sample, the researchers ranked 349 college alumni from various majors with an average age of 46, all of whom reported at one time being in a serious committed relationship.
Across both samples, people whose smiles ranked in the top 10 percent had a divorce rate of about 1 in 20, while those whose smiles fell in bottom 10 percent rate had a divorce rate of 5 in 20, or five times more likely to get a divorce.
The study could not provide definitive evidence. There's a high divorce rate anyways, there were more women than men in the study and the participants were virtually all Caucasian -- but lead author Matt Hertenstein said he was aware of the limitations and still intrigued by the results.
"It does suggest that potentially smiling and a positive disposition can affect the people who live around us," said Hertenstein, who is an associate professor of psychology at DePauw University in Greencastle, Ind.
Hertenstein said that this finding is only a correlation and therefore can't answer why or how a smile might later predict marriage status.
Take the example of Hollywood, a cadre of successful, beautiful people who smile at every turn. The group is riddled with celebrity splits, tiffs and reconciliations, as well as the occasional happy marriage.
"People's smiles or lack thereof were not their destiny in terms of their marital status later in life," said Hertenstein. "We found plenty of people who were not smiling at all and had long-lasting relationships."
Still, there may be some truth behind the researchers' claims.
"The strength of a smile in photos in childhood probably correlates strongly with a positive vibe a person is giving," said Susan Heitler, psychologist and author of "The Power of Two: Secrets to a Strong and Loving Marriage." "Smiles correlate with being in a relaxed, positive emotional state, able to hear concerns and be responsive with other people."
Heitler pointed out that a positive attitude and willingness to listen leads to a stronger ability to understand others' concerns and begin to compromise -- the bedrock of strong partnerships.
"The ability to come to win-win decisions when there's a conflict correlates quite high with marital satisfaction," Heitler said.
But while smiling may predict the ability to have good relationships, frowns are a powerful indicator of future relationship problems.
"There are some people who look like a perpetual storm cloud and when you approach them you feel a little tense," Heitler said. "Having the positive is great. Having the negative is more predictive."
But smiles can be misleading and there are a few major exceptions to the rules that seem to govern marital success or failure.
"People who are narcissistic and a little bit hypomanic can be generally very happy. They're life-of-the-party people. But they're more focused on themselves and not so good at hearing others," Heitler said. "In one-on-one relationships, they can be difficult partners. It's all about them and their way."
Hertenstein thinks his research should just be taken as a general trend across populations.
"We just found a correlation," he said. "We know these two things are linked in some way or somehow."
Although he couldn't say how, Hertenstein was willing to give a few hypotheses.
"Maybe [people] who smile a lot attract happier people, or maybe people who are obedient to the photographer may be obedient to people in the relationship," he said.
The most surprising part of the study to Hertenstein was the predictive value of what psychologists often call the "thin slicing" -- or examining a small example of a behavior and then inferring characteristics or traits based on that slice.
"I do think it's pretty surprising that you could make a prediction with some accuracy over a number of people using a split second of their emotions," said Hertenstein.