[Listen to Robert Levenson's full interview with Science Today.]
Love can be a battlefield. So what makes a successful relationship?
Psychologist Robert Levenson (known for his work on the “marry me” gene) and his team at UC Berkeley had a hunch that the key to a relationship’s stability was the ability to deal with conflict.
So they gathered 156 middle-aged couples who had been married a long time. Every five years, these couples came to the lab and the researchers watched them interact and resolve arguments (while monitoring different physiological markers):
“When we started, we were convinced that it was all going to be about regulating the husband’s [emotional] temperature because men tend to get uncomfortable with conflict and want to solve it quickly. That was our hunch, but it turned out to be just the opposite. Couples who seemed to get happier over the 20-year study were those who could regulate the wife’s emotions.” 
The interesting thing was that it didn’t matter how quickly the husband cooled down after an argument, but it made a lot of difference how quickly the wife cooled down.
So is this a gender thing? Levenson isn’t certain that the results indicate gender differences. The BIG caveat is that this is only a group of 156 couples (of a particular place and generation, with particular educational, ethnic, and religious backgrounds):
“In these groups there tends to be a confounding of gender with power. So in many of these marriages the husband has more power. In the older group they may have that because they’re the one who is more likely to have had a career.
And so we’re often not sure with these kinds of findings whether it has to do with women or it has to do with the person in the relationship who has less power.”
Levenson has also done research with same-sex couples (some of the only studies of this kind). In male/male and female/female couples, he noticed a similar pattern where the more powerful person ended up looking like the male in heterosexual relationships. Power and the desire to change a relationship were more powerful factors than a person’s gender.
The person with less power tends to want more change in the relationship. They tend to be more frustrated and less satisfied when the issues they raise aren’t resolved. ”It would be quite reasonable to think that the less powerful person would be the one for whom cooling down would be more critical,” he explains.