Love may be in the air, but it is also in your brainwaves. Xiaomeng Xu is part of a growing group of researchers using neuroimaging to reveal new insights about falling in love - and staying that way. Xu has found that the experience of love in the brain is consistent across cultures and can even predict the endurance of a relationship.
Xu, now a postdoctoral research fellow at Alpert Medical School and the Weight Control and Diabetes Research Center of Miriam Hospital, describes her early research as investigating one question: "What does it look like when you're really, madly in love?"
To answer that question, Xu went to the experts. She joined Arthur Aron, a professor of psychology at State University of New York at Stony Brook, who runs an interpersonal relationships lab. In 2005, Aron did one of the first studies looking at intense romantic love with a brain scanner.
Xu decided to replicate that study, this time using Chinese subjects. Her results were published in the journal Human Brain Mapping in 2010 and a follow-up of this study is currently under review for publication.
"In close relationship literature, there's this really large difference between Easterners and Westerners on self-report questionnaires," Xu said. American subjects described intense feelings of passion in new love, while Chinese subjects seemed to describe more pragmatic feelings. "Some people in the field jumped to the conclusion that there's this cross-cultural difference in terms of the experience of love," she said. "I didn't buy that."
Xu hypothesized that cultural conventions were causing Easterners to downplay their passionate feelings, while Westerners were more inclined to exaggerate them to match a Hollywood ideal. In order to test the true experience of love, rather than relying on self-reports, she turned to neural imaging. "I'd had no neuro background at all," Xu said. "It kind of helped because if I'd known how much work would go into it, I might have been more hesitant." Instead, she enlisted the help of "neuro guru" Lucy Brown of Albert Einstein College of Medicine to help interpret the brain scans she collected.
While spending a summer at the Chinese Academy of Sciences, Xu recruited 18 college-aged people who proclaimed themselves "passionately in love" and used functional magnetic resonance imaging to capture their brains while they looked at pictures of a loved one as well as those of a neutral acquaintance.
The difference between the two scans revealed the areas of the brain that are activated by passionate love - both reward regions of the brain and motivation systems like those that are activated by drugs.
"It's that obsessive quality," Xu explained. "Not just that hanging out with a person makes you happy, but that when you're not with them there's a sense of craving almost." As Xu had suspected, the areas of brain activation for the Chinese participants were just like those of their American counterparts.
To put a new spin on her experiment, Xu also surveyed the participants 18 months later and revisited 12 of the participants four years after the original fMRIs to search for a correlation between their brain scans and later relationship status. Six were still in their relationships, six were not. She found that less activation in the areas related to judgment, emotion regulation and hunger often correlated with higher satisfaction in and commitment to their relationships.
"The data suggest that a long-term relationship involves suspending negative judgment and extending the concept of oneself," Lucy Brown said. Xu's paper on these follow-up findings is currently under review to be published.
Xu is not limiting her study to brand new relationships. Xu and collaborators have also been investigating what leads to early intense love brain reactions in long-term couples. They found that couples who reported feeling "madly in love" after several years had brain scans to back up their self-reports and also had one major thing in common: participating in self-expanding activities on a regular basis. Taking part in challenging and novel activities as a couple has been known to strengthen relationship bonds, but Xu is among the first to verify it in the lab.
Xu herself has been with her husband for 10 years now. "We've been through the gamut of the early stage, (wanting) to spend every second with this person and onwards," she said. "We do try to practice what we preach - to keep doing self-expanding things."
And there is always more to explore when it comes to brains in love. "We're starting to look at the picture. We know a lot from observational, behavioral and survey research about what predicts who will stay together," Aron said. "But to actually be able to see some of the brain responses is just a whole new angle of getting at that issue."