New research out of UC Davis suggests that when couples who are romantically involved interact, their heart and respiratory rates sync up.
But that doesn't mean you should bring a pair of heart rate monitors to scout out potential partners on your first date. When study participants were paired with someone outside their relationship, neither their heart rates nor their breathing closely matched.
To conduct their research, which was funded by the National Science Foundation and published in the International Journal of Psychophysiology and Emotion, the psychologists in one study placed couples a few feet apart in a quiet, calm room and instructed them not to talk or touch. In another, the couples were asked to mimic each other without speaking. In both instances, heart and respiratory rates were closely matched.
"We've seen a lot of research that one person in a relationship can experience what the other person is experiencing emotionally, but this study shows they also share experiences at a physiological level," Emilio Ferrer, a UC Davis psychology professor who conducted the studies, says in a news release.
For all the cynics, the study has its limitations. For starters, the sample size is small -- only 32 couples participated. It also took into account only heterosexual partnerships, and only in a very limited setting.
But if you're in a relationship and want to give your significant other something outside the box on Valentine's Day, here's an excuse to shell out for a couple of heart rate monitors. At the very least, you get to test your partner's sense of humor.