What’s your big idea?

Worldwide polls suggest that most people take love to be romantic, everlasting, and unconditional, confining it to that special relationship they have with the one person they call their soulmate—or would call their soulmate, if they ever met the “right” person. To me, this popular view of love suggests a worldwide collapse of imagination that poignantly limits the benefits that love might otherwise carry for us all. As an emotions scientist, working from the perspective of evolutionary psychology, I’ve come to a very different perspective on love, one that can require a radical shift.

Suppose you could, for a moment, disregard all the love myths, love stories, and love songs lodged in your head, and drop down to your heart, and see love from that perspective. I’m not talking about some metaphorical heart, or the cartoon hearts we see everywhere this Valentine’s season, but your physical heart, beating away inside your chest. By listening to what your heart has to say, we can begin to appreciate love from a new angle. And suppose we go beyond your heart, into your bloodstream, and touch base with your white blood cells, the very front lines of your immune system. What does love look like from that perspective? This is my big idea: in Love 2.0, my aim has been to give voice to your body’s definition of love.

From your body’s perspective, love is, first and foremost, an emotion—a dynamic mind-body process that rolls through you for a few micromoments any time you connect with someone else over a shared positive feeling. We tend to think of emotions as private events, confined to one person’s mind and skin. Love knows no such boundaries, however. Evidence suggests that when you really “click” with someone else, a discernible yet momentary synchrony emerges between the two of you, as your gestures and biochemistries, even your respective neural firings, come to mirror one another in a pattern I call positivity resonance. Love, from your body’s perspective, is a biological wave of good feeling and mutual care that rolls through two or more brains and bodies at once. Your body needs these micromoments of positivity resonance just like it needs good food and physical activity. These micromoments, our research shows, nourish both you and the other person. The more of these micromoments you each have, the more each of you grows happier, healthier, and wiser.

How do you measure love?

As for all emotions, it’s best to converge on the concept of love by using many different types of measures. Chief among these are people’s daily reports of the degree to which they feel close and “in tune” with the people with whom they interact each day. We also measure behavioral synchrony, both through people’s own reports of it, and by painstakingly coding people’s nonverbal behaviors from videos taken while they are interacting. Perhaps most significantly, however, we measure how these experiences of connection and synchrony relate to biological markers of health, like cardiac vagal tone, blood pressure, oxytocin, and changes in gene expression within the immune system.

What does the latest in neuroscience and evolutionary psychology tell us about what love is and how it is manifested in biology and chemistry?

Our latest evidence tells us that micromoments of positivity resonance fortify the connection between your brain and your heart, making you healthier day by day. Decades of research has shown that people who are more socially connected live longer and healthier lives. Yet precisely how social ties get under the skin to affect health has been one of the great mysteries of science. My research team recently discovered that when we randomly assign one group of people to learn new ways to create more micromoments of love in daily life, we lastingly improve the functioning of the vagus nerve, a key conduit that connects your brain to your heart. This discovery opens a new window onto how micromoments of love serve as nutrients for your health. Although it may seem surprising that an experience that lasts just a micromoment can have any lasting effect on your health and longevity, we’ve learned that there is a positive feedback loop at work here, an upward spiral between your social and your physical well-being. That is, love not only makes you healthier, but being healthier also builds your capacity for love.