The science of romance: Brains have a love circuit

? Like any young woman in love, Bianca Acevedo has exchanged valentine hearts with her fiance.

But the New York neuroscientist knows better. The source of love is in the head, not the heart.

She’s one of the researchers in a relatively new field focused on explaining the biology of romantic love. And the unpoetic explanation is that love mostly can be understood through brain images, hormones and genetics.

That seems to be the case for the newly in love, the long in love and the brokenhearted.

“It has a biological basis. We know some of the key players,” said Larry Young of the Yerkes National Primate Research Center at Emory University in Atlanta. There, he studies the brains of an unusual monogamous rodent to get a better clue about what goes on in the minds of people in love.

In humans, there are four tiny areas of the brain that some researchers say form a circuit of love. Acevedo, who works at the Albert Einstein College of Medicine in New York, is part of a team that has isolated those regions with the unromantic names of ventral tegmental area (VTA), the nucleus accumbens, the ventral pallidum and raphe nucleus.

The hot spot is the teardrop-shaped VTA. When people newly in love were put in a functional magnetic resonance imaging machine and shown pictures of their beloved, the VTA lit up. Same for people still madly in love after 20 years.

The VTA is part of a key reward system in the brain.

“These are cells that make dopamine and send it to different brain regions,” said Helen Fisher, a researcher and professor at Rutgers University. “This part of the system becomes activated because you’re trying to win life’s greatest prize — a mating partner.”

One of the research findings isn’t so complimentary: Love works chemically in the brain like a drug addiction.

“Romantic love is an addiction; a wonderful addiction when it is going well, a horrible one when it is going poorly,” Fisher said. “People kill for love. They die for love.”

The connection to addiction “sounds terrible,” Acevedo acknowledged. “Love is supposed to be something wonderful and grand, but it has its reasons. The reason I think is to keep us together.”

But sometimes love doesn’t keep us together. So the scientists studied the brains of the recently heartbroken and found additional activity in the nucleus accumbens, which is even more strongly associated with addiction.

“The brokenhearted show more evidence of what I’ll call craving,” said Lucy Brown, a neuroscientist also at Einstein medical college. “Similar to craving the drug cocaine.”