Happy Valentine’s Day! Here’s what happens to a brain in love

For Valentine’s Day, let’s forget love’s mysteries and get down to the biological basics that fire some of our fiercest emotions.

Jane Austen once wrote: “You pierce my soul. I am half agony and half hope.”

Here’s why, Jane.

Helen Fisher, biological anthropologist, has done extensive research on the topic. In an interview Tuesday with the L.A. Times, the author and Rutgers visiting professor described some of her findings -- culled from longtime married couples still “madly” in love, as well as from love’s sad rejects.

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Fisher has based several books on research she did with colleagues. They looked at three groups of 15 to 18 people each: young people who had fallen in love recently -- and ecstatically; 15 men and women who had been dumped recently; and couples in their 50s and 60s married, on average, 20 years who didn’t just love their partners, Fisher stressed, but were deeply “in love” with them.

They conducted MRIs on participants’ brains. Among those intensely in love, major activity was seen at the base of the brain in the tiny ventral tegmental area, Fisher said. It’s a part of the brain that produces the stimulant dopamine (thus, the exhilaration, elation and singular focus of new love). Dopamine traveled to the caudate nucleus, where it integrated with “cognitive thinking” and “emotional sensations.”

Bottom line?

Fisher had thought romantic love “was an emotion, and indeed it is, but it’s basically a drive that comes from very primitive parts of the brain.”

Ooh, primitive drive. That’s promising. But this next part isn’t very romantic.

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From her studies, Fisher determined that romantic love was one of three brain systems that had evolved to direct reproduction: 1) sex drive, prompting you to go out and seek partners; 2) romantic love, allowing you “to focus your mating energy on one individual at a time”; and 3) attachment, “to motivate individuals to remain together long enough to complete species-specific parenting duties,” as her study says.

And it can get messy:

For love’s rejects, perhaps the most remarkable finding was activity in the nucleus accumbens -- a region that grows active with all addictions, “cocaine, nicotine, alcohol, opiates, amphetamines, gambling addiction, food addiction, sex addiction,” the whole bit, Fisher said. Even those happily in love had activity in the nucleus accumbens.

“I was able to prove,” she said, “that romantic love is an addiction, and it’s a very positive addiction when things are going well but a very negative addiction when things are going poorly.”

In a 2008 Ted presentation, Fisher said crimes of passion become easier to understand, with chemicals in the brain providing obsessive focus, motivation and the willingness to take inappropriate risks.

That’s failed love. What about forever love? We all deserve a happily ever after -- is there chemistry for that?

“We’re beginning to find some of the biology of what makes a happy partnership,” Fisher said.

--Empathy: Those in the long-term love relationships took a questionnaire prior to the MRI, rating their satisfaction with their relationship. Those who rated their satisfaction highest on the form also showed activity in regions of the brain linked with empathy.

--Controlling your emotions: The same group showed activity in the brain linked with the ability to control emotions. So if you’re able to feel empathy and can control your emotions when things get rough, you are more satisfied with your partner.

--Ignoring what you don’t like: One of Fisher’s colleagues took the love experiment to China. There, 18 people who were madly in love were studied. Three and one-half years later, they were studied again. Half were still in love; half had ended the relationship. Were there differences in the brains of those two groups? Yes.

“The most dramatic difference was in the prefrontal cortex, a brain region linked with what scientists call positive illusions,” Fisher said. It’s “the simple ability to overlook what you don’t like about somebody and focus on what you do.”

But, that doesn’t mean you can be happy with just anyone. “It’s not going to work if you don’t pick the right person,” she said.

“You could inject me with dopamine and I will never fall in love with Hitler.”

So there you have it. Love, stripped bare.

Knowing the brain activity behind love hasn’t spoiled it for Fisher, though. She said it had only increased her appreciation of the emotion and intensified her feelings about it.

“If somebody falls in love with me, I’m relatively convinced they are still going to love me tomorrow because I know how it works .… If anything, it’s remarkably enriched my understanding of people and myself and the whole concept of love.”

“I walk down the street and look in baby carriages and say, ‘Oh boy, are you in for the joys and sorrows of life.’ ”

*Name the movie: “You’re breaking up with me because I’m too ... blonde?”

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*”Legally Blonde.” Follow me at @AmyTheHub