A Valentine's Day look at the science of love and attraction

As Valentine’s Day approaches, it seems like a good time to take stock of what we know about how the brain handles love.

We all have some control over the person we choose to fall in love with, of course. But after that, our brain’s biology takes over.

In early infatuation, our brains are flooded with chemicals that make us feel good — the same ones triggered by drugs like marijuana.

Biological anthropologist Helen Fisher has scanned the brains of 100 people at different stages of love. Those who had just fallen head-over-heels, she found, had activity in the part of the brain that releases dopamine, a chemical involved in reward and motivation.

This brain region is nestled close to areas that orchestrate thirst and hunger — essential for survival.

“I had long thought romantic love was an emotion or series of emotions,” says Fisher, who is affiliated with both Rutgers University in New Jersey and the Kinsey Institute at Indiana University. “But it’s basically a drive that evolved millions of years ago to allow us to focus our mating energy on one person at a time.”

Sex, of course, is intimately related to love — but also distinct, says Fisher, author of Anatomy of Love, among other books. You can fall in love first, with sexual attraction following; the act of sex can trigger the release of brain chemicals that trigger romance and/or emotional bonding; or you can have sex with no love at all.

“These aren’t phases of love, but brain systems,” Fisher says.

When people fall in love, they can still see flaws in their partner, she says, but their brains literally overlook them.

Love turns off part of the brain behind the forehead, called the prefrontal cortex, that is involved in critical thinking and decision-making. Focusing deeply on the other person is rewarded with extra activation of the dopamine reward system. “It’s like somebody’s camping in your head,” she says.

But research shows that those feelings of passionate, early love only last for 1-2 years, said Mona Fishbane, a Chicago-based clinical psychologist.

That doesn’t mean love is doomed, she and others say.

Couples who said they were still in love decades into their relationship showed an interesting pattern of brain activation, Fisher found. Brain scans suggested they were particularly empathetic, able to control their stress and emotions, and able to overlook the negative and focus on the positive.

“If you really want happiness in a long-term partnership, you want to be empathetic, accentuate the positive and control your own stress,” she says. To keep triggering brain systems that evolved for falling in love, Fisher suggests couples do novel things together — new restaurants, new vacation spots, having sex in new ways — to trigger the release of dopamine and help sustain romantic love.

Physical touch also helps to trigger the release of oxytocin that can lead to bonding. Fall asleep in your partner’s arms, Fisher recommends, and make sure to find time in your busy lives to have sex.

“Sustain that sex drive, sustain feelings of romantic love, sustain feelings of attachment, think positive thoughts, control your own emotions, be empathetic and say nice things to your partner — that’s what the brain says,” she concludes.

Fishbane, who wrote the book Loving with the Brain in Mind, focuses her research on couples whose relationships are fraying. For them, she says, there is different neurobiology at work.

When one partner harshly criticizes the other, that can trigger the fight-or-flight response, she says, with stress hormones flooding from the amygdala — part of the brain involved in controlling emotions such as fear.

That stress is particularly reinforced, Fishbane says, if the criticism repeats a pattern from childhood. A man is much more likely to respond defensively to his wife’s criticism, for example, if it echoes the criticism he heard as a boy from his mother.

“He may feel inadequate — doesn’t know what he wants, doesn’t know how to please her. His survival strategy is to defend, to withdraw,” Fishbane says.

That emotional response makes it harder to take a step back, controlling emotions and being empathetic.

“When the amygdala gets that activated, it hijacks the brain,” Fishbane says, shutting down the more reflective, thoughtful brain regions. “It’s much easier to get overwhelmed by emotion than to calm yourself down. … I call it the Dance of the Amygdalas.”

The key to restoring happiness and maintaining a strong relationship long term, Fishbane says, is to deactivate those emotions, perhaps by articulating them, and then thinking through them.

Instead of criticizing a partner for being distant, for instance, you could ask what’s wrong and say that you really miss them, she suggests.

Once they break this high-stress pattern, couples can get back to being nurturing, compassionate, curious and empathetic — to being in love, Fishbane says. “You can have a voice in a way that brings your partner in rather than pushes them away.”