Your Brain in Love: Part 1 – When Love is a Many-Splendored ThingEd. note: This week, in the run-up to Valentine’s Day, we’re featuring a 5-part series about the neuroscience of love and romance. At the end, we’ll put the full series on our website. Enjoy!

Ever fallen madly in love? Researcher Helen Fisher has spent her academic life trying to figure out what’s going on in the brains of those who are in the heady, butterflies-in-the-stomach throes of passionate romantic love. Fisher has scanned the brains of young paramours and found that when they’re focusing on the object of their affection, a whole host of brain parts start lighting up. One of the two most important regions was initially a little surprising to Dr. Fisher. First, she found that the caudate nucleus—part of the primitive reptilian brain—is highly active in these amorous individuals. As expected, she also saw the brain areas associated with dopamine and norepinephrine production light up. Both are brain chemicals associated with pleasurable activities and excitement.

Fisher puts it best when she says, “No wonder lovers talk all night or walk till dawn, write extravagant poetry and self-revealing e-mails, cross continents or oceans to hug for just a weekend, change jobs or lifestyles, even die for one another. Drenched in chemicals that bestow focus, stamina and vigor, and driven by the motivating engine of the brain, lovers succumb to a Herculean courting urge.”

Fisher also notes that other parts of the reward system, like the one that activates when you’re eating chocolate, play a role during this phase of love. She supports the hypothesis that like chocolate, being head over heels in love is addictive. Of course, dopamine is what gets released when you take a hit of cocaine, too—so it’s not surprising that other research suggests that for the brain, a bad break-up is like kicking a drug habit.

You can see a video of Helen Fisher talking about the love, the brain, and why people cheat here:

Read Part 2: Love and Marriage

Read Part 3: The Neuroscience of Date Night

Read Part 4: Oxytocin, the Love/Hate Hormone

Read Part 5: No Room for Romance? Try Music Instead (But Not Junk Food)