What New Love Does to Your Brain

New love can consume our thoughts, supercharge our emotions and, on occasion, cause us to act out of character.

“People pine for love, they live for love, they kill for love and they die for love,” said Helen Fisher, a senior research fellow at the Kinsey Institute at Indiana University. “It’s one of the most powerful brain systems the human animal has ever evolved.”

Scientists have studied what is happening in our brains when we are in those early, heady days of infatuation, and whether it can actually alter how we think and what we do. Their findings suggest that song lyrics and dramatic plotlines don’t overstate it: New love can mess with our heads.

Experts define “romantic love” as a connection deeper than lust, but distinct from the attachment associated with a long-term partnership. In a few of the small studies that have examined this googly-eyed state, researchers put people in the early stages of a romantic relationship (typically less than a year) in M.R.I. scanners to see what was happening in their brains while they looked at pictures of their paramours. They found that the participants showed increased activity in areas of the brain that are rich in the neurochemical dopamine and control feelings of wanting and desire. These regions are also activated by drugs like cocaine, leading some experts to liken love to a sort of “natural addiction.”

Studies on prairie voles (yes, you read that right) back up these findings. The rodents are one of the few mammal species that mate for life, so researchers sometimes use them as a scientific model for human partnerships. Studies show that when these animals pair up, the brain’s reward system is similarly activated, triggering the release of dopamine.

“Romantic love does not emanate from your cerebral cortex, where you do your thinking; it does not emanate from the brain regions in the middle of your head, linked with the limbic areas, linked with emotions,” said Dr. Fisher, who conducted one of the first human studies on the topic and, along with her role at the Kinsey Institute, is the chief science adviser to Match.com. “It’s based in the brain regions linked with drive, with focus, with motivation.”