“Your love, your love, your love is my drug.” When it comes to the brain, these lyrics to a catchy Ke$ha song may just ring true. New research is unraveling the neural mechanisms behind falling, and staying, in love.

A team of scientists from Rutgers University, Albert Einstein College of Medicine, and the State University of New York at Stony Brook have conducted a series of studies over several years to understand what goes on in your brain when you’re in love. In a study published in the Journal of Neurophysiology, scientists scanned the brains of 10 women and seven men who claimed to have fallen intensely in love in the past year and a half.

When the participants looked at a picture of their beloved, activity was detected in the caudate nucleus and the ventral tegmental area, a brain region that produces the pleasure-inducing the neurotransmitter dopamine. These regions play major roles in reward and motivation. Put simply, this brain system gets activated by pleasurable activities like eating chocolate, having sex, or doing drugs. And presumably, by falling in love.

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In their next study, the scientists scanned the brains of individuals who were rejected by their beloved, but claimed to still be in love with him or her. When looking at a photograph of the rejector, the same brain regions were activated, suggesting that the reward and motivation system is activated even when you’re unhappily in love.

Activation was also found in the forebrain, an area that has been implicated in cocaine craving and addiction. These findings might help explain why rejection is so hard to get over. According to one of the researchers in the study, Helen Fisher, “Romantic love is an addiction; a wonderful addiction when it is going well, a horrible one when it is going poorly.”

So, if love is like a drug, can the high last? Thankfully for all of the romantics out there, it appears as though it can. In their most recent study, published in January of this year, the researchers looked at the brains of people who insisted they were still passionately in love with their significant other, even after years of marriage.

When the participants looked at a photo of their spouse, they found patterns of neural activity that were similar to those seen in individuals who were in the early stages of intense love. However, they also found activation in brain areas that are important in attachment and in modulating anxiety and pain, which was not found for those newly in love.

Long-term love, then, may be the best drug of all.