Love is complicated, scientifically speaking. There's no single, specific "love chemical" that surges through our bodies when we see our beloved, and we can't point to a specific corner of the brain where love resides.

Still, scientists have measured real changes in our bodies when we fall in love: an ebb and flow of signaling molecules. In that early lustful phase, sex hormones like testosterone fuel the libido (in both men and women). The dopamine highs of new attraction have been compared by some scientists to the effects of cocaine use.

The anxiety associated with new romance has been linked to low levels of serotonin in the brain. And some researchers say they see similarities in the way serotonin is regulated in the early phases of love and the way it is modulated in obsessive compulsive disorder.

Meanwhile, our brains start producing more oxytocin, a chemical that is crucial to, among other things, the bonding of mothers and infants.

Comparisons to drug use and compulsion aren't perfect (obviously there's a lot more fancy chemistry going on in our brains), but they do seem to speak to our experience. Love can feel addictive and all-consuming.

In Skunk Bear's new video ballad, we explore the symptoms of love and their neurological causes. Why does your heart race when you see your crush? What gives you that feeling of butterflies? And why does love make us act so dumb? This love ballad is our Valentine's gift to you.

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