Love can make you feel euphoric, foolish, happy, obsessed, distracted, passionate, exhausted and pretty much everything in between -- so it should come as little surprise that falling in love does quite a number on your brain.
When you fall in love with someone, a whole host of changes are taking place in your brain and body to create all that passion and euphoria, and of course the less desirable effects, too.
While you're enjoying some time with your significant other this Valentine's Day, take a moment to marvel at the science of love -- and to appreciate the incredible effect your partner has on your noggin!
Scroll down for eight crazy things that love does to the brain.
1. Falling in love causes a major hormone rush. When you first fall in love, you experience a rush of hormones to the brain -- including oxytocin, the "love hormone," the "pleasure hormone" dopamine, and sex hormones like estrogen and testosterone. Other hormones, like adrenaline, make the heart beat faster. This influx of hormones plays a major role in those intense feelings of fluttery excitement, attraction and euphoria.
2. Love can become an addiction. We all know that falling in love can lead to cravings and obsessive thoughts, and the desire to spend every moment with your partner. Sound like an addiction? That's because it is. Now, neuroscience research has shown that love quite literally is like a drug: Falling in love activates the same system in the brain as cocaine addiction.
"Romantic love is an obsession, it possesses you," Dr. Helen Fisher, anthropologist and author of Why We Love, said in a TED talk about the brain and love. "You can't stop thinking about another human being... Romantic love is one of the most addictive substances on Earth."
3. Love activates the opioid system. Romantic love and attraction can activate the brain's opioid system -- that's right, like heroin and opioid pain killers -- which is the part of the brain involved in "liking" something. Scientists have suggested that this system may have evolved to help us choose the best mate by giving rise to rewarding feelings when we see that potential partner.
4. Love can make your serotonin take a nosedive. Research has associated romantic love with low serotonin levels, which is also a central feature of obsessive-compulsive disorder. This could play a role in explaining the single-minded focus on the object of their affection that many lovers experience.
5. Love can zap your focus. Anyone who's been in love knows that it can be more than a little distracting, and now we understand why. Neuroscientists have linked passionate love with intense changes in emotion and attention, as well as reduced cognitive control -- meaning that you're less able to control your attention.
6. Love can strengthen your empathy and ability to process emotions. The type of love that's cultivated through the practice of loving-kindness meditation activates the brain's empathy and emotion-processing centers, while also reducing activity in brain areas associated with self-focused thought. Loving-kindness meditation also gets us in touch with our feelings by increasing gray matter volume in brain areas associated with emotion processing.
7. Different stages of love can change your brain activity differently. A study published last year in the journal Frontiers in Human Neuroscience found that MRI scans could be used to accurately determine what stage of romantic love a person was in based on their brain activity. While falling in love activates the brain's reward center, breaking up decreases activity in the reward center, and also causes sharp decreases in activity and functional connectivity in a part of this center that's associated with expectation of rewards.
8. Love can get in your brain and stay there for life. A 2011 study found similar activity in certain brain regions among longtime, happily married couples and among couples who had recently fallen in love. The researchers suggest that these brain regions might provide clues as to how some couples stay deeply in love for decades.
The bottom line? Love can last.
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