Why falling in love gives you butterflies

Dr. Daniel Amen, a psychiatrist, neuroscientist and the author of several books including “Change Your Brain, Change Your Life,” agrees that these bodily symptoms point more to lust than love, and cites the activation of the basal ganglia in the brain as a crucial factor.

“Falling in love — or rather falling in lust — activates those pleasure centers housed in [the basal ganglia] which causes an immediate physiological response. The heart beats fast, your hands will get cold and sweaty and you’re super-focused on that person,” Dr. Amen tells NBC News BETTER, adding: “Your stomach will do somersaults.”

The butterflies feeling is partially your body saying I'm stressed but I'm motivated to do something or see this person again.

This last effect spotlights the connection between our brain and our belly, a relationship that has been receiving more interest of late, with some recent research suggesting that a healthy gut is essential for a healthy brain.

“Your limbic or emotional brain activates the vagus nerve that goes from the brain to your gut,” says Dr. Amen. “When you get nervous, or when you get excited (as I explain to my patients, it’s the same feeling, but it depends on your interpretation of it) this nerve is stimulated that activates the gut.”

Dr. Prause points to a region in the brain called the cingulo-opercular network, aka the salience network, which is associated with motivation and may trigger in the early stages of a relationship. “The butterflies feeling is partially your body saying I'm stressed but I'm motivated to do something or see this person again. It’s actually the same when you want to punch somebody in the face; the body interprets it in different ways.”

Our brain isn’t just pushing magic buttons to get our heart rate to pump up, or our cheeks to turn red; it’s releasing potent chemicals when our crush walks by.

“Dopamine is the first neurotransmitter to respond to seeing an attractive person,” says Dr. Scott Carroll, a psychiatrist and the author of “Don't Settle: How to Marry the Man You Were Meant For”. “Your dopamine levels instantly increase because you've detected something desirable in your environment. You are instantly focused and excited by the person you see. Your norepinephrine levels also increase which further focus you, but also make you nervous and a bit cautious.”

And just how intensely you feel this nervousness could depend on your personality. “Shy people have low serotonin which causes the norepinephrine to go up even higher, producing the high anxiety associated with meeting a new person, especially if they are attracted to them,” adds Carroll.

We also experience the release of oxytocin, but perhaps not as quickly as one would expect. “Oxytocin, your bonding neuropeptide, starts to increase [when] you to start to feel comfortable with and close to the person.”

I must admit, as much as I love my fiancé, I don’t really get butterflies anymore when I see him, unless we’ve been apart for quite a while. I also feel a sense of safety and accountability with him rather than the surprise and spontaneity or our early days.

Dr. Nicole Gravagna, a neuroscientist and behavioralist who authored “MindSET Your Manners” suggests that these calm, jitter-free waters are a good sign.

“True love is a well-being experience that does not include nervousness or excitement,” Gravagna says. “True love does not resemble addiction in the body.”

Dr. Carroll adds that at around this five-year relationship marker, dopamine and endorphins “drop to only mildly elevated levels compared to the pre-relationship level.”

And so, the real work of true love begins. It’s not as breathlessly exciting as the butterflies, but it’s so much more fulfilling, and certainly a lot less stressful.

NEXT: Why this marriage therapist says a 'good enough' relationship is one that lasts a lifetime

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