A racing heart, clammy palms and flushed cheeks are telltale signs that you’re in love. Yet little is known about what happens inside the brain when Cupid hits.

Georgetown University Psychologist Abigail Marsh told MedicalDaily.com that love feels good because it involves the release of feel-good hormones.

YourAmazingBrain.org wrote that according to Helen Fisher of Rutgers University, the three stages of love -- lust, attraction and attachment -- are each driven by different hormones and chemicals.

Sex hormones -- estrogen and testosterone -- drive the lust stage.

In the attraction stage, when those in love think of nothing else, a group of neurotransmitters come into play. These include dopamine, norepinephrine and serotonin.

Attachment bonds couples together long enough to raise a family. Scientists believe two major hormones are involved in the attachment stage -- oxytocin and vasopressin.

Long regarded as "the love hormone," oxytocin is a powerful hormone released during orgasm.

"People who excite romantic feelings in us probably also trigger increases in oxytocin, which results in this increase in dopamine when you find that person that you want to stick with,” Marsh told MedicalDaily.com.

The love hormone acts as a neurotransmitter in the brain. Unlike most hormones, oxytocin is produced in nerve cells rather than glandular cells. It is also believed that cuddling, hugging or kissing boost oxytocin levels, which help enhance social bonding.

A new study suggests that oxytocin also stimulates the male brain reward center, increasing partner attractiveness and strengthening monogamy.

Under the influence of oxytocin, researchers said that two areas of the brain responsible for feelings of reward and pleasure lit up when men saw their partner's faces. Seeing other women had the opposite effect and suppressed feelings of pleasure.

Vasopressin, the other important hormone in the attachment stage, is released after sex. It’s role in long-term relationships was discovered when scientists looked at the prairie vole, a rodent found in North America.

Prairie voles indulge in far more sex than is necessary for reproduction. Like humans, they form fairly stable pair bonds. When male prairie voles were given a drug that suppresses the effect of vasopressin, scientists noticed that the bond with their partner immediately deteriorated.

Although much is known about neurotransmitters like oxytocin, there are still unknowns as to what actually sets off these feelings of love. Researchers are in the dark about how love is like other emotions. So the whole process of falling in love is still a complete mystery.

Sources:

Abrams, Lindsay. "Study: Oxytocin ('the Love Hormone') Makes Men in Relationships Want to Stay Away From Other Women." The Atlantic. Atlantic Media Company, 16 Nov. 2012. Web. 8 Mar. 2014.
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Borreli , Lizette. "Oxytocin, Love Hormone, Fuels Romance: How Your Brain Works When You're In Love." Medical Daily. IBT Media Inc. , n.d. Web. 8 Mar. 2014.
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Goodman, Brenda. "How the 'Love Hormone' Works Its Magic." Consumer HealthDay. HealthDay, n.d. Web. 8 Mar. 2014.
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"How the 'Love Hormone' Works Its Magic – WebMD." WebMD. WebMD, n.d. Web. 8 Mar. 2014.
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"Oxytocin: the monogamy hormone?" Medical News Today. MediLexicon International, n.d. Web. 8 Mar. 2014.
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"The Science of Love." BBC News. BBC, n.d. Web. 6 Mar. 2014.
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Reviewed March 13, 2014
by Michele Blacksberg RN
Edited by Jody Smith