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The Science of Falling in Love—A Hormonal "Cascade" (Phase One)



A romantic relationship often starts off filled with infatuation.

Midst the excitement, however, is embedded fear that things may be headed for disaster.

Whether this fear of loss is real or imagined, the agony of a lover’s heart can take powerful heights. Love can turn to hate, a relationship can become a major stressor, and hostile breakups can have detrimental consequences on children.

“These violent delights have violent ends,” warned Shakespeare’s Friar Laurence, and his words are not far from what relationship researchers have observed.

Indeed, there are measurable warning signs that precede relationship dissolution. To understand how relationships get wrecked, we must understand how couples build (or erode) trust.

Essentially, what makes good relationships work?

  • Can this be real?

  • Is she the one?

  • Is he the one?

  • Can you even really know?

These questions keep many lovers dazed day and night. A crystal ball won't offer answers; they come by carefully analyzing some patterns that make or break a relationship.

Let's explore Phase One of the science of how falling in love starts.

Phase One: A Hormonal "Cascade" called "Limerence"

You know that initial “cascade” of hormones and neurotransmitters that accompany the feeling of falling in love. There's a term for it--“limerence,” a term coined by Dr. Theresa Crenshaw in her book The Alchemy of Love and Lust.

Not every person sets this off on you, says researcher and author, John Gottman in Principia Amoris; a person must smell right, feel right, and touch right for this complex cocktail to be turned on.

While this phase is not necessary for marriage, it is expected in our Western culture to experience this rush of feelings.

So how does this cascade of hormones toss lovers into such feelings of high?

Some major hormones contribute to you feel madly in love.

  • Phenylethylamine (PEA) and Pheromones create the magic moments of “fire sparkling in a lover's eyes.”

  • Dehydroepiandrosterone (DHEA) is a natural aphrodisiac often called the “mother of all hormones.” It increases our cognition, metabolic rate, and immune system and may influence whom we find attractive.

  • Oxytocin creates the bonding and attachment experience between romantic partners (as it does with a mother and child). It's crucial in sexual function, offering feelings of being wanted and loved. However, it can lead to poor judgment! Falling in love is an apt phrase, because we are “in a haze” as oxytocin surges in our brain. We wear blinders and may not see red flags!

  • Estrogen in women increases receptivity to her partner’s initiating.

  • Dopamine causes us to seek pleasure, anticipation, and the feeling that something really amazing and enjoyable is about to happen. Having too much can create problems.

  • Serotonin is needed to sufficiently chill us out from a dopamine rush. Without it, we get lost in pleasure seeking. Women have more Seratonin, which facilitates warmth and sociability.

  • Vasopressin is also known as “The Monogamy Molecule for Males." It increases possessiveness and motivates warding off rivals. Remember that third person next to Romeo and Juliet’s duo? Yes, Paris was his name.

As enjoyable as Phase One is, it is also short-lived.

Some decide to seize the moment and get married in this intoxicating phase, but many couples roll into Phase Two as they consider a commitment.

So what happens in Phase Two?

Here's a little preview: as oxytocin starts wearing off, the very thing that attracted us to our lover becomes irritating. We begin asking questions such as: Can I trust you? Will you be there for me? Do you have the characteristics to make me happy?

More on this next time.

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