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The magic of the first kiss

A kiss is just a kiss. Or is it? Whether you're looking for love or happily coupled this Valentine's Day, take a moment to ponder the incredible moment that is... the first kiss.

Related Stories Right Way to Kiss, Science Online, 28 Aug 2003

Valentine's is a day dedicated to lovers. And as all lovers know, the magic starts with that first kiss. So what's exactly happens in order for that perfect first kiss to become intoxicating?

When the first kiss works it's powerful - over 90 per cent of lovers, irrespective of age, can remember exactly where and when it occurred.

Moreover, that first kiss is a dealmaker or breaker because over 60 per cent of first kisses, for both men and women, are a failure terminating any chance for romance.

Well before that first kiss occurs the eyes are conveying important information to the brain, which in turn has a tremendous influence upon our feelings associated with love. Next time you get a chance watch how new lovers look at one another - it's thrilling.

After the eyes have helped set the mood in the brain, just prior to approaching that first kiss the prospective lover involuntarily tilts his or her head, either to the right or left. It turns out that about two-thirds of us tilt to the right.

It's not right-handed related but rather correlated to head tilt direction while in utero as the foetus moves and tilts its head. Also, over 80 percent of nursing mother's cradle their babies to the left thus the infant must turn its head to the right. Conditioning for feelings of love, affection and sustenance clearly begin very early in our lives.

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Smooch

Assuming that first kiss feels just right, then the brain nerves used for hearing, seeing, smelling and tasting are in overdrive; collectively affecting the expression on the lover's face.

As the kiss heats-up blood vessels expand to allow more oxygen to the brain, breathing becomes deeper, irregular and pupils dilate (perhaps explaining why many lovers close their eyes).

Invariably there will be tongue contact, more often than not initiated by the male but more about that later. The tongue allows us to sample our partner's taste with the assistance of over 9,000 little bumps or taste buds spread across its surface.

All five senses are sending messages to the brain; that is, tens of billions of nerves are firing rapidly throughout the body.

Lips are very sensitive to pressure, warmth and cold; they contain the highest concentration of nerve cells on our body. There are over 100 billion complex nerve cells liberally spread throughout the lips. They are the gateway to tiny neurotransmitter molecules that help trigger hormone release including dopamine, oxytocin, serotonin and adrenaline.

That first passionate kiss causes dopamine to spike in the brain. It's a give-me-more insatiable hormone all about pleasure; when we first fall in love and have those over-the-moon thoughts, that's dopamine. Incidentally, it affects the same part of the brain as cocaine, making us crave for more. It also causes energy to elevate, loss of appetite, sleeplessness and even intoxication.

Oxytocin is a love hormone that is crucial in promoting affection and attachment so that when dopamine wanes oxytocin surges. That's why a kiss, hug or tender caress helps to maintain a strong sense of attachment for lovers. By the way, oxytocin is also responsible for causing pleasurable female pelvic jolts during orgasms.

Serotonin controls our emotions and movement of information to the brain, including those obsessive feelings and thoughts about our new lover. When that first passionate kiss brings love into our world the high levels of serotonin mimic those associated with obsessive-compulsive disorder.

That first passionate kiss can cause some people to experience a sensation of weak-in-the-knees due to high levels of adrenaline, which are also spiking in the brain.

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Feeling the love

Women intuitively use that first kiss to assess whether a male is healthy and possessing "good-genes." If that first kiss feels and tastes good, that's an excellent start in a bonding relationship.

The other important link in determining whether that first kiss makes the grade is body scent. The highest concentration of scent or sebaceous glands are near the nose, face and neck. Each of us has a unique scent and the human nose is able to detect over 9,000 different molecules. When you press your nose over your prospective lover's neck or jaw-line, only you will know if their scent is just right.

Lastly, there's a valid evolutionary reason why men slip women a wet, sloppy tongue kiss. Male saliva contains testosterone, a hormone in short supply in females. Just a few male testosterone molecules raise women's libido, readying that passionate scene for intimacy.

And all that just in one kiss!

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