Cupid isn't as busy as we'd like to think, writes Chrissie Russell
For centuries writers have waxed lyrical about the inexplicable mysteries of love, star-crossed lovers and heart-fluttering romance.
But it appears they might have to eat their words. Scientists have been probing the secrets of the heart's desire and found out that love is all in our heads.
It turns out it's our brains and not our poor hearts that make us fall head over heels. And it's our hormones, not cupid, that finds us a mate.
One scientist leading the surge of interest into the science of love is Robin Dunbar, an evolutionary psychologist at the University of Oxford.
In recent years Dunbar has studied hundreds of loved-up case studies and discovered that most couples will lose two friends to keep a romantic partner.
But most recently he's turned his attention to why we feel the way we do when experiencing that crazy little thing called love.
Using MRI scans, Dunbar found that when people in love looked at pictures of the object of their desire, the rational part of their brains shut down.
However, just in case losing our mental faculties of reason isn't enough to seal the deal, the brain makes falling in love even more appealing by also releasing a heady cocktail of chemicals.
She found they showed high levels of three neurotransmitters: dopamine, adrenaline and serotonin -- producing feelings of craving, motivation and ecstasy.
The wave of pleasure the brain emits when falling in love isn't unlike the rush an addict experiences when taking heroin or cocaine.
In fact, according to research published in the Journal of Sexual Medicine last week, the area of the brain associated with attaching value to attraction and labelling it 'love', is the same part of the brain that is involved in drug addiction.
Love is a habit formed when sexual desire is rewarded. The brain stores away the good memory of it and keeps us coming back for more. Which is why a jilted lover can feel like an addict going cold turkey.
The reason the brain goes to the bother of creating this sensation of falling in love isn't so we can spew out reams of great literature, pen mediocre song lyrics or spend thousands of euro on lingerie and new haircuts.
No, bluntly put, it's so we'll have babies.
"It's all done to make sure we procreate," says Professor Luke O'Neill, Director of Trinity Biomedical Sciences Institute.
"All our systems have evolved to evolve the species. If we lost interest in falling in love then we'd just go off and do something else and that would be the end of it."
We might like to think it's a meeting of minds or that there's a karmic element to our romantic unions but picking a partner comes down to how their genetic make-up sits with our own.
"Scientific evidence at the moment shows we select a mate by smell," explains Professor O'Neill. "We do it without thinking, but it's smell that helps us find a partner that best suits us in terms of producing the healthiest offspring."
Once we've sniffed out a suitable mate, the brain starts working to help us form the attraction needed to get to the sex stage.
But thankfully nature wants our young raised in a protective environment and instead of rolling over and going to sleep post-lovemaking, the brain kicks into action to try and ensure the mate hangs around.
Fisher found that after sex the brain released the 'bonding' hormones vasopressin and oxytocin -- the same hormone that is released during childbirth to bond mother and child.
In this way the chemical rush of first love transmutes into a more long-term bond.
All those assertions that love is like a butterfly might have been vague and unhelpful, but surely they're better than knowing it's a product of hormones, synapses and chemicals?
"The research does demystify it a bit. Knowing we're all just animals doesn't leave much room for the soul," says Professor O'Neill
He adds: "Science doesn't have all the answers. The area of desire is of huge interest and there's still a lot of investigation to be done into what attracts women at different times in their ovulation cycle, how pheromones work and what stimulates female sexual desire.
"That's a big one -- the hunt is always on for the female Viagra."
Romance vs Science
Romantic Fiction: "Whoever loved that loved not at first sight?" ( Christopher Marlowe)
Science Fact: It's probably more like love at first sniff. According to Professor Luke O'Neill: "We select mates that best complement our immune system and that's done by sense of smell and pheromones". Sight comes in next when we start looking for females with fertile, child-birthing hips and hairy, testosterone-filled males.
Romantic Fiction: "Love is the drug" ( Bryan Ferry)
Science Fact: It's actually very similar, the brain activity monitored in couples in the first flush of love showed the same pathways of the brain illuminated as in someone who has taken drugs.
Romantic Fiction: "I thought love would last forever -- I was wrong" (WH Auden)
Science Fact: Not necessarily, Auden. Helen Fisher identifies three stages of love: lust, attraction and attachment. In the final stage, powerful bonding hormones are released with the intention of producing lasting commitment.
Romantic Fiction: "To be wise and love exceeds man's might" (Shakespeare)
Science Fact: Both Shakespeare and indeed Beyoncé were right -- we do go a bit crazy in love, with the logical prefrontal cortex shutting down to give the emotional parts of the brain a free ride.
Romantic Fiction: "We come to love, not by finding a perfect person, but by learning to see an imperfect person perfectly" (Sam Keen)
Science Fact: True. The brain makes sure new lovers idealise their partner and explain away flaws so that they make it a leap of faith into the next stage of love.