What is love actually?

You may have less control over your emotions than you think. Katrina Hendley discovers what happens when we fall in love

You know that all-consuming whirling dervish of a feeling when you’re falling in love? The inability to concentrate, the counting of hours before you can see your lover again, the way your heart beats wildly when you see the object of your affection?

When you experience something this powerful, surely it means a real meeting of hearts and minds – that you’ve met your soulmate at last?

Well, maybe. On the other hand, it could be a series of chemical reactions in your brain causing what could, quite reasonably, be called a temporary madness.

For centuries, the nature of love was debated by philosophers, authors and poets. More recently, scientists have joined the fray, with anthropologists, psychologists and neuroscientists researching this nebulous and uniquely human phenomenon. As a result, we know more about love than ever – at a biological level at least.

Prominent among these ‘love scientists’ is Dr Helen Fisher, an anthropologist at Rutgers University, New Jersey, who has been researching the subject for more than 35 years. Her book, Why We Love: The Nature and Chemistry of Romantic Love, sets out three distinct phases of love – lust, attraction and attachment – each involving a distinct brain system with specific biochemistry.

First up we have good old lust, which is driven by testosterone and oestrogen in both men and women. These are the hormones that pique our interest in someone.

The second phase is attraction and this is where romantic love, with all its madness, kicks in. This is the stage where you’re obsessed with your new love – where you are, in short, lovestruck.

What causes this mayhem? It’s down to three potent chemicals in your brain that help to send messages back and forth in the nervous system: adrenaline, dopamine and serotonin.

Your sweaty palms and racing heart? That’ll be down to higher levels of adrenaline. The dilated pupils, increased energy and restlessness associated with new love? That’s dopamine at work.

Dopamine is the chemical that keeps us coming back for more of that loving feeling. It is associated with the brain’s desire and reward system (it’s also stimulated when we drink caffeine) and this is why we keep coming back for more – we crave that chemical high.

The third chemical, serotonin, may actually change the way we think. While in this infatuated stage, our serotonin levels are lower than normal – in fact, they’re very similar to the level in people with obsessive-compulsive disorder, which might explain why we can’t think of anything else but our loved one.

As if all this wasn’t enough, it seems that parts of the brain dealing with social judgement and negative emotions are switched off in the early stages of love. This effectively impairs our critical faculties so that we idealise the object of our affection, seeing them through rose-tinted glasses and remaining blissfully unaware of their flaws.

So, all those cliches are true: love is indeed blind, it really is a drug and it’s also a kind of temporary insanity. This state of affairs obviously can’t go on forever or we’d never get on with the rest of our lives. We’d also be exhausted.

Thankfully, as amazing as this infatuated stage is, it tends to last anywhere between six months and three years before another, more sedate system takes over. Unless you’re a teenager, that is.

Part of what makes those adolescent years such a bumpy ride is that teenagers experience the attraction phase more strongly than adults and fail to enter the next phase. So it’s not just a short attention span that causes them to move from one relationship to another: this behaviour is down to their biochemistry – they really can’t help it.

Adults, though, do enter the next phase, which is attachment – that sense of closeness and contentedness you feel with a long-term partner.

This stage is helped along by the hormones oxytocin and vasopressin, both of which are stimulated by physical contact – from holding hands to making love. They deepen your feeling of attachment and make you feel closer to your partner: vasopressin makes you more likely to be monogamous.

But this isn’t the end of the story. Dr Robin Dunbar, Professor of Evolutionary Anthropology at Oxford University and the author of The Science of Love and Betrayal, believes that endorphins are behind the creation of longer-term relationships:

“Oxytocin is actually relatively short-lived and in order to build these lifelong, intense relationships, we need something more robust, more persistent – that’s where endorphins come in.”

Similar in effects to opiate pain relievers, endorphins produce a general sense of wellbeing, allowing us to feel calm, relaxed and happy. Like oxytocin, they are stimulated by physical contact, but in a steady relationship build up over time.

They are also more addictive, inducing a drug-like dependency, so that when our partner is absent we crave to have them back. It seems the longer people are together, the more likely they are to stay that way.

Finally, there are pheromones – chemicals that we give off and which have an effect on others, probably through smell. “I think there’s clear evidence that these do work at some level,” agrees Dunbar.

He cites research carried out at speed-dating evenings where each woman had a little liquid dabbed on to her upper lip. Some had a pheromone in this liquid, others didn’t – and those with the pheromone were much more positive in their ratings of the men they saw, and were more likely to express an interest in seeing them again. “As a rule, we’re more dominated by vision, but smell certainly plays a part in attraction,” says Dunbar.

Why is falling in love so complicated? In the end, it’s designed to make sure we ‘lock on’ to someone and settle down with them long enough to rear children. It’s all part of that ultimate biological instinct, survival of the species. So are we entirely at the mercy of our biochemistry?

Not quite, says Dunbar. “There is a series of decision points where you seem to assess your relationship, despite all these unconscious components compelling you down the slippery slope,” he says. “You go in so far, then you stop and you think, ‘Do I want to go any further here?’. So we have the conscious and the subconscious working at the same time.”

If reducing love to a series of biochemical processes ruins the romance, take comfort in the fact that Dunbar admits we don’t know everything yet.

“We don’t have all the answers,” he says. “At the end of the day, it’s a purely emotional response. If you don’t get that, love is never going to work and no amount of cold explanation will change that. You can’t think about it: you just have to let nature take its course.”

And if it all goes wrong, you can always take comfort in the fact that it’s just those pesky chemicals that made you fall in love in the first place.

The Science of Love and Betrayal by Professor Robin Dunbar will be published by Faber and Faber in April

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