The intensity of orgasm is sublime, but the gentle love cocktail that follows is what helps relationships to endure.
Analyse a story or script, and you can break down the narrative into parts: exposition, inciting incident, rising action, conflict, climax, falling action, and resolution. Sex is much the same. Yet whether it’s a story or intercourse, we often focus our attention on the parts that bring us to climax and orgasm – the Big-O, where most of the tension lives. Magazines give advice on how to make partners orgasm or how to be better at foreplay, but we rarely talk about the part that comes afterward. It’s a shame because that falling action is, according to recent studies, where the majority of relationship satisfaction comes from.
You’ve probably heard the term ‘afterglow’, defined as the aura of satisfaction and closeness that comes after sex. It’s the feeling that makes two sweaty people want to snuggle rather than rush off to shower. Now, Amy Muise, a psychologist at York University in Canada, reports that it’s the seemingly boring pillow talk, and not so much ‘spicing things up’, that helps love last.
Muise, who studies how sexuality impacts on relationships, set out with colleagues to learn which part of sex made people feel more connected to their partners. In a study published in 2014 in the Archives of Sexual Behavior, they reported that it was what followed intercourse itself. The length of ‘post-sex affection’ ranged from zero minutes to several hours, the researchers learned. And those who spent more time snuggling were more satisfied with their relationships.
Going against what your cousin’s friend’s older brother might have once told you, Muise also found that afterglow was even more important to relationship satisfaction than the duration of foreplay or sex itself. ‘When you look at Cosmo magazine or those types of things, you hear a lot about foreplay, and spending time, and trying lots of positions. That might be somewhat important,’ she told me. But once her team added the effects of after-sex affection to their data, it completely wiped away any bump sex itself gave to relationship satisfaction.
Afterglow itself might be mostly a chemical love cocktail, and what we know about the neurological aspects of monogamous relationships comes from an unassuming rodent known as the prairie vole. These burrowing creatures live in grasslands throughout North America, have small rounded ears, and are no bigger than the palm of your hand. Yet unlike 97 per cent of all animals, they form monogamous partnerships. For more than four decades, this particular species of vole has been responsible for many major findings about why humans pair up and fall in love. It’s a happy accident that the word ‘vole’ itself is an anagram for ‘love’ – even though the prairie vole is one of the few voles that bonds with its mate.
In 1992, researchers reported that single female prairie voles placed with a male for at least 24 hours ‘exhibited a strong social preference’ for him versus a strange male – whether or not the two had mated. If the voles were placed together for fewer than 24 hours without mating, no connection was formed. The twist is that females who ‘cohabited and mated for six hours’ showed signs of attachment to that male. Like humans, prairie voles can form attachments without having sex first but getting to know each other in the biblical sense makes a relationship stronger faster.
And it all begins with a pharmacy-worth of chemicals zipping around in the brain. During sex, the brain is flooded with neurotransmitters such as dopamine, oxytocin, testosterone and vasopressin, just to name a few. Each of these chemicals plays a multitude of roles. Though dopamine is often referred to as a chemical associated with reward (and helps to make pleasurable behaviours from drug use to gambling or sex feel addictive), it plays a much more complicated role. Parkinson’s disease kills the neurons that create dopamine leading to tremors and stiffness of the limbs.
Likewise, people with attention-deficit hyperactivity disorder (ADHD) often have low levels of dopamine which helps to explain the reduced motivation and inattention associated with the condition. For people who suffer from post-traumatic stress disorder (PTSD), dopamine often floods the brain during periods of anxiety. These are all a long way from love.
Sex is an accelerant, firing the neurons that release dopamine, oxytocin and other chemicals linked to pair-bonding and love
Yet many symptoms of stress – heightened alertness, sleeplessness, loss of appetite – can be almost euphoric when caused by a new romance. Given the dual nature of many of these chemicals, it is no surprise that oxytocin (sometimes thought of as the ‘cuddle hormone’) doesn’t just promote pair-bonding but can intensify memories of negative social experiences. First discovered in prairie voles, oxytocin release during sex allows couples to form a monogamous bond. When researchers cut off the flow of oxytocin, these voles behaved much the same as their non-monogamous cousins. In many ways, the chemicals associated with sex and pair-bonding tell the brain that this moment is important and worth paying attention to – for better or for worse.
As Martin Portner, a neurologist living in Brazil, wrote in Scientific American Mind in 2008, people need more than arousal to experience an orgasm: ‘It requires a release of inhibitions and control in which the brain’s centre of vigilance shuts down in males; in females, various areas of the brain involved in controlling thoughts and emotions become silent.’ Fireworks are only worth noticing when they happen on a backdrop of a dark night sky. Women’s brains tend to experience this effect more strongly than men, Portner writes. In a 2009 study in Human Brain Mapping, researchers found that genital stimulation led to deactivation in parts of the brain associated with inhibiting emotional responses. Rather than a sign that nothing is happening in the brain, this respite might be what allows partners to lower their guard after sex and allow deeper connections to form.
‘Sex is an accelerant,’ said Larry Young, a researcher at Emory University in Georgia who studies the neurobiology of social relationships (and who has worked with prairie voles for decades). He describes sex as causing a ‘firing of neurons’ that releases dopamine, oxytocin and other chemicals that we associate with pair-bonding and love. ‘If I take my wife out to a nice dinner with candles and flowers on the table, I can guarantee she’ll be releasing dopamine and oxytocin,’ he told me. The dinner-date conversation between two neuroscientists must be an eavesdrop for the ages. ‘But sex is something that really just greatly amplifies the situation.’