“Love is an endless mystery, for it has nothing else to explain it.” – Rabindranath Tagore
Love: poets, artists, musicians and philosophers have sought for centuries to unravel its mysteries and yet it remains forever wild and elusive. But whilst we can’t completely explain love, modern science can give us an insight into some of the tell-tale signs of longing. From beating hearts to butterflies, there’s a lot of complex biology, neurochemistry and psychology that goes into giving you that gooey feeling.
So first off, why do we fall in love? There’s no easy answer. Some evolutionary psychologists suggest that humans have an inbuilt need to form long-term relationships as a form of insurance. Partnerships provide protection and ensure mutual support for children, and to develop these partnerships we need an impetus to stay together.
Meanwhile, phycologist Arthur Aron has suggested that we are motivated primarily by the abstract need to “expand the self and to increase our abilities and our effectiveness.” Intimate relationships can help us to develop and move beyond a life dominated by the self and grow as a person.
Genetics and chemistry are also important factors. According to behavioural neuroscientist, Mark B. Kristal, to fall in love, we must be exposed to “visual, regular olfactory, auditory and tactile cues” happening in “the proper time, order and place.” That means we need to experience the right pheromones and chemical responses to forge a soft spot for someone.
What’s more, research has shown that when it comes to long-term relationships we’re often attracted to people who are genetically similar to ourselves. We also frequently rate people as more attractive when they look similar to us and our family members.
But there’s more to it than that. Moreso than genes and chemistry, the key factor that determines love is personality. Political inclination, education levels and personal values have consistently been shown to be crucial in forming romantic attachments. Put simply, potential partners might need attractive genes and chemistry to elicit a second glance, but it’s who they are as a person that really seals the deal.
But what about couples that seem perfect for each other but just don’t click? Contextual factors are also important to a relationship. As well as both individuals being available, willing and ready for a relationship, there are other environmental circumstances that can help.
For instance, research has shown that people form more intimate attachments if they experience an intense situation together. Whether it’s a music concert, a theme-park ride or just exploring somewhere new: adventure can be a key ingredient to the formulation of love.
It’s not all about adventure: contrary to popular belief, love at first sight doesn’t happen all that often. Most people need to spend time together before more intimate feelings can grow. In fact, only about a third of people report falling in love quickly. For most of us, this bond takes more time to emerge.
So if we do find that magic formula, then what next?
When love blooms, science can tell us a lot about how it’s manifested in our brain chemistry. Anthropologist Helen Fisher has proposed that there are three key stages of falling in love – lust, attraction and attachment. Each of these is accompanied by unique chemical and neurological responses.
The first stage, lust, is characterised by the release of the sex hormones: testosterone and oestrogen. These chemicals elicit feelings of physical longing and sexual desire for a potential partner, causing us to be more open and flirtatious. As you might expect, when it comes to lust, it’s not emotional intimacy but sex that is the primary goal.
As we move past lust and into the attraction stage, our levels of certain neurotransmitters increase, creating feelings of euphoria, longing and obsession.
Dopamine is known as a ‘happy hormone’ because it produces feelings of joy. But this chemical is also associated with profound desire, bordering on addiction. In fact, it’s also linked to cravings like junk food and drugs.
The release of dopamine’s partner in crime, norepinephrine, compounds feelings of fixation, whilst increased adrenaline is linked with our stress-response and feelings of fight or flight – hence the beating heart, rapid breathing and butterflies.
As these neurotransmitters increase, our serotonin levels go down. Serotonin plays a role in sleep, appetite, memory and mood, so when it decreases we get ‘love-sick’. In fact, the levels of serotonin levels in people at this stage of love are similar to those with obsessive-compulsive disorder (OCD).
And so we come to profoundly crave the object of our desire, and our excitement and happiness is tinged with anxiety and desperation as we strive to bond. Depending on how you look at it, the good news is that this stage only lasts for a short time. After some months these hormones go back to normal and the madness is over.
And then comes the final stage of love – attachment. Over time, the chemical reactions taking place in our brain begin to shift resulting in higher levels of oxytocin and vasopressin: the bonding hormones.
Oxytocin is sometimes referred to as the ‘cuddle hormone’. It’s released when we hug, kiss or have sex. Oxytocin promotes feelings of deep intimacy and connection and, along with vasopressin, helps to ensure that partners remain in long-term relationships even after the initial exhilaration of the first two phases has passed.
The attachment phase is characterised by security, calm and mutual empathy. Lovers feel comfortable and connected – in fact, the chemical reactions taking place in their brains closely resemble those associated with other close relationships, like love for dear friends or family.
So there you have it: the science behind why and how we fall in love. It’s clear that chemistry, psychology and neurology all play an important role, but love is not a simple formula. Science can tell us a great deal about the physical and mental reasons behind romance, but as for what love means on a deeper level, that remains a mystery best left to the poets.