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The Biology of Love and The Four Stages of Attraction.

You’d think that after hundreds of thousands of years of evolution, we would have adapted beyond our basic primal instincts. It turns out, that these innate urges have stayed with us almost unchanged as inbuilt processes within the oldest regions of our brains.




It’s hard to know which part of us is in the driving seat when it comes to lust. Our attraction to someone initiates a cascade of hormones which in turn, reinforces our attraction. Nothing short of extreme will power is required to overcome such a potent biochemical force.

There are several regions and chemicals at play in this tsunami of emotions, the most powerful among them, in my view, being the so called ‘love hormone’, oxytocin. This neuro-peptide is involved in multiple behaviour patterns from tickling our pleasure centres during sex, to forging mother-baby bonds with infants.

A recent study from the Weizmann Institute of Science suggests that it is also responsible for negative behaviour. This neuro-modulator activates specific neural pathways according to the environmental conditions in which a subject finds themselves.

In a harmonious and loving relationship, oxytocin can reinforce the feelings of closeness and loyalty, but under quarantine conditions with limited space or food, the same chemical can trigger belligerence and aggression. Which way a person reacts to these changing circumstances is largely down to our underlying personalities and upbringing. Some might be content with a minor row to clear the air while others result in divorce or worse.

Just being aware of these causal links should be enough to help regulate the ‘dose’ of neuro-modulating chemicals we release into our bloodstreams. Paying attention to the sensations arising from interacting with others should enable us to modulate our reactions, thus down-regulating negative peptides and up-regulating those which make us feel happy and content.

Dopamine — the feel-good chemical

Back in 2005, a team of researchers led by Fisher, analysed the brains of individuals in the throes of romantic love. Her team scanned 2500 college students who each viewed images of people they had declared as special to them. The team discovered that two brain regions associated with reward detection, integrating sense data, pleasure, focused attention, and motivation were highly stimulated when they saw pictures of people they loved.



One of these brain circuits, in the ventral tegmental region, is considered to be a primitive neural network that has barely evolved in thousands of years. Some of the other areas it links to as part of the reward circuit, the amygdala, the hippocampus, and the prefrontal cortex, are extremely sensitive to behaviours that induce pleasure, such as sex, food consumption and drug use, thus encouraging us to seek more. As a result, we can easily become addicted to the ‘highs’ associated with these behaviours.

The four stages of love — stage one

When we fall in love, our bodies are flooded with an entire cocktail of chemicals. A dizzying array of pleasure hormones and neuropeptides reduces us to blushing, anxious, sweaty fools with racing hearts and dry mouths. We don’t know whether we’re having a panic attack or verging on ecstasy.

The stress of this increases our cortisol levels, depleting our supply of serotonin. This is what gives rise to those infuriating obsessive thoughts about our new paramour; the hopes, the fears, and the reliving of intimate encounters that plague our every waking moment.

Stage two

The state of being love-struck enters a second phase when high levels of dopamine kicks in. Our reward centres are activated, giving us that perpetual euphoria similar to an alcohol induced haze. This is backed by a 2012 study conducted at the University of California. It stated that male fruit flies that were sexually rejected drank four times as much alcohol as flies that mated with females. According to Richard Schwartz, Professor at Harvard Medical School, it was the ‘Same reward centre, different way to get there.”

Stage three

As we reach the stage when things get physical, oxytocin and vasopressin have their moment. These are released during sex and heightened by skin to skin contact. Oxytocin enhances feelings of closeness and attachment, contentment and security. It’s often associated with mate bonding.

While the ‘love hormone’ keeps reigniting passions in the early phases of a relationship, it can be replaced by increasing levels of vasopressin. This chemical is linked to long-term monogamy and explains why attachment grows as passion fades.

It’s interesting to note that these love cocktails can also have the effect of deactivating behavioural pathways that might otherwise prevent us from acting on urges, such as fear and social judgement. In other words, we biochemically mute our common sense over choices of partners. As Schwartz puts it; “That’s the neural basis for the ancient wisdom ‘love is blind’.”

Stage four

Assuming that a relationship makes it past stages 1–3, we reach the calm resignation of attachment; “The passion is still there, but the stress of it has gone,” says Schwartz, who incidentally has been married to his colleague, Jacqueline Olds for four decades.

Our cortisol and serotonin levels return to normal, we still crave pleasure and reward, but the obsessive behaviour declines. Schwartz and Olds claim that there is an inevitable change over time from compulsive, passionate love into a more mellow compassionate form. It might be less euphoric than the early stages but it doesn’t necessarily mean the relationship has lost its spark.

Forever love

In 2011, a New York State team of researchers at Stony Brook University scanned couples who had been married for more than twenty years. Despite being firmly set in their ways, their brains lit up with activity in the exact same way as newly-in-love couples.



Those whose closeness and intimacy had fallen by the wayside found it could be reignited with a little effort. One small alteration in sexual activity flooded their body anew with oxytocin thus stimulating the reward centres and refuelling their desires for each other.

Let this be a lesson to us all when these stressful events are over. Before rushing to the divorce lawyers or dividing up the book collection, maybe we should accept that these are unusual times. A relationship might just need a kick-start to renew the neuropeptides and send us all into the next decade of happiness instead.


Stay safe all.

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