• Sex on the brain

    Sex on the brain

    Think you’re in charge of your love and sex life? Think again. When we call people ‘love junkies’, we are actually being accurate: we’re all completely and utterly under the influence of our brain hormones.

    Logic and sensibility don’t stand a chance against the army of sex and love chemicals, hormones and neurotransmitters released during attraction, lust and love by our brain. And they’re as volatile and argumentative as they are potent, each jostling with the other for control at every stage.

    Is it any wonder the path of true love doesn’t run smoothly with this lot at the controls! If you want even half a chance of lasting the distance as a couple, you need to arm yourself with these neurological facts. At the very least you can anticipate what you’re in for!

    The three phases of love and sex


    What’s happening: You see, you want. And what you want is usually symmetrical, young and healthy. Men are programmed to look for fertile women (small waist, curvy hips) women are programmed to seek good providers (big wallet, sports car). Fifty per cent of our brain is dedicated to vision, which is why looks are so important initially.

    The chemical cocktail:

    • Testosterone is mainly produced by his testicles but her ovaries also create a small amount. It’s responsible for sex drive. Estrogen is produced primarily in her ovaries but both his and her brain also manufactures it. It regulates the menstrual cycle but also helps maintain a healthy, lubricated vagina.
    • Nitric oxide is a chemical released by our genitals when we’re aroused. This is what causes blood vessels to dilate, allowing more blood to pump through to crucial parts - like his penis. Viagra and Cialis work by simulating the release of nitric oxide.
    • Pheromones are scented hormones secreted by our sweat glands, chiefly under our arms. We’ve all heard of pheromones but researchers are still pondering exactly how they work. What is clear is that they’re crucial in deciding who we want to get horizontal with and who we don’t. The scent they emit is vital: numerous experiments have shown if someone doesn’t smell good to us, we won’t go there. In fact, just as some scientists argue our brain is our true sexual organ, there are others that swear it’s our nose. Love at first sniff.

    Potential problems: None, if you’re both single and attracted to each other. Huge, if one or both of you are involved with someone else. This mix of chemicals and hormones is potent with a capital P. Caught in the grips of it, like a rabbit caught in headlights, thoughts of the long-term consequences caused by acting on desire are obliterated. Look away, move away, hit yourself over the head with a heavy object - just do whatever it takes to break the spell.


    What’s happening: You got what you wanted and have embarked on some kind of relationship. This is the ‘honeymoon’ period, the ‘in love’ dippy, swoony bit. The part where you can’t think of anything but the person you’ve just met. If they dropped on one knee and asked you to elope in the first two weeks you’d say yes. You’re either manically happy when they show your feelings are reciprocated or in total, abject despair if they call five minutes later than they promised to. The word ‘obsessive’ hardly begins to describe how often they pop into your head.

    The chemical cocktail:

    • Epinephrine and norepinephrine are neurotransmitters produced in the adrenal glands, spinal chord and brain. They’re called ‘excitatory neurotransmitters’ because that’s exactly what they do: create tummy-flip-flops, a fast-beating heart and an adrenaline rush of excitement. This keeps us aroused and also helps push us over the edge into orgasm.
    • Dopamine is the undisputed star of all the neurotransmitters associated with infatuation because it controls the big three: pleasure, motivation and concentration. It’s the boss of the ‘reward centre’ of our brain, giving us a kick up the bottom to seek out pleasure and making sure we enjoy it when we do by focusing on the task at hand.
    • Serotonin is the ‘feel good’ neurotransmitter produced in the mid brain. It controls our mood and emotions and particularly how flexible we are in our thinking. Bizarrely, considering it’s nicknamed the ‘happy chemical’, we’ll often have low levels of it when first in love. This is why euphoria is punctuated with feeling moody and anxious.
    • PEA (phenylethylamine) acts a bit like adrenaline by speeding up the flow of information between nerve cells, ensuring we pay attention to all the ‘love’ feelings ricocheting wildly around our heads. PEA gives the nod for chemicals to flood into the brain, creating feelings of euphoria.

    Potential problems: Dopamine and serotonin battle during infatuation because the higher the level of dopamine, the lower the level of serotonin. They can’t co-exist at the same level. This means in one corner, we have dopamine trying desperately to make us behave in a way that’s loveable; in the other corner, low serotonin - forcing us to make bad judgement calls because of obsessive thinking - does it’s best to make us unlikeable. PEA can play havoc if you’re already attached and someone other than your partner has you quivering with pleasure. It makes us impulsive - and prone to shag first, think (about losing the wife/husband/kids/house) later. Too late type of later.


    What’s happening: If you’ve managed to survive the emotional rollercoaster that is infatuation, you’ll move into the ‘true love’ stage. It’s calmer and less crazed than the other two but this doesn’t mean it’s any less intense. This is when you feel a sense of connection, a quiet happiness and feel at peace with the world. It’s also the time when sexual desire also puts its feet up and kicks back. Who can be bothered having sex when you’re quite content snuggling on the sofa watching telly with a takeaway?

    The chemical cocktail:

    • Oxytocin is released by the pituitary gland and acts on the ovaries and testes to regulate reproduction. More importantly, it’s the bonding, ‘cuddle’ chemical. When you hold hands or hug the person you love, oxytocin levels soar along with your heart. Our levels shoot up during sex, peaking at orgasm but his catapult to a level more than 500% than usual after one! Considering this is also the hormone released during breastfeeding, designed to make babies sleep afterward, this could explain why men want to nod off when women have just got going. Oxytocin also has an amnesic effect during sex and orgasm in that it blocks negative memories people have about each other. Yet another reason why couples that have lots of sex actually like each other more. High oxytocin levels are also associated with trust. What’s not to like about this one?
    • Vasopressin is found in higher levels in his brain than hers - which isn’t surprising since it’s in charge of ‘male’ behaviours like dominance, sexual persistence, and territorial feelings. It’s also lovey dovey and releases when he’s in lurve.

    Potential problems: Again, differing hormone levels can create havoc. Once there are high levels of oxytocin and vasopressin, dopamine and norepinephrine pathways are compromised. So infatuation bids a sad farewell as attachment increases. The relationship feels less exciting because of it. Even worse, while elevated levels of vasopressin in men makes him feel all fuzzy, protective and loving, the spin-off is a suffering sex drive. The more in love he is, the more vasopressin there is in his system, which causes levels of testosterone (which make him feel like sex) reduce. In plain English, the more attached he feels, the less likely he is to want to shag you senseless. Brilliant.

    Trick your brain

    • Forget everything you’ve been told. ‘Trust, familiarity, predictability, romance - are not the building blocks of desire’, says US sex therapist Ian Kerner. His solution: have a place in your life that’s just for sex. It might be a certain time, certain place, certain state of mind. Work out what puts you both into ‘sex mode’ and use the triggers.
    • Be a thrill seeker. Novelty is what tricks the brain into producing the hormones it did at the start. Take away spontaneity and surprise and you strip the relationship of lust. Push yourselves out of your comfort zones, rather than stay where you feel safe. Feed your fantasies. Be naughty. Think edgy.
    • Don’t live in each other’s pockets. Long-distance relationships are often more passionate than lovers that live together day in, day out. Why? If you have sex with and see your partner all the time, there’s no need for dopamine because you don’t have to work hard to get a reward. Being separated, even for short periods, makes our brain sit up and pay attention.
    • There’s an argument for arguing. Make-up sex is hot because anger stimulates the production of adrenaline, which in turn produces dopamine. A huge row also puts the relationship at risk, making us appreciate the person we almost lost.
    • Do special things - but now and then, rather than all the time. The brain likes to be kept on its toes. Relaxation equals complacency.
    • Look after your brain. Limit toxins like alcohol, drink tons of water, get enough sleep, eat well, take vitamins.

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