By: Matthew Greenacre


Maybe you met that person in one of your classes, or at a house party, or you might even have met them at TwelvEighty. Regardless, now they are at the back of your mind jumping up and down as you try to read your French literature or solve Maxwell’s equations. But why? What happened in your brain that caused your usually fervent focus on your GPA, the OUA finals, or your band’s next gig, to be replaced with rosy coloured thoughts of someone who is still a relative stranger (albeit a ridiculously good looking one)?

When they first walked up to you and asked to buy you a drink, you said yes partially because a free drink is a free drink, but mostly because within about 200 milliseconds your brain decided that it liked what it saw, heard and/or smelt (though still controversial, research from Heinrich Heine University of Dusseldorf and Duquesne University has suggested that humans may use a cocktail of pheromones to communicate on a subconscious level). Norepinephrine, the trigger to the fight or flight response is released, and you feel your palms become sweaty, your heart begins to race, your pupils dilate. At the same time your reward system is activated, dopamine is released, and you begin to feel a rush of euphoria. Parts of the cerebral cortex that you use to be logical are deactivated. You are suddenly likely to do something very stupid…

Of course, we are more than our animal instincts, and it might have been the tone of their voice that you found sexy or the wit and charm of their conversation compelling. Regardless, your brain has begun to make a connection between this person and the reward system of the brain. Whenever you are intimate with someone, your brain is flooded with either oxytocin if you are female, or vasopressin if you are male. This hormone rewires your brain’s reward system so that, according to the research of Helen Fisher at Rutgers University, the ventral tegmental area of your brain now makes and releases dopamine whenever you are around your crush or merely even think about them. Now you are really up a creek because this is essentially the same flood of dopamine, producing the same type of feelings, as if you were taking cocaine. You’re hooked.

But being in love is great. Hand-in-hand you can happily skip through fields of posies in giddy dopamine soaked bliss because the hormone cortisol that makes you stressed is lowered and suppressed by oxytocin/vasopressin so even the thought of that midterm the next day barely bothers you at all. You can stub your toe and barely feel a thing because reward centres being in overdrive affects the parts of the brain that control pain. At the same time the amount of a neurotransmitter called serotonin drops. Low serotonin is common in people with obsessive-compulsive disorder, and this is why you can’t stop thinking about him or her. Your brain chemistry has primed you to obsess over things in general, and you get instant rewards for thinking about your special someone.

Just like your relationship, your brain chemistry can have different outcomes. If not enough oxytocin/vasopressin is released, your partner will not be wired to your reward system, being with him or her will release less and less dopamine and the passion you once felt will fizzle out. If enough oxytocin/vasopressin was released in your brain then I sincerely hope enough was released in his or hers.

Heart-break is the very real perception of pain that a person gets once they are cut off from their loved one. Stress inducing hormones called cortisol releasing factors (CRF’s) build up in the brain during the relationship. Once the break-up happens and oxytocin/vasopressin is no longer being released, CRF is free to produce a wave of cortisol. You become hugely stressed. High levels of cortisol are linked to depression. Your obsession does disappear, but amplifies as you try and figure out how to win your beloved back. The high cortisol and low serotonin levels give you insomnia, leaving you to lie awake, churning over your loss. You are suffering from withdrawal, trying to figure out how you can get your fix again.

With time your brain chemistry will return to its normal levels, and sooner or later he or she will just be somebody you used to know. But in the mean time we know that it is a hell of a lot of cortisol to cope with and SHEC would love to help you out if you want to drop by.

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