Endocrinology of love

9 February 2008

Love is a tricky one. First of all, we have to bear in mind that the words we use for love are less than scientific. Like colour, we know that there is such a thing but frequently the categories we use to slice its continuum are somewhat limited. Love is the product of neurochemical changes in the brain and hormonal processes in the body, and it’s never quite the same. This does not demean love. Personally I consider New Age notions of rays of rose-coloured light insultingly oversimplified and utterly insipid. Neurology does not exactly change anything; if love is biology, it has always been the case. But perhaps acknowledging the role of our bodies might be kinder than insisting on some kind of impossible, Disney-style romance. So meet the colours of love: testosterone and oestrogen. Both sexes have them but in differing proportions, varying between individuals and with massive change over time. They make you horny. This can manifest itself as hopping around like a rabbit on crack or an obsession with updating your profile picture. They embody an individual desire for (cough, um) love. Dopamine and serotonin are feel-good hormones. They create a feeling of inspiration and achievement- but in high levels they can flip and cause nervousness and guilt. They phase in between lust and commitment. When you find someone in particular interesting and intoxicating to be around, these are the culprits. Adrenaline? It’s the pupil-dilating, heavy breathing hormone, physical exertion hormone. Moving swiftly on… Oxytocin is the imprinting hormone. It is frequently mislabelled the “monogamy hormone”. Since it is caused by everything from hugging to childbirth, and other forms of body-contact between the two, it affects love in general, not just romantic love. It causes bonding and function is a matter of degree. This is the chemical that makes you insist on calling each other pet-names. Massive rushes of it caused by certain intense physical experiences cause feelings of unity and comfort. It is chemically quite similar to amphetamines, and it’s what makes the “free hugs” movement so popular. The neurology of love should not be seen as a constraint. The fact that a significant percentage of research subjects do X, Y, or Z does not mean that you as an individual will do the same or even the opposite. So love they way you feel is right- if there are biological constraints to it you’ll find them yourself. Do a case-study or two. That is perhaps the most scientific way to go about it.