Connie Orbach, The Naked Scientists
Love is often considered the core force behind keeping couples together, but what is it? Is it simply some chemicals in your brain, or and how can we go about studying it? Naked Scientist Connie Orbach joined Khalil Thirlaway to explain what science can tell us about love...
Connie - It can tell us an awful lot and not much at all, all at the same time, it would seem. There seems to be three stages; so weíve got the lust stage which I think youíve already been talking about on the show. Itís the stage of attraction where you may be quite promiscuous, thereís really high testosterone levels in males as well as females.
So after that we have the attraction stage and thatís when the real high kicks in. Itís kind of the honeymoon period and you see really high levels of whatís called monoamines at that point, which are chemicals in the brain. Youíve got serotonin, dopamine also noradrenaline - these are all the kinds of things which give you a massive high and just make that period just absolutely amazing.
And finally, we have the attachment stage which is the bit which makes you want to stay together.
Khalil - So at this point in a relationship, whatís going on in the brain and body chemistry?
Connie - Okay. So thereís a few different things going on and itís interesting that we say - love, itís all about chemistry because, actually, a lot of the time it is. Weíve got huge changes in the chemical balances in our brain that happen around this time. Thereís a few different really important hormones involved; weíve got oxytocin which you may have heard of before - itís often called cuddling chemical. Itís the kind of thing that makes social bonding and social cohesion work; without it weíre not very good in social situations. Weíve also got vasopressin which is actually controlling heart rate and things like that, but weíve seen itís really important in monogamous animals. And when weíve studied this, weíve actually used an animal to study it - the Prairie vole, and theyíre really cute little voles and what we find is that they actually nest together. They stay together for life once theyíve got a partner and they bring up their children together, so theyíre kind of one of the best analogies that we have for humans. Whatís also really useful with them is that thereís a different type of vole, the Montane vole, which is really closely related but not monogamous. So when weíre looking at differences in the brains, we can compare the two and get a better idea of whatís going on.
Now with these voles, if we knock out their ability to respond to the hormone I just mentioned, vasopressin, they actually canít form a monogamous bond - they donít stay together. But, thereís also something else which I find really interesting which is that dopamine gets involved here. Now dopamine you might have heard of specifically with drug addiction and thereís a reward pathway in the brain which is activated with dopamine. Now what we found in the Prairie voles is that before sex and after sex, dopamine can have a really different action. Before sex, itís causing these Prairie voles to go out and be really promiscuous and find mates, and you know get out and meet people like weíre always needing to do, or meet tiny little voles, I guess. And after sex, itís actually causing them to be aggressive to other animals that are the same sex to them. They essentially become jealous, possessive, Prairie voles. The kind of thing that is the epitome of that horrible thing that happens in a relationship to your other half.
Khalil - I guess this one bit of the animal kingdom we donít quite want to emulate?
Connie - Yes, definitely!
Khalil - This idea of mating affecting your dopamine levels and almost making these voles addicted to their mate - kind of sounds like a drug?
Connie - Yes, it does. And, I mean, Iím sure thereís loads of songs talking about love as a drug. Itís hard to say that itís addictive because thereís lots and lots of different things that set off the dopamine reward system and not all of them are addictive. We have so many different myths thrown around like, chocolate's addictive. And they may activate that pathway but thereís a few other things that need to happen for something to be addictive, but it definitely gives you that high that addictive substances give you.