An interesting interview on oxytocin and how it may affect our moral impulses.  - Dallas

The biochemistry of love and empathy

In his latest book The Moral Molecule, neuroeconomist Paul Zak describes oxytocin’s role in trust, bonding and even virtuous behaviour. New Scientistcaught up with him about avoiding the term “the cuddle chemical” and trying not to make a bride faint on her wedding day.

Why study moral behaviour?

Before my mother was my mother she was a nun, so morality was something that was very present. We had very clear top-down guidance: “you do this and you go to heaven, you do that and you go to hell”. Even as a child I felt that that was incredibly harsh and wrong. The idea that there’s some perfect received wisdom to tell the difference between right and wrong just didn’t make any sense to me. I wanted to find a concrete, biological basis for good and bad behaviour in humans.

It’s not my place to say whether God exists or not, but it seemed like there were all kinds of good people who weren’t raised Catholic like I was. And that seemed like a deep mystery about life: if there are 2000 religions, why do we see a large number of those having the same kind of prescriptions for what constitutes good behaviour and a good life? That was the deeper, personal reason that, in retrospect, drove ten years of hard labour in the lab and in the field.

What got you interested in oxytocin?

I had done work in the late 1990s showing that countries in which levels of interpersonal trust were high were richer countries, and countries that were poor were by and large low trust countries.

Having done that, the next logical question was: for a given country, why would you ever trust a stranger? Across biology, psychology, economics, and neuroscience, no one really had an answer.

When I started searching the literature for possible mechanisms for why we might want to trust strangers, I came across animal research on oxytocin that suggested the molecule allowed group-living animals to tolerate their burrow mates. I thought tolerating others and trusting others may lie on a continuum. So I found this target in the brain that had been largely ignored. There’s no medical condition associated with too much or too little oxytocin, other than preterm labour. At the time, oxytocin was thought just to be a drug used in labour, and no one really studied it. It was just sort of sitting on the shelf.

How is oxytocin involved in human trust?

In our research, we were able to show that when we’re trusting other people, our brains release oxytocin. Moreover, when we manipulate oxytocin pharmacologically we can induce people to trust others really readily, without affecting their cognition or memory.

How do you get from trust to morality?

I thought: “Gee, trust is kind of a social glue that keeps society together. The other kind of social glue is good behaviours that people engage in, even when no one’s watching, such as giving to charity. If oxytocin makes people trusting, would it make them generous? Would it make them kind? Would it make them caring?” And so we began knocking out all the virtuous behaviours we could think of in the laboratory and in the field and just seeing if oxytocin was associated with them. And by and large we found that the vast majority of virtuous behaviours and moral behaviours were linked to oxytocin blood levels. [continue]