Love really is blind...
Neuroscience can at last explain why we can't see faults in our partners or children. Raj Persaud reports
Can science help us to understand love? Many argue that a Shakespearean Sonnet, Rachmaninov piano sonata or Jane Austen novel is much better at communicating insights into why we become irresistibly drawn to one person. But now neuroscience promises to offer revealing new insights that could solve some of the mysteries at the heart of love.
A study of whether there are different forms of love has been launched by Dr Andreas Bartels and Prof Semir Zeki from the Wellcome Department of Neuroimaging at University College London. They have attempted to unravel for the first time whether the love between a parent and a child is the same as the emotion shared by lovers and whether all forms of intense attachments are basic variations on the same theme.
Scientists have a cold eyed view of the purpose of love. The tender intimacy and selflessness of a mother's love might be celebrated by inspiring music, literature and art. Many great artists have been profoundly affected by the relationship between mother and child, as depicted by Da Vinci's Virgin and Child, Van Gogh's First Steps and so on.
But the evolutionary biologist has a more prosaic formulation – the lifelong commitment serves to help a parents' genetic material survive through to future generations. The passion shared by two lovers serves a surprisingly similar function – it facilitates mating and parenting – and hence again is merely the selfish gene in action. If we didn't love, then the species would simply never get perpetuated, so maybe that is love's actual function.
But if all love boils down to, according to science, a genetic prerogative being pursued through hard wiring in our brains, then the neurological basis of love, like the brain activity and hormonal responses which underpin love, should theoretically share similar biological underpinnings.
To investigate this question Bartels and Zeki, who have a long running programme investigating love using the very latest brain imaging techniques, measured brain activity in 22 mothers who viewed pictures of their own infants and compared this with activity evoked by viewing pictures of other infants with whom they were acquainted for the same period. In addition they compared this activity to that when other volunteers viewed their partner, a best friend and an adult acquaintance to further control for familiarity and friendly feelings.
The design of the experiment, using functional Magnetic Resonance Imaging, and just published in the journal Neuroimage, allowed the scientists to determine the brain activation related to maternal and romantic love while at the same time controlling for the effects of familiarity and merely friendly feelings.
The first intriguing finding is that there is a lot of overlap between the brain areas activated during feelings of romantic love for a partner, and those involved in maternal love for own children. The brain cells implicated are the same as those we know become active whenever an extremely rewarding activity is being undertaken. These are precisely the same neurological locations which are implicated when we consume food and drink we like, take drugs like cocaine, and when we are given monetary rewards. So love is indeed like a drug.
However the key result was that it's not just that certain shared areas of the brain are reliably activated in both romantic and maternal love, but also particular locations are deactivated and it's the deactivation which is perhaps most revealing about love.
Among other areas, parts of the pre-frontal cortex – a bit of the brain towards the front and implicated in social judgment – seems to get switched off when we are in love and when we love our children, as do areas linked with the experience of negative emotions such as aggression and fear as well as planning. The parts of the brain deactivated form a network which are implicated in the evaluation of trustworthiness of others and basically critical social assessment.
In other words, strong emotional ties to another person inhibit not only negative emotions but also affect the brain circuits involved in making social judgments about that person. The results, conclude Bartels and Zeki, suggest that attachment involves a push and a pull mechanism – you are pulled along by the strong sense of reward you feel when you love. But you are also pushed by a tendency not to objectively see faults in the other person which might threaten love, or put the brakes on, so preventing you rushing headlong into a relationship, because circuits responsible for critical social assessment and negative emotions are literally switched off. So love really is blind and there is a biological basis for the blindness.
This is a profound finding in the history of our attempts to understand this most profound and powerful human emotion. It means neuroscience finally explains a puzzle that has flummoxed artists from Shakespeare to Sinatra attempting to interpret love, which is why we can't see the faults in our partners or children which others can clearly perceive, and as a result find our affection mysterious. It also explains why we take so long to finally see the flaws in those we idealise because of our love, and which means we can end up choosing the wrong person to commit to.
The flaws only become apparent after our initial ardour has cooled, allowing previously suppressed brain areas to awaken to the reality of who we find ourselves with the morning after.
But another key finding from the Bartels and Zeki study is that there are important differences in the brain areas involved in parental as opposed to romantic love – so the two are not exactly the same. For example, in romantic love a part of the brain towards the base, called the hypothalamus, is specifically activated and this area is implicated in pushing out chemicals which mediate sexual arousal like testosterone and other sex hormones. The hypothalamus does not activate when we love our children.
Another difference was the part of the brain involved in face processing and recognition appeared to be more active in maternal compared with romantic love and the authors of the study speculate that the rapid rates with which the facial features of babies and young children change and the importance of reading children's facial expressions require a constant updating of the face-recognition machinery, leading to heightened activity in this part of the brain.
The fact that this face recognition area is not so active in romantic love suggests our lovers are meant to not change so rapidly in appearance, indicating perhaps a neurological basis for suggesting we were meant to be monogamous, or at least not sleep around so much that our brains might find it difficult to recognise whom we were waking up with the next morning.
Also in romantic love some parts of the brain possibly implicated in what is termed "theory of mind" seems to be more active compared with maternal love.
"Theory of mind" is about the notion that for us to communicate effectively we have to develop a good insight into what is going on in other people's minds so we don't offend, and can work out how to please, others. This finding suggests that an important part of the reward we experience when we are romantically in love comes from understanding that another is in love with us.
It is intriguing that this brain area doesn't seem to be so important in parental love as it means that knowing our children don't reciprocate our feelings for them doesn't stop us loving them. Now neuroscience is telling us that our brains dumb down and rule our hearts so we rush into sex, then produce children whom we also continue to care for no matter how little they reciprocate.
It would seem that one of love's mysteries has at last been cracked by science – if we used our brains to their full capacity all the time and didn't deactivate clear thinking and critical judgment, the species would never have got off the ground.
- Dr Raj Persaud is consultant psychiatrist at the Maudsley Hospital, Gresham Professor for Public Understanding of Psychiatry and author of From the Edge of the Couch (Bantam Press £6.99). He is discussing human emotion with Lord Winston and others at the Cheltenham Science Festival on Sunday, June 13.
- The festival runs from June 9 to June 13 and will feature many leading scientists and communicators, such as Prof Colin Pillinger, Paul Broks, Kate Humble, Piers Bizony, Prof Jim Al-Khalili, Prof Robin Dunbar, Prof Vilayanur Ramachandran, Armand Leroi, Prof Simon Baron-Cohen, Prof Colin Blakemore, Prof Keith Kendrick, Prof Richard Fortey, Sheila Kitzinger, Prof Richard Dawkins and John Gribbin. To request a brochure tel: 01242 237377. To book tickets tel 01242 227979 or visit www.cheltenhamfestivals.co.uk.
My father sent me a link to this article, saying it was in some ways a companion to the previous article: The same "what non-obvious ways do humans react to humans--and to things taking the place of humans?"
In other news, a German study claims that regular sex helps students.