Sunday, October 12, 2008

Oxytocin, music of love

Oct 11, 2008
DAEDALUS: TECHNOLOGICAL TRIUMPHS & CHALLENGES

By Andy Ho
THE Home Ministry is looking for face recognition software to use with its surveillance footage. After it was discussed here last Saturday, a reader asked if such software might help her autistic child.

Such parents are, commendably, always looking for solutions for their kids who generally don't like to look at faces. Autistic children tend to avoid eye contact, have limited facial expression themselves and are usually socially withdrawn.

Since perception of faces is a very basic component of social interaction, the brains of the autistic may well have problems processing faces. In 2000, special MRI scans confirmed this to be the case.

We tend to remember and recognise faces more easily than we do names. This is because there is a specific part of the brain as small as a pea that responds to human faces twice as strongly as it does to non-face objects - like cars, cats, cows and so on. This spindle-shaped site, called the fusiform face area (FFA), is located halfway back in the head, at the bottom of the part of our grey matter that interprets visual images.

The FFA enables us to assess a person's sex, age, mood, intentions, sincerity and so on within seconds of contemplating his or her face. In cases where the part of the brain the FFA is now known to be located has been injured, patients may develop 'face blindness'. Such patients can recognise a face as a face - as distinct from non-face objects - but cannot identify individual faces any more. So they can't grasp why robbers in movies would use face masks.

In normal people, the sight of faces stirs up not just the FFA but also certain parts of the brain it is connected to. These parts are involved in language, memory, attention and emotions (the last being specifically called the limbic system). These distributed neural networks connected to the FFA are involved in processing the complex social meanings that facial expressions convey and communicate.

Unlike those with face blindness, however, autistic kids can discriminate among the faces of people they meet every day. It is now known that, in autism, the FFA and its extended neural circuitry are activated to a lesser degree than in normal people. Thus, when the autistic person sees a face, fewer memories or emotional cues are evoked. He or she processes faces more like objects than socially significant countenances.

Because this network of 'social' neurons does not work as smoothly in them as it does in normal people, autistics tend to be socially awkward. Perhaps, a nectar of serenity, bonding and love, if one exists, is what autistic children need?

There is, in fact, such a nectar - or a hormone, to be precise - one that is the very antithesis of adrenaline, the hormone of excitement and aggression. That love chemical is called oxytocin. It surges in the brain post-orgasm, initiates womb contractions that lead to child birth, and triggers milk production in mothers.

Oxytocin also lowers the blood pressure and feelings of stress while making one feel sociable and lovey-dovey. Some clubbers resort to Ecstasy, the cuddle chemical that increases feelings of generosity and intimacy towards others. In rats, Ecstasy causes a brain surge of oxytocin just as it does after orgasm.

Post-orgasmic human males feel sensual, not sexual. They feel really good about the person they are with. Even rats given Ecstasy tend to stick close to one another to 'chill out'.

In 2003, University of Stockholm scientists discovered that people who sing together release more oxytocin in their brains, which may lead to 'limbic resonance'. When the emotion processing network called the limbic system (which is linked to the FFA) resonates among people, they become attuned to one another's feelings. Then they sing in harmony, feel similarly aroused, and think they are truly at one with others. Perhaps that is why church services have always included congregational singing.

There is interdisciplinary interest in this link, like yesterday's conference at Arizona State University on 'Oxytocin and Music'. When people sing or listen to music, the brain releases more oxytocin. This may be why music fans feel so connected to their idols, argues Professor Daniel Levitin - a former rock musician himself and now a neuroscientist at McGill University in Canada.

In his recent book, The World In Six Songs: How The Musical Brain Created Human Nature, Prof Levitin argues that all music talks about one or more of six things. These are friendship, joy, comfort, knowledge, religion and love - all of which have to do with human emotions. The link between them is that music releases oxytocin. Perhaps that is why music therapy does help autistic children.

So oxytocin, not face recognition software, might help these kids. Last year, it was reported that autistics who were administered oxytocin seemed to do much better. There is, in fact, an ongoing US trial in this connection.

In deploying any hormone therapeutically, however, one must be aware that it has a normal level that the body maintains in fine balance with the normal levels of other hormones too. We don't know yet how boosting oxytocin levels might cause other hormones to go out of whack. It could also cause the body itself to stop producing oxytocin naturally.

So parents of autistic children should wait to see how the US study goes. But since music may well be the food of love, play on.

andyho@sph.com.sg

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