INTERVIEW WITH PROFESSOR LAUREN STEWART
Lauren Stewart, is a 30-something Professor in Psychology at Goldsmiths, where she leads the Music, Mind and Brain group.
An amateur clarinettist, she’s shyer than Dolan, and less used, I suspect, to addressing a general audience. But she clearly knows her subject and arrives with both her instrument case and a laptop, which she uses throughout our conversation to find references and illustrations.
Almost her opening words are ‘the big thing is plasticity’, which is an encouraging message for middle-aged amateur pianists. ‘We used to think that people who’ve get special skills had different brains to start off with. Now we know that that’s not the case. It’s the other way round – learning these special skills actually gives you a different kind of brain. It sculpts the brain in particular ways that you need.’
As an example, she talks about the brains of violinists, who have been shown to develop a larger area of somatosensory cortex, particularly in the right lobe. This makes sense. As Dolan explained, geographical representa- tion in the brain is ‘flipped’: the right lobe represents the left of the body, the left lobe the right. A violinist’s left hand does the more complex job of stopping on the instrument, whereas the right hand merely holds the bow – hence the violinist’s asymmetry – a big bulge on the right. Pianists, who engage both hands in equal measure, have more of a ‘bilateral bulge’. I wonder about the size of this ‘musical bulge’. Is it visible with a microscope? Stewart says it’s much bigger than that. On an MRI scan you can pick up the differences with the naked eye.
I wonder if these developments took years, and if it was crucial that you started learning before the age of 7, say? Not at all, according to Stewart. The change can be rapid, occurring over the course of just a few weeks, even. She tells me there have been arguments that if you don’t begin learning before an early age, you’ll never have perfect pitch, but she thinks perfect pitch is ‘over-hyped’ in any case, and that most musicians don’t really want it. But no, learning from an early age isn’t necessary in allowing these neurological developments.
Stewart goes over some of the same territory as Dolan, explaining about neurons, axons and dendrax. I get her to show me the areas of the brain on a medical illustration of grey matter I’ve downloaded from the web. She talks excitedly about all the recent research which shows what’s going on inside the brain when music is being created. We look at the corpus callosum, the flat bundle of neurons that connects the two hemispheres of the brain. ‘The research has shown that in musicians the corpus callosum is enlarged, not throughout, but just in the large anterior portion, so probably this bit’ – she points to an area of the brain on my illustration. ‘They think this is probably due to the requirement that musicians have to essentially coordinate between their hands and their feet. Again, that is something that is sculpted through intense training.’
We then move on to talk about the work she’d done for her PhD, which has originally involved trying to find people who were illiterate and then scanning them progressively using functional MRI as they learned to read. By giving them the same set of word stimuli over time and comparing how the brain’s response changed, she would be able to see which brain areas or networks of brain areas were being altered through learning. ‘But we couldn’t find these people because they don’t really exist – everybody has got a certain level of literacy and, if they haven’t, there’s normally a good reason why they haven’t. So I said: “Well, why don’t we look at people who are musically illiterate because there’s definitely loads of them and I would be able to teach people to read music and play the piano in a way that I wouldn’t really be able to teach people how to read language.”’ So she recruited fifteen adults who had never read music or played an instrument but who were really keen to do so, bought a set of Casio keyboards and then, every week, she would teach them in groups of four to read music and to play keyboard. She taught them music theory as well and, after three months, they reached Grade 1 standard. By this stage they could play with two hands and manage basic things such as scales.
‘The important thing was that we scanned them both before and after the training and we also scanned a group of similar people before and after. These control people had never read music but also didn’t learn it either so that was a control.’
Stewart discovered two particularly interesting things. The first was that she saw changes in the superior parietal lobe. ‘This is an area that’s involved in spatial transformations, when you have to plan your actions based on the position of something in space. I always think of playing tennis, you are actually planning the trajectory of the ball and you have to think, “Right, where do I need to be?” so you have to use spatial coordinates to plan your actions. That’s really what you’re doing if you’re a pianist. If we just think about pitch, because of pitch being organised vertically and the keyboard being organised horizontally, you’re pretty much doing a spatial rotation.’
The second insight related to an area of the brain called the supramarginal gyrus. ‘This area has been associated with intention to act.’ What this suggested to Stewart was that once you’ve become an expert in decoding musical notation, even if you’re, relatively speaking, a novice, you automatically prepare to act when you see that notation, ‘even when you’re told not to’. ‘In fact,’ she says, ‘you have to inhibit the learned action.’
She talks a little more about the technicalities of her work, and I begin to get lost. I try to drag things back down to my level, and ask if she’s learned any basic principles as to how memory works in relation to music. She tells me about the concept of ‘chunking’. ‘Think of people who can remember pi to hundreds or thousands of decimal places: it just seems like a superhuman feat. You think, “Well, these must be very unusual people.” But they have a special trick to do it, which is that they essentially break a very long number up. Instead of, for instance, having to remember a hundred individual items, they might break that into ten items of ten where those ten – that is, the composition of one chunk of ten items – is meaningful to them. Chess grandmasters can do this very, very well. Perfectly, in fact.’
This ‘chunking’ is applied by the brain in music reading, especially when you’re first trying to make sense of a piece of music. ‘You’ve got two staves and there might be several notes per stave. So the way you do that is by thinking, “Well, that’s a chord of C major and that moves to F major and there’s an arpeggio.” So you can turn something that looks like a whole bundle of confusing notes into a meaningful digested thing by drawing on your knowledge of music and also by using what we call “top-down expec- tations” about what’s going to come next.’
This sounds very similar to Ray Dolan’s concept of the brain working on a principle of prediction. Indeed, Stewart tells me ‘there have been studies where you get people to sight-read a piece of piano music and then you whip the music away from them at a particular point and you see how many more notes they can bang out that are correct. Some people are really good sight-readers and that means that they are looking further ahead and planning further ahead. That kind of thing happens also if you’re doing touch-typing if you’re transcribing from a written text you’re planning well ahead of where you actually are.’ So as a good sight-reader, I must be a good ‘chunker’. But am I going to be able to use this ability to learn the Ballade note by note?
Stewart finishes by talking about what happens ‘when plasticity goes bad’. The result is focal dystonia, in which misfiring neurons cause involuntary muscle contractions. ‘When you’re learning you might get cortical expansion of the territory. Well, if you get too much of that you start to lose the
individual representation of each digit, so that you can no longer exercise them independently, which is a disaster for any high-level musician.’ But this also seems to involve personality factors like anxiety and stress, she says. She tells me the story of the pianist Leon Fleisher, who developed focal dystonia just as he was about to become a total star. For many years he couldn’t play with both hands. ‘But he relearned, he went to see a neurol- ogist. They managed to rehabilitate him.’
Thumbnail image credit: http://www.gold.ac.uk/psychology/staff/stewart/
BUY THE BOOK
Available in hardback and enhanced e-book format.
Download the digital accompaniment to the book: Interactive ibook 'Know the score'