Tuesday 26 November 2013

Musical Training has Long-Lasting Effects



The other day, as I was dropping off my son at school, I was approached by another mom, who asked for my business card and said she was thinking about putting her 6-year-old daughter in piano lessons.  She told me that she’d been reading a lot in the news about how studying music was good for brain development.

I’ve noticed this too:  a flurry of news articles in the last few weeks extolling the benefits of musical training for children’s brains.  Music training altering the brain isn’t really news, but here's what is: several recent research studies show that a relatively short period of musical training early in life can have long-lasting effects on the brain.

Nina Kraus’ lab at Northwestern University has published a stack of papers showing that musical training alters the way the brain processes sound.  One of the ways they study auditory processing is by looking at the electrical responses of the brainstem in response to sounds such as speech.  One particular type of sound in speech that can be difficult to process is the transition between consonants and vowels.  Because this transition happens so quickly, it can be hard to tell apart the sound "da" from the sound "ba", for example.  A fast brainstem response to consonant-vowel transitions indicates that this type of auditory input is well-processed, and this in turn leads to enhanced language abilities.  Kraus’ lab has shown in the past that musicians’ brains have faster responses to these types of transitions than the brains of non-musicians.

A new study from Kraus’ lab, published this month in the Journal of Neuroscience, compares brainstem responses to consonant-vowel transitions in older adults who either had no musical training, a small amount of musical training (1-3 years) as a child, or a moderate amount of musical training (4-14 years) as a child.  Note that all of the musical training had occurred while the subjects were children, and so it had been roughly 50 years since these people had had music lessons.

Despite the fact that it had been so long since musical training ended, there were noticeable differences in the responses to consonant-vowel transitions in the brains of the three different groups.  The fastest responses were from the people with the most musical training, while the people with no musical training had the slowest responses.

From White-Schwoch et al. (2013).  Group average brainstem responses to the sound “da”.  The blue lines (fastest response) are the subjects with moderate musical training, orange is little musical training, and grey lines are the responses from people with no musical training.



This study shows that the effects of musical training can persist long after the musical training has stopped.  Why would this be?  We tend to think of our brain capabilities in a “use it or lose it” fashion – for example, if you don’t play the piano for 50 years, you’re probably not going to be able to play it very well.  But in this case, what the musical training did was to alter the way the brain processes sound, and since processing sound is something that we do in everyday life, the enhanced neural responses to sound continued to be used after the end of musical training.  The authors of this study suggest that early musical training primes the brain’s auditory system for further plasticity in response to sound, setting the stage for future auditory effects on the brain.

Another study, presented at the recent annual meeting of the Society for Neuroscience, showed that people who had musical training that started before the age of seven had thicker gray matter in certain areas of the brain than those who started musical training later.  This research, authored by Yunxin Wang at Beijing Normal University, indicates that starting lessons before the age of seven is more likely to lead to long-lasting brain changes, something that has been suggested by previous research.  What is slightly different about Wang’s study, though, is that the subjects were not all currently musicians; some had had only a small amount of musical training in childhood and not continued with lessons.  Nevertheless, that early musical training seems to have left an impression in their brains.  Whether the differences in brain anatomy lead to any change in brain function is not yet known, but this type of result certainly suggests that starting music lessons earlier is more likely to lead to long-lasting neurological benefits.


References

Wang, Y., Xei, L., Zhu, B., Liu, Q., and Dong, Q. (2013). It matters when you start: The age of onset of music training predicts brain anatomy.  Program No. 765.07, Neuroscience 2013 Abstracts, San Diego, CA: Society for Neuroscience, Online.

White-Schwoch, T., Carr, K.W., Anderson, S., Strait, D.L., and Kraus, N. (2013). Older adults benefit from music training early in life: biological evidence for long-term training-driven plasticity. J. Neurosci. 33, 17667–17674.

Tuesday 5 November 2013

Nature and Nurture



There are two excellent reviews out this week, both from top-notch music-and-brain research labs.  And both cover the same general topic:  are musicians made or born?  One paper (by Barrett et al., out of Nina Kraus’ lab at Northwestern University) covers the research showing how musical training alters brain structure and function, while in the other paper, Robert Zatorre of McGill University also discusses the idea of predisposition to learning music.

Scientific studies have shown that there are distinct differences in the brains of musicians compared to non-musicians.  For example, they have larger auditory cortices, larger cerebellums, and greater connections between the two sides of the brain via the corpus callosum.  Current research is trying to figure out whether musician’s brains became that way because of all the musical training, or whether those people became musicians because they were genetically predisposed to having brains like that.  The evidence, thoroughly reviewed by Barrett et al., weighs heavily in support of the idea that musical training does alter the brain.

But that doesn’t mean that there aren’t individual differences in brains and their musical abilities, and specifically in their ability to learn musical skills.  This topic is reviewed by Zatorre, pointing to studies on both speech and music in which subjects can be classified into groups of slow learners or fast learners.  He highlights in particular his own study of micro-interval discrimination in which learning rate was related to the brain’s discriminatory responses before training.  His results indicate that certain pre-existing brain capabilities led to faster learning. It’s not clear (nor does Zatorre make this case) that the differences in learning were based on genetic predisposition rather than environmental factors, but there are obviously individual differences between people, and we know that genetic variability exists. We are all different, after all.

There’s an ongoing and never-ending debate about whether success as a musician (or in any other art or skill) is due to innate aptitude (what some people might call natural talent), or whether it is due to working hard and having access to the right teachers and opportunities.  It’s the old nature-vs-nurture question, and while everyone agrees that both factors play a role, there is much to learn about what role each factor plays. 

It seems that for a long time people have leaned strongly towards the idea that talent is inborn:  either you are a musical person or not.  When I was a teenager, people used to say to me, quite often, how lucky I was to be so musically talented.  And I remember thinking that these people were wrong:  I was just lucky that I enjoyed playing music so much that I was happy to practice a lot.  I fairly recently had a woman ask me if I would listen to her child fool around on the piano, to see if I thought the girl had enough talent that it was worthwhile pursuing music lessons.  My response was that of course she should have piano lessons; her natural musical ability shouldn’t really have any bearing on that decision.  But many people think musical talent is something you are born with.

There is certainly a grain of truth to this idea.  Every music teacher can see that some students find music lessons much easier than others.  These students tend to have certain characteristics that help them:  a good sense of pitch, good fine motor control, an ability to focus their attention, and a willingness to self-correct.  Every person is different, so certainly some people begin music lessons with a head-start.  They may not have had any musical training, but they have already some of the skills that are useful for studying music.  But does that mean they are genetically more musically talented?  Not necessarily.  These things that they’re good at (pitch, motor control) could be there because of other experiences they have had in life.  

On the other hand, I’d bet that every music teacher could also tell you about students who seemed musical but didn’t get far with their lessons because they didn’t practice regularly.  And there are definitely students who start off with seemingly mediocre abilities, but who work hard and learn to play well.  For the last few years I've been teaching a young boy who has always been an inconsistent practicer, just managing to keep up with his class. However, this year he is on a kick of seeing how many days in a row he can practice.  He’s up to almost 300 days of practice, and the difference in his playing is remarkable.  It’s an excellent example that, no matter what your predisposition, if you put in the hours at your instrument, your playing will improve. The experience of playing music changes your musical brain.

Every student is different, and comes to music lessons with their own set of skills, their own capacity for learning, and their own personality. Their brains are all different at the start of their musical training, and they will each develop in different ways. At the same time, every student has the capability to learn well with enough effort.  The job of the music teacher is to be aware of those individual differences so that she can try to strengthen the students’ weak points, and also find ways to motivate the students so that they are willing to put in the daily practice required to improve. I find that the children who seem to have more musical “ability” at the beginning of lessons tend to improve more quickly.  It’s hard to know if this is because they have a genetic advantage, or if they simply are more motivated to practice because they find music easier to start with.  There’s such an interaction between predisposition and experience that it is extremely difficult to untangle them.  Aptitude and hard work are intrinsically linked by motivation.  This is part of what makes nature and nurture inseparable in the debate about where talent comes from.

References

Barrett, K.C., Ashley, R., Strait, D.L., and Kraus, N. (2013). Art and science: how musical training shapes the brain. Front Psychol 4, 713.

Zatorre, R.J. (2013). Predispositions and plasticity in music and speech learning: neural correlates and implications. Science 342, 585–589.