Monday, March 12, 2007

Myelination and Horizontality

There was an interesting article in the March 4 Sunday N.Y. Times magazine by Daniel Coyle entitle "How to Grow a Super Athlete." The article focuses on training methods which result in superior performance, which is interesting from a pedagogical point of view, but it also includes one of the best summaries I've seen in print of recent brain research involving neuroplasticity, and especially the role of repetitive instruction in stimulating the development of myelin around brain cells. I had heard about recent research involving the the role of instruction in stimulating physical changes in the brain, but this article brought them into sharp focus. At one point in the article, Coyle is talking with Douglas Fields, the director of the National Institute of Health in Bethesda, Maryland:
Fields proceeded to explain that myelin is a sausage-shaped layer of dense fat that wraps around the nerve fibers — and that its seeming dullness is, in fact, exactly the point. Myelin works the same way that rubber insulation works on a wire, keeping the signal strong by preventing electrical impulses from leaking out. This myelin sheath is, basically, electrical tape, which is one reason that myelin, along with its associated cells, was classified as glia (Greek for "glue"). Its very inertness is why the first brain researchers named their new science after the neuron instead of its insulation. They were correct to do so: neurons can indeed explain almost every class of mental phenomenon—memory, emotion, muscle control, sensory perception and so on. But there's one question neurons can't explain: why does it take so long to learn complex skills?

"Everything neurons do, they do pretty quickly; it happens with the flick of a switch," Fields said. "But flicking switches is not how we learn a lot of things. Getting good at piano or chess or baseball takes a lot of time, and that's what myelin is good at."

To the surprise of many neurologists, it turns out this electrical tape is quietly interacting with the neurons. Through a mechanism that Fields and his research team described in a 2006 paper in the journal Neuron, the little sausages of myelin get thicker when the nerve is repeatedly stimulated. The thicker the myelin gets, the better it insulates and the faster and more accurately the signals travel. As Fields puts it, "The signals have to travel at the right speed, arrive at the right time, and myelination is the brain's way of controlling that speed."

It adds up to a two-part dynamic that is elegant enough to please Darwin himself: myelin controls the impulse speed, and impulse speed is crucial. The better we can control it, the better we can control the timing of our thoughts and movements, whether we're running, reading, singing or, perhaps more to the point, hitting a wicked topspin backhand.
Coyle also spends some time at the Spartak Tennis Club in Moscow. Coyle contextulizes Spartak's success this way: "this club, which has one indoor court, has achieved eight year-end top-20 women's rankings over the last three years. During that same period, the entire United States has achieved seven." So what's going on at Spartak? Well, they're being very systematic about repeatedly stimulating certain nerves in the brain, a process some researchers call "myelinating." Coyle describes what he learned from Larisa Preobrazhenskaya, the woman who heads up Spartak:

If Preobrazhenskaya's approach were boiled down to one word (and it frequently was), that word would be tekhnika — technique. This is enforced by iron decree: none of her students are permitted to play in a tournament for the first three years of study. It's a notion that I don't imagine would fly with American parents, but none of the Russian parents questioned it for a second. "Technique is everything," Preobrazhenskaya told me later, smacking a table with Khrushchev-like emphasis, causing me to jump and reconsider my twinkly-grandma impression of her. "If you begin playing without technique, it is big mistake. Big, big mistake!"

I thought of something Dr. Fields had said: "You have to understand that every skill exists as a circuit, and that circuit has to be formed and optimized." To put it in Spartak terms, myelin is a slave to tekhnika — and so, in turn, was the Little Group. Preobrazhenskaya didn't instruct them on tactics or positioning or offer any psychological tips; rather, every gesture and word was funneled to teaching the elemental task of hitting the ball clean and hard. Which they did, one by one. A few of the kids had located that magical-seeming burst of leverage that makes the ball explode off the strings with a distinctive thwock.

"What do good athletes do when they train?" George Bartzokis, a professor of neurology at U.C.L.A., had told me. "They send precise impulses along wires that give the signal to myelinate that wire. They end up, after all the training, with a super-duper wire — lots of bandwidth, high-speed T-1 line. That's what makes them different from the rest of us."
The article has got me thinking about the implications of all this. I would have to confess that tekhnika is not my definition of educational nirvana. I am not by disposition or experience inclined to endorse a drills-and-skills approach to instruction, and yet I have experienced at first hand as a (not very capable) musician—and, in earlier days, as an athlete—how frequent, deliberate repetition of isolated elements of difficult passages eventually leads to a facility that at first seems unattainable. Eventually, with practice, you get better.

So I guess one question would be, "What do good students do when they train?" Should our role as teacher-coaches be to put our students into situations where they are going to repetitively send precise impulses to certain areas of the brain? That begins to sound like an argument for precisely the kind of homework "exercises" that have come under fire from people like Alfie Kohn. Are there some kinds of repetition that are better than others, some that are in fact essential? Are there some sequences of questions, like the ones I referred to in Friday's post, that when asked often enough begin stimulate myeliniation, thereby over time resulting in greater critical thinking ability? How does what we are beginning to learn about brain chemistry help us to make better decisions about instructional practice?

I don't have answers to any of those questions. Yesterday I was at a picnic talking with a colleague about the condition of more or less chronic overstimulation that I have found myself in during the last few years as an educator. I guess I always have felt this way to some degree, but somehow I thought that with increasing age and experience, and presumably, wisdom, that it would get easier. As if. Everywhere I look, there's more think about, and any one of the territories might take a lifetime to explore with any thoroughness. And the fact that there are now internet resources at my fingertips that allow me to go sailing off into the territories of horizontality for long period of time is both a blessing and a kind of curse. Without even stopping to think about, I can say that on campus right now there are ongoing conversations and explorations about sustainability, Web 2.0, constructivist learning, brain research, alternative assessment, service learning, global education, and character education. Sometimes it feels like all of those conversations are essential, and I'm really happy to be engaged in them. Sometimes it just feels like my brain is going to explode. And sometimes, like now, I look at the clock and see it's moving in on 10:00 and if I'm going to be able to get up in the morning what I really need to do is stop writing and go to sleep. So that, gentle reader, is what I am about to do. Tomorrow, as my mother was fond of saying, in her best O'haran accent, is another day.

No comments: