I've been writing these essays for more than 20 years. As with all writers (and other artists), I often look back on my work and shudder. Sometimes, however, I'm okay with what I've written. But how often does someone see a blog post from 2010? Current events may not be relevant anymore and can reasonably be forgotten, and most people don't care about our everyday lives. But I've also said a lot that I think bears repeating; book reviews, for example, are almost always just as useful now as they were then. So I'm going to start to bring back some of my favorites, not only because I believe they'll be useful to what is mostly a whole new audience, but also because I need to be reminded of the content myself.
I'll begin with the fascinating, and important, idea of neuroplasticity, which I first wrote about on May 18, 2010.
The Brain that Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science by Norman Doidge (Penguin, New York, 2007)
The idea that our brains are fixed, hard-wired machines was (and in many cases still is) so deeply entrenched in the scientific establishment that evidence to the contrary was not only suppressed, but often not even seen because the minds of even respectable scientists could not absorb what they were certain was impossible. Having been familiar since the 1960s with the work of Glenn Doman and the Institutes for the Achievement of Human Potential, the idea that the human brain is continually changing itself and can recover from injury in astonishing ways did not surprise me. In fact, the only shock was that in a 400 page book on neuroplasticity and the persecution of its early pioneers I found not one mention of Doman's name. But the stories are none the less astonishing for that.
In Chapter 1 we meet a woman whose vestibular system was destroyed by antibiotic side-effects. She is freed by a sensor held on her tongue and a computerized helmet from the severely disabling feeling that she is falling all the time, even when lying flat. That's the stuff of science fiction, but what's most astounding is that the effect lingers for a few minutes after she removes the apparatus the first time, and after several sessions she no longer needs the device.
Chapter 3, "Redesigning the Brain," on the work of Michael Merzenich, including the ground-breaking Fast ForWord learning program, is worth the cost of the book all by itself.
Sensitive readers may want to steer clear of Chapter 4, "Acquiring Tastes and Loves," or risk being left with unwanted, disturbing mental images. But it is a must read for anyone who wants to believe that pornography is harmless, or that our personal, private mental fantasies do not adversely affect the very structure of our brains.
The book is less impressive when it gets away from hard science and into psychotherapy, as the ideas become more speculative, but the stories are still impressive.
Phantom pain, learning disabilities, autism, stroke recovery, obsessions and compulsions, age-related mental decline, and much more: the discovery of neuroplasticity shatters misconceptions and offers hope. The Brain that Changes Itself is an appetizer plate; bring on the main course!
For those who want a sampling of the appetizer itself, I'm including an extensive quotation section. Even so, it doesn't come close to doing justice to the depth and especially the breadth of the book. I've pulled quotes from all over, so understand that they are out of context, and don't expect them to move smoothly from one section to another.
Neuro is for "neuron," the nerve cells in our brains and nervous systems. Plastic is for "changeable, malleable, modifiable." At first many of the scientists didn't dare use the word "neuroplasticity" in their publications, and their peers belittled them for promoting a fanciful notions. Yet they persisted, slowly overturning the doctrine of the unchanging brain. They showed that children are not always stuck with the mental abilities they are born with; that the damaged brain can often reorganize itself so that when one part fails, another can often substitute; that if brain cells die, they can at times be replaced; that many "circuits" and even basic reflexes that we think are hardwired are not. One of these scientists even showed that thinking, learning, and acting can turn our genes on or off, thus shaping our brain anatomy and our behavior—surely one of the most extraordinary discoveries of the twentieth century.
In the course of my travels I met a scientist who enabled people who had been blind since birth to begin to see, another who enabled the deaf to hear; I spoke with people who had had strokes decades before and had been declared incurable, who were helped to recover with neuroplastic treatments; I met people whose learning disorders were cured and whose IQs were raised; I saw evidence that it is possible for eighty-year-olds to sharpen their memories to function the way they did when they were fifty-five. I saw people rewire their brains with their thoughts, to cure previously incurable obsessions and traumas. I spoke with Nobel laureates who were hotly debating how we must re-think our model of the brain now that we know it is ever changing. ... The idea that the brain can change its own structure and function through thought and activity is, I believe, the most important alteration in our view of the brain since we first sketched out its basic anatomy and the workings of its basic component, the neuron.
In Chapter 2, Building Herself a Better Brain, a woman with such a severe imbalance of brain function that she was labelled mentally retarded put her own experiences together with the work of other researchers to design brain exercises that fixed the weaknesses in her own brain ... and went on to develop similar diagnostic procedures and exercises for others.
The irony of this new discovery is that for hundreds of years educators did seem to sense that children's brains had to be built up through exercises of increasing difficulty that strengthened brain functions. Up through the nineteenth and early twentieth centuries a classical education often included rote memorization of long poems in foreign languages, which strengthened the auditory memory (hence thinking in language) and an almost fanatical attention to handwriting, which probably helped strengthen motor capacities and thus not only helped handwriting but added speed and fluency to reading and speaking. Often a great deal of attention was paid to exact elocution and to perfecting the pronunciation of words. Then in the 1960s educators dropped such traditional exercises from the curriculum, because they were too rigid, boring, and "not relevant." But the loss of these drills has been costly; they may have been the only opportunity that many students had to systematically exercise the brain function that gives us fluency and grace with symbols. For the rest of us, their disappearance may have contributed to the general decline of eloquence, which requires memory and a level of auditory brainpower unfamiliar to us now. In the Lincoln-Douglas debates of 1858 the debaters would comfortably speak for an hour or more without notes, in extended memorized paragraphs; today many of the most learned among us, raised in our most elite schools since the 1960s, prefer the omnipresent PowerPoint presentation—the ultimate compensation for a weak premotor cortex.
Here are several (but not enough!) from my favorite chapter, "Redesigning the Brain."
[As] they trained an animal at a skill, not only did its neurons fire faster, but because they were faster their signals were clearer. Faster neurons were more likely to fire in sync with each other—becoming better team players—wiring together more and forming groups of neurons that gave off clearer and more powerful signals. This is a crucial point, because a powerful signal has greater impact on the brain. When we want to remember something we have heard we must hear it clearly, because a memory can be only as clear as its original signal.
Paying close attention is essential to long-term plastic change. ... When the animals performed tasks automatically, without paying attention, they changed their brain maps, but the changes did not last. We often praise "the ability to multitask." While you can learn when you divide your attention, divided attention doesn't lead to abiding change in your brain maps.
Somewhere between 5 and 10 percent of preschool children have a language disability that makes it difficult for them to read, write, or even follow instructions. ... [C]hildren with language disabilities have auditory processing problems with common consonant-vowel combinations that are spoken quickly and are called "the fast parts of speech." The children have trouble hearing them accurately and, as a result, reproducing them accurately. Merzenich believed that these children's auditory cortex neurons were firing too slowly, so they couldn't distinguish between two very similar sounds or be certain, if two sounds occurred close together, which was first and which was second. Often they didn't hear the beginnings of syllables or the sound changes within syllables. Normally neurons, after they have processed a sound, are ready to fire again after about a 30-millisecond rest. Eighty percent of language-impaired children took at least three times that long, so that they lost large amounts of language information. When their neuron-firing patterns were examined, the signals weren't clear. ... Improper hearing lead to weaknesses in all the language tasks, so they were weak in vocabulary, comprehension, speech, reading, and writing. Because they spent so much energy decoding words, they tended to use shorter sentences and failed to exercise their memory for longer sentences.
[Five hundred children at 35 sites] were given standardized language tests before and after Fast ForWord training. The study showed that most children's ability to understand language normalized after Fast ForWord. In many cases, their comprehension rose above normal. The average child who took the program moved ahead 1.8 years of language development in six weeks. ... A Stanford group did brain scans of twenty dyslexic children, before and after Fast ForWord. The opening scans showed that the children used different parts of their brains for reading than normal children do. After Fast ForWord new scans showed that their brains had begun to normalize.
Merzenich's team started hearing that Fast ForWord was having a number of spillover effects. Children's handwriting improved. Parents reported that many of the students were starting to show sustained attention and focus. Merzenich thought these surprising benefits were occurring because Fast ForWord led to some general improvements in mental processing.
"You know," [Merzenich] says, "IQ goes up. We used the matrix test, which is a visual-based measurement of IQ—and IQ goes up."
The fact that a visual component of the IQ went up meant that the IQ improvements were not caused simply because Fast ForWord improved the children's ability to read verbal test questions. Their mental processing was being improved in a general way.
This is just a sample of the benefits that made me want to rush right out and buy Fast ForWord, even if it were to cost as much as the insanely-expensive Rosetta Stone German software I'm also tempted to buy. From the description, it sounds like something everyone could benefit from for mental tune-ups. Unfortunately, the makers of Fast ForWord are even worse than the Rosetta Stone folks about keeping tight control over their product: as far as I've been able to determine, you can only use it under the direction of a therapist (making it too expensive for ordinary use), and even then you don't own the software but are only licensed to use it for a short period of time. :( It works, though. We know someone for whom it made all the difference in the world, even late in her school career.
Merzenich began wondering about the role of a new environmental risk factor that might affect everyone but have a more damaging effect on genetically predisposed children: the continuous background noise from machines, sometimes called white noise. White noise consists of many frequencies and is very stimulating to the auditory cortex.
"Infants are reared in continuously more noisy environments. There is always a din," he says. White noise is everywhere now, coming from fans in our electronics, air conditioners, heaters, and car engines.
To test this hypothesis, his group exposed rat pups to pulses of white noise throughout their critical period and found that the pups' cortices were devastated.
Psychologically, middle age is often an appealing time because, all else being equal, it can be a relatively placid period compared with what has come before. ... We still regard ourselves as active, but we have a tendency to deceive ourselves into thinking that we are learning as we were before. We rarely engage in tasks in which we must focus our attention as closely as we did when we were younger. Such activities as reading the newspaper, practicing a profession of many years, and speaking our own language are mostly the replay of mastered skills, not learning. By the time we hit our seventies, we may not have systematically engaged the systems in the brain that regulate plasticity for fifty years.
That's why learning a new language in old age is so good for improving and maintaining the memory generally. Because it requires intense focus, studying a new language turns on the control system for plasticity and keeps it in good shape for laying down sharp memories of all kinds. No doubt Fast ForWord is responsible for so many general improvements in thinking, in part because it stimulates the control system for plasticity to keep up its production of acetylcholine and dopamine. Anything that requires highly focused attention will help that system—learning new physical activities that require concentration, solving challenging puzzles, or making a career change that requires that you master new skills and material. Merzenich himself is an advocate of learning a new language in old age. "You will gradually sharpen everything up again and that will be very highly beneficial to you."
The same applies to mobility. Just doing the dances you learned years ago won't help your brain's motor cortex stay in shape. To keep the mind alive requires learning something truly new with intense focus. That is what will allow you to both lay down new memories and have a system that can easily access and preserve the older ones.
This work opens up the possibility of high-speed learning later in life. The nucleus basalis [always on for young children, but in adulthood only with sustained, close attention] could be turned on by an electrode, by microinjections of certain chemicals, or by drugs. It is hard to imagine that people will not ... be drawn to a technology that would make it relatively effortless to master the facts of science, history, or a profession, merely by being exposed to them briefly. ... Such techniques would no doubt be used by high school and university students in their studies and in competitive entrance exams. (Already many students who do not have attention deficit disorder use stimulants to study.) Of course, such aggressive interventions might have unanticipated, adverse effects on the brain—not to mention our ability to discipline ourselves—but they would likely be pioneered in cases of dire medical need, where people are willing to take the risk. Turning on the nucleus basalis might help brain-injured patients, so many of whom cannot relearn the lost functions of reading, writing, speaking, or walking because they can't pay close enough attention.
[Gross motor control is] a function that declines as we age, leading to loss of balance, the tendency to fall, and difficulties with mobility. Aside from the failure of vestibular processing, this decline is caused by the decrease in sensory feedback from our feet. According to Merzenich, shoes, worn for decades, limit the sensory feedback from our feet to our brain. If we went barefoot, our brains would receive many different kinds of input as we went over uneven surfaces. Shoes are a relatively flat platform that spreads out the stimuli, and the surfaces we walk on are increasingly artificial and perfectly flat. This leads us to dedifferentiate the maps for the soles of our feet and limit how touch guides our foot control. Then we may start to use canes, walkers, or crutches or rely on other senses to steady ourselves. By resorting to these compensations instead of exercising our failing brain systems, we hasten their decline.
As we age, we want to look down at our feet while walking down stairs or on slightly challenging terrain, because we're not getting much information from our feet. As Merzenich escorted his mother-in-law down the stairs of the villa, he urged her to stop looking down and start feeling her way, so that she would maintain, and develop, the sensory map for her foot, rather than letting it waste away.
Brain plasticity and psychological disorders:
Each time [people with obsessive-compulsive disorder] try to shift gears, they begin ... growing new circuits and altering the caudate. By refocusing the patient is learning not to get sucked in by the content of an obsession but to work around it. I suggest to my patients that they think of the use-it-or-lose-it principle. Each moment they spend thinking of the symptom ... they deepen the obsessive circuit. By bypassing it, they are on the road to losing it. With obsessions and compulsions, the more you do it, the more you want to do it; the less you do it, the less you want to do it ... [I]t is not what you feel while applying the technique that counts, it is what you do. "The struggle is not to make the feeling go away; the struggle is not to give in to the feeling"—by acting out a compulsion, or thinking about the obsession. This technique won't give immediate relief because lasting neuroplastic change takes time, but it does lay the groundwork for change by exercising the brain in a new way. ... The goal is to "change the channel" to some new activity for fifteen to thirty minutes when one has an OCD symptom. (If one can't resist that long, any time spent resisting is beneficial, even if it is only for a minute. That resistance, that effort, is what appears to lay down new circuits.)
Mental practice with physical results:
Pascual-Leone taught two groups of people, who had never studied piano, a sequence of notes, showing them which fingers to move and letting them hear the notes as they were played. Then members of one group, the "mental practice" group, sat in front of an electric piano keyboard, two hours a day, for five days, and imagined both playing the sequence and hearing it played. A second "physical practice" group actually played the music two hours a day for five days. Both groups had their brains mapped before the experiment, each day during it, and afterward. Then both groups were asked to play the sequence, and a computer measured the accuracy of their performances.
Pascual-Leoone found that both groups learned to play the sequence, and both showed similar brain map changes. Remarkably, mental practice alone produced the same physical changes in the motor system as actually playing the piece. By the end of the fifth day, the changes in motor signals to the muscles were the same in both groups, and the imagining players were as accurate as the actual players were on their third day.
The level of improvement at five days in the mental practice group, however substantial, was not as great as in those who did physical practice. But when the mental practice group finished its mental training and was given a single two-hour physical practice session, its overall performance improved to the level of the physical practice group's performance at five days. Clearly mental practice is an effective way to prepare for learning a physical skill with minimal physical practice.
In an experiment that is as hard to believe as it is simple, Drs. Guang Yue and Kelly Cole showed that imagining one is using one's muscles actually strengthens them. The study looked at two groups, one that did physical exercise and one that imagined doing exercise. ... At the end of the study the subjects who had done physical exercise increased their muscular strength by 30 percent, as one might expect. Those who only imagined doing the exercise, for the same period, increased their muscle strength by 22 percent. The explanation lies in the motor neurons of the brain that "program" movements. During these imaginary contractions, the neurons responsible for stringing together sequences of instructions for movements are activated and strengthened, resulting in increased strength when the muscles are contracted.
Talk about unbelievable.
The Sea Gypsies are nomadic people who live in a cluster of tropical islands in the Burmese archipelago and off the west coast of Thailand. A wandering water tribe, they learn to swim before they learn to walk and live over half their lives in boats on the open sea. ... Their children dive down, often thirty feet beneath the water's surface, and pluck up their food ... and have done so for centuries. By learning to lower their heart rate, they can stay under water twice as long as most swimmers. They do this without any diving equipment.
But what distinguishes these children, for our purposes, is that they can see clearly at these great depths, without goggles. Most human beings cannot see clearly under water because as sunlight passes through water, it is bent ... so that light doesn't land where it should on the retina.
Anna Gislén, a Swedish researcher, studied the Sea Gypsies' ability to read placards under water and found that they were more than twice as skillful as European children. The Gypsies learned to control the shape of their lenses and, more significantly, to control the size of their pupils, constricting them 22 percent. This is a remarkable finding, because human pupils reflexively get larger under water, and pupil adjustment has been thought to be a fixed, innate reflex, controlled by the brain and nervous system.
This ability of the Sea Gypsies to see under water isn't the product of a unique genetic endowment. Gislén has since taught Swedish children to constrict their pupils to see under water.
The fact that cultures differ in perception is not proof that one perceptual act is a good as the next, or that "everything is relative" when it comes to perception. Clearly some contexts call for a more narrow angle of view, and some for more wide-angle, holistic perception. The Sea Gypsies have survived using a combination of their experience of the sea and holistic perception. So attuned are they to the moods of the sea that when the tsunami of December 26, 2004, hit the Indian Ocean, killing hundreds of thousands, they all survived. They saw that the sea had begun to recede in a strange way, and this drawing back was followed by an unusually small wave; they saw dolphins begin to swim for deeper water, while the elephants started stampeding to higher ground, and they heard the cicadas fall silent. ... Long before modern science put this all together, they had either fled the sea to the shore, seeking the highest ground, or gone into very deep waters, where they also survived.
Music makes extraordinary demands on the brain. A pianist performing the eleventh variation of the Sixth Paganini etude by Franz Liszt must play a staggering eighteen hundred notes per minute. Studies by Taub and others of musicians who play stringed instruments have shown that the more these musicians practice, the larger the brain maps for their active left hands become, and the neurons and maps that respond to string timbres increase; in trumpeters the neurons and maps that respond to "brassy" sounds enlarge. Brain imaging shows that musicians have several areas of their brains—the motor cortex and the cerebellum, among others—that differ from those of nonmusicians. Imaging also shows that musicians who begin playing before the age of seven have larger brain areas connecting the two hemispheres.
It is not just "highly cultured" activities that rewire the brain. Brain scans of London taxi drivers show that the more years a cabbie spends navigating London streets, the larger the volume of his hippocampus, that part of the brain that stores spatial representations. Even leisure activities change our brain; meditators and meditation teachers have a thicker insula, a part of the cortex activated by paying close attention.
Here's something completely different, and frightening.
[T]otalitarian regimes seem to have an intuitive awareness that it becomes hard for people to change after a certain age, which is why so much effort is made to indoctrinate the young from an early age. For instance, North Korea, the most thoroughgoing totalitarian regime in existence, places children in school from ages two and a half to four years; they spend almost every waking hour being immersed in a cult of adoration for dictator Kim Jong Il and his father, Kim Il Sung. They can see their parents only on weekends. Practically every story read to them is about the leader. Forty percent of the primary school textbooks are devoted wholly to describing the two Kims. This continues all the way through school. Hatred of the enemy is drilled in with massed practice as well, so that a brain circuit forms linking the perception of "the enemy" with negative emotions automatically. A typical math quiz asks, "Three soldiers from the Korean People's Army killed thirty American soldiers. How many American soldiers were killed by each of them, if they all killed an equal number of enemy soldiers?" Such perceptual emotional networks, once established in an indoctrinated people, do not lead only to mere "differences of opinion" between them and their adversaries, but to plasticity-based anatomical differences, which are much harder to bridge or overcome than ordinary persuasion.
Think the North Koreans are the only ones whose brains are being re-programed?
"The Internet is just one of those things that contemporary humans can spend millions of 'practice' events at, that the average human a thousand years ago had absolutely no exposure to. Our brains are massively remodeled by this exposure—but so, too, by reading, by television, by video games, by modern electronics, by contemporary music, by contemporary 'tools,' etc." — Michael Merzenich, 2005
Erica Michael and Marcel Just of Carnegie Mellon University did a brain scan study to test whether the medium is indeed the message. They showed that different brain areas are involved in hearing speech and reading it, and different comprehension centers in hearing words and reading them. As Just put it, "The brain constructs the message ... differently for reading and listening. ... Listening to an audio book leaves a different set of memories than reading does. A newscast heard on the radio is processed differently from the same words read in a newspaper." This finding refutes the conventional theory of comprehension, which argues that a single center in the brain understands words, and it doesn't really matter how ... information enters the brain.
Television, music videos, and video games, all of which use television techniques, unfold at a much faster pace than real life, and they are getting faster, which causes people to develop an increased appetite for high-speed transitions in those media. It is the form of the television medium—cuts, edits, zooms, pans, and sudden noises—that alters the brain, by activating what Pavlov called the "orienting response," which occurs whenever we sense a sudden change in the world around us, especially a sudden movement. We instinctively interrupt whatever we are doing to turn, pay attention, and get our bearings. ... Television triggers this response at a far more rapid rate than we experience it in life, which is why we can't keep our eyes off the TV screen, even in the middle of an intimate conversation, and why people watch TV a lot longer than they intend. Because typical music videos, action sequences, and commercials trigger orientating responses at a rate of one per second, watching them puts us into continuous orienting response with no recovery. No wonder people report feeling drained from watching TV. Yet we acquire a taste for it and find slower changes boring. The cost is that such activities as reading, complex conversation, and listening to lectures become more difficult.
All electronic devices rewire the brain. People who write on a computer are often at a loss when they have to write by hand or dictate, because their brains are not wired to translate thoughts into cursive writing or speech at high speed. When computers crash and people have mini-nervous breakdowns, there is more than a little truth in their cry, "I feel like I've lost my mind!" As we use an electronic medium, our nervous system extends outward, and the medium extends inward.
"Use it or lose it" is a common refrain in The Brain that Changes Itself, whether talking about specific knowledge and abilities, or the capacity for learning and the very plasticity of the brain itself. (There is some hope given, however, that knowledge apparently lost is recoverable, even if its brain "map" has subsequently been taken over for another use.) Do you worry, as I did, that these new discoveries mean that it really is possible to learn too much, that we need to save our brains for that which is most important? That learning German will drive away what little I know of French? Relax; that doesn't need to happen, although I must be sure to keep the French fresh in my mind or it will get shelved.
As the scientist Gerald Edelman has pointed out, the human cortex alone has 30 billion neurons and is capable of making 1 million billion synaptic connections. Edelman writes, "If we considered the number of possible neural circuits, we would be dealing with hyper-astronomical numbers: 10 followed by at least a million zeros. (There are 10 followed by 79 zeros, give or take a few, of particles in the known universe.)" These staggering numbers explain why the human brain can be described as the most complex known object in the universe, and why it is capable of ongoing, massive microstructural change, and capable of performing so many different mental functions and behaviors.
I'm tired of typing. Get the book.