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Brain-based Suggestions for Teaching Reading
Reading in the Brain: The Science and Evolution of a Human Invention
Tuesday, December 15, 2009
In this excerpt from Reading in the Brain, author and French neuroscientist Stanislas Dehaene suggests how teachers might draw from scientific advances to help their students learn to read, though he notes that caution is necessary.
Scientists’ understanding of how our brains enable us to read has advanced significantly in the past two decades. In Reading in the Brain: The Science and Evolution of a Human Invention, French neuroscientist Stanislas Dehaene points out that humans did not have time to evolve reading-specific brain circuitry; instead, our brain “recycles” existing networks for the task. Dehaene not only explains how we learn to read (and what causes reading problems such as dyslexia) but also analyzes scientific insights in the contexts of education and culture.
In this excerpt, Dehaene points out that although caution is necessary when applying the science of reading in the classroom, certain elements of how we learn to read are firm. For example, he challenges the notion “that there are hundreds of ways to learn to read.” As for how teachers might put scientific advances to use, Dehaene says the first step is to make sure children learn how to take words apart and recompose them, associating letters with sounds. Ensuring that students understand not just the mechanics of reading but what the words mean is vital for helping them master this uniquely human ability, he writes.
My comments: Well, the association between letters and sounds does not exist in Chinese.
EXCERPT
From READING IN THE BRAIN by Stanislas Dehaene.
Copyright © 2009 by Stanislas Dehaene.
Reprinted by permission of Viking, a member of Penguin Group (USA) Inc.
From Neuroscience to Education
What we have seen so far is that the acquisition of reading entails massive functional changes in children’s brains. They must first discover phonemes, then map letters onto sounds, and then establish a second lexical reading route. Learning to read implies a literal search for a proper “neuronal niche” for written words in the patchwork of cortical areas for face, object, or color perception.
From a practical standpoint, it is essential to examine whether we can take advantage of these scientific advances to improve teaching. Does our growing understanding of reading lead to clear indications concerning optimal teaching methods? Do some educational techniques ease the transition toward the adult state better than others?
A great deal of caution is needed here. My own impression is that neuroscience is still far from being prescriptive. A wide gap separates the theoretical knowledge accumulated in the laboratory from practice in the classroom. Applications raise problems that are often better addressed by teachers than by the theory-based expectations of scientists. Nevertheless, brain imaging and psychological data cannot be detached from the great pedagogical debates. Relativism notwithstanding, it simply is not true that there are hundreds of ways to learn to read. Every child is unique ... but when it comes to reading, all have roughly the same brain that imposes the same constraints and the same learning sequence. Thus we cannot avoid a careful examination of the conclusions—not prescriptions—that cognitive neuroscience can bring to the field of education.258
To define what reading is not is a good starting point. As overtrained readers, we no longer have much perspective on how difficult reading really is. We tend to believe that one glance at a word will allow its immediate and global identification in a single step. Nothing could be further from the truth. The brain does not go straight from the images of words to their meaning. An entire series of mental and cerebral operations must occur before a word can be decoded. Our brain takes each string apart, then recomposes it into a hierarchy of letters, bigrams, syllables, and morphemes. Effortless reading simply serves to show that these decomposition and recomposition stages have become entirely automatic and unconscious.
With this definition in mind, the goal of reading instruction becomes very clear. It must aim to lay down an efficient neuronal hierarchy, so that a child can recognize letters and graphemes and easily turn them into speech sounds.
All other essential aspects of the literate mind—the mastery of spelling, the richness of vocabulary, the nuances of meaning, and the pleasures of literature—depend on this crucial step. There is no point in describing the delights of reading to children if they are not provided with the means to get there.
Without phonological decoding of written words their chances are significantly reduced. Considerable research, both with children and with illiterates, converges on the fact that grapheme-phoneme conversion radically transforms the child’s brain and the way in which it processes speech sounds. This process whereby written words are converted into strings of phonemes must be taught explicitly. It does not develop spontaneously, and must be acquired.
Reading via the direct route, which leads straight from letter strings to their meaning, only works after many years of practice using the phonological decoding route. ...
My comments: Given this, when it comes to English, good listening and speaking abilities enhance reading.
A Few Suggestions for Educators
In the final analysis, what can psychology and neuroscience recommend to teachers and parents who wish to optimize reading instruction? The growing science of reading has no ready-made formulas, but it does offer a few suggestions.
The punch line is quite simple: we know that conversion of letters into sounds is the key stage in reading acquisition. All teaching efforts should be initially focused on a single goal, the grasp of the alphabetic principle whereby each letter or grapheme represents a phoneme.
In kindergarten, very simple games can prepare children for reading acquisition. At the phonological level, preschoolers benefit from playing with words and their component sounds (syllables, rhymes, and finally phonemes). At the visual level, they can learn to recognize and trace letter shapes. The Montessori method, which requires tracing sandpaper letters with a fingertip, is often of considerable help at this early age. It helps children figure out each letter’s orientation, and makes it clear that “b,” “p,” “d,” and “q” are different letters.
After this preparatory stage, children must be taught, without fear of repetition, how each letter or group of letters corresponds to a phoneme. The child’s brain does not automatically extract these correspondences by dint of seeing a great many words. It must be explicitly told that each speech sound can be represented in different “clothes” (letters or groups of letters) and that each letter can be pronounced in one of several ways. Because English spelling is complex, introduction of graphemes must occur in logical order. Their presentation must start with the simplest and most frequent ones that are almost always pronounced in the same way, such as “t,” “k,” and “a.” Less frequent graphemes (“b,” “m,” “f”), irregular ones (“i,” “o”), or complex ones (“un,” “ch,” “ough”) can be introduced gradually.
My comments: The letter "a" is one of the simplest?
Children’s attention must be drawn to the presence of these individual elements within familiar words. This can be done by assigning each grapheme a distinctive color, or by moving them around to create new words. It should also be explained that letters unfold in a fixed order, from left to right, with no gaps. The ability to attend to the various subcomponents of words is so essential that this must be taught explicitly by, for instance, covering words with a sliding window that reveals only a few letters at a time.
Of course, learning the mechanics of reading is not an end in itself—in the long run, it only makes sense if it leads to meaning. Children must know that reading is not simply mumbling a few syllables—it requires understanding what is written. Each reading period should end with reading words or sentences that can be easily understood and that the child can repeat, summarize, or paraphrase.
A great many teachers will consider my recommendations redundant and obvious—but it does no harm to specify them. I once tried out reading software that was supposedly “award-winning,” where the very first word introduced to the beginning reader was the French word oignon, pronounced onion almost as in English—probably the most irregular spelling in the French language!
Errors as ridiculous as this one clearly show that even the most basic principles of teaching have not yet been absorbed by everyone. Stressing what parents and teachers should not do is equally important. To trace the global contours of words is useless. Likewise, to draw children’s attention to ascending and descending letter patterns is not particularly helpful.
Exercises like these may even be detrimental to reading, inasmuch as they mislead children into paying attention to the global contour of words. This makes them conclude that they can guess at words without examining their component letters one by one. The contours of the words “eight” and “sight” are almost identical. Children need to understand that only the analysis of letters one by one will allow them to discover a word’s identity.
Because of the essential need to avoid distracting the child’s attention from the letter level, I am wary of the many richly decorated reading manuals that contain more illustrations than text. Word posters displayed in classrooms all through the school year, with the same words appearing at the same place, can also create problems. Some children, often the most gifted, merely memorize the fixed position of each word and the general layout of the page and no longer attend to the actual letters in the individual words. This strategy can give teachers and parents—and worst of all, the child himself—the illusion that he knows how to read. Illustrations also divert attention from text. Children now live in a world of constant overstimulation and distraction, so that some no longer learn to sustain attention for long periods of time. A return to sober texts, written on a blackboard during class (so that gesture is also memorized) might be beneficial. It might also be worthwhile to remind the child that although reading is hard work, it has its own inherent reward in the decoding and understanding of text.
Going too fast can also be a handicap. At each step, the words and sentences introduced in class must only include graphemes and phonemes that have already been explicitly taught. Reading lessons provide little room for improvisation. A teacher cannot simply decide, at the last minute, to work on a few unprepared words or sentences. A haphazard choice of this kind will be confusing, because it is very likely to require advanced knowledge that the child has yet to learn.
As expert reading adults, we systematically underestimate how difficult it is to read. The words given to beginning readers must be analyzed letter by letter in order to ensure that they do not contain spelling problems that are beyond the child’s current knowledge—for instance, unusual pronunciations, silent letters, double consonants, or peculiar endings such as the suffix “-tion.” All of these peculiarities, if they are introduced too early in the curriculum, can make children think that reading is arbitrary and not worth studying. As a scientist and a professor myself, I expect the teachers and educators to whom I entrust my children to invest as much obsessive care in the design of lessons as my colleagues and I do when we prepare a psychological experiment.
Finally, guardians of children with reading problems should not give in to despondency. Reading difficulty varies across countries and cultures, and English has probably the most difficult of all alphabetic writing systems. Its spelling system is by far the most opaque—each individual letter can be pronounced in umpteen different ways, and exceptions abound. Comparisons carried out internationally prove that such irregularities have a major impact on learning.270 Italian children, after a few months of schooling, can read practically any word, because Italian spelling is almost perfectly regular. No dictation or spelling exercises for these fortunate children: once they know how to pronounce each grapheme, they can read and write any speech sound. Conversely, French, Danish, and especially British and American children need years of schooling before they converge onto an efficient reading procedure. Even at the age of nine, a French child does not read as well as a seven-year-old German. British children only attain the reading proficiency of their French counterparts after close to two full years of additional teaching.
Barring major spelling reform, there is not much we can do to simplify the acquisition of reading in English. All we can do is encourage our children to practice reading daily ... and to remind ourselves that our situation could be worse. In China, reading lessons extend well into the teens, in order to acquire the several thousand characters needed to read a newspaper. Chinese children’s plight is all the more surprising in that it could be avoided, since most of them nowadays start by learning the simple alphabetical Pinyin notation, which is acquired in a matter of months.271
Teachers can also derive some consolation from bearing in mind that the time spent on learning to read has an extraordinarily profound and useful impact on the child’s brain. Try to picture the ceaseless activity of new connections building up after each reading lesson. Every young reader’s letterbox area is called on to integrate a hierarchy of neurons coding for letters, bigrams, graphemes, and morphemes. This effort creates tremendous neuronal effervescence throughout the reading circuitry. Hundreds of millions of neuronal wires must find their proper targets within other regions coding for speech sounds and meaning. Whether we like it or not, this neuronal hierarchy is far more complex for English or for French than for transparent languages like Italian. The amount of neuronal recycling required for English is so impressive that we must relentlessly teach children to cope with each of its countless spelling pitfalls—even long after the end of elementary school.
My firm conviction is that every teacher should have some notion of how reading operates in the child’s brain. Those of us who have spent many hours debugging computer programs or repairing broken washing machines (as I have done) know that the main difficulty in accomplishing these tasks consists in figuring out what the machine actually does to accomplish a task. To have any hope of success, one must try to picture the state in which it is stuck, in order to understand how it interprets the incoming signals and to identify which interventions will bring it back to the desired state.
Children’s brains can also be considered formidable machines whose function is to learn. Each day spent at school modifies a mind-boggling number of synapses. Neuronal preferences switch, strategies emerge, novel routines are laid down, and new networks begin to communicate with each other. If teachers, like the repairman, can gain an understanding of all these internal transformations, I am convinced that they will be better equipped to discover new and more efficient education strategies. Although pedagogy will never be an exact science, some ways of feeding the brain with written words are more effective than others. Every teacher bears the burden of experimenting carefully and rigorously to identify the appropriate stimulation strategies that will provide students’ brains with an optimal daily enrichment.
References
258. National Institute of Child Health and Human Development. (2000). Report of the National Reading Panel. Teaching children to read: An evidence-based assessment of the scientific research literature on reading and its implications for reading instruction (NIH Publication No. 00–4769). Washington, D.C.: U.S. Government Printing Office.; Rayner, K., Foorman, B. R., Perfetti, C. A., Pesetsky, D., & Seidenberg, M. S. (2001). How psychological science informs the teaching of reading. Psychological Science 2:31–74.…
270. Seymour, P. H., Aro, M., & Erskine, J. M. (2003). Foundation literacy acquisition in European orthographies. British Journal of Psychology 94(Pt 2):143–174.
271. [Discussed in] chapter 2, p. 97.
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