A book in praise of reading verges on tautology. Nobody likely to read Proust and the Squid will need to be told that reading generates thought, or that it gives a feeling of inner selfhood. Maryanne Wolf puts Proust into her book because she likes his account of reading’s pleasures. But any reader will know them already without Proust’s help. The squid part of her book is more interesting. Scientists in the 1950s used the squid’s nervous system to discover how neurons transmit to each other, and this leads Wolf to an account of how today’s cognitive neuroscientists are finding out what happens inside a human brain when it learns to read.

Put simply (not always Wolf’s strong suit), before a brain can read it must physically rearrange itself. It must create new neuronal circuits to connect the part it uses for seeing with the part it uses for listening to someone talk. Not until it does this will the brain’s owner realise that marks on paper represent sounds. Some brains never manage it, or do so only imperfectly. Their owners used to be dismissed as stupid. But we now know some of them are highly gifted. Among famous dyslexics Wolf lists Leonardo da Vinci, Einstein, Picasso, Edison and Alexander Graham Bell. Why did these exceptional beings fail to master a skill ordinary mortals easily acquire?

To set the scene for answering that question Wolf takes us through a brief history of written languages, starting with Sumerian cuneiform in about 3000BC. Broadly speaking, the development over time was from languages that represented things by pictures, as in Egyptian hieroglyphics, to languages where written symbols stood for syllables in the spoken language. Then came the great breakthrough when the Greeks invented the alphabet, in which a limited number of letters can convey all the language’s basic sounds. That is presumably when dyslexia started, because dyslexics could not match up the letters and the sounds. On the plus side, many linguists believe that the invention of the alphabet greatly increased the human brain’s capacity for new thought and abstract ideas. It was this single invention, they argue, that made possible the flowering of Greek drama, science, art and philosophy which gave birth to western culture.

But if an alphabet is so important, is it the case that humans who do not have an alphabet think differently from those who do? Does an alphabet build a different brain? It is not a trivial question, because one of the world’s main languages, Chinese, does not have an alphabet. Further, neuroscience can now demonstrate that not having an alphabet does indeed cause the brain to organise itself differently. Brain scans show that when someone reads an alphabetical language, such as English, specialised parts of the brain’s left hemisphere are activated. But when a Chinese speaker reads Chinese, quite different parts of the brain are used. They are in both hemispheres, and include frontal areas not used for reading by English readers. Since this proves that the Chinese reader’s brain is connected up differently, it prompts the question whether Chinese thought is different from western thought. Linguists used to argue that there is always a relationship between the language a person speaks and how that person understands the world. This idea fell out of favour under the influence of Chomskyan linguistics and theories of universal grammar. But the advent of the brain scan seems to be reopening the question. What Wolf’s own views are it is impossible to say. Having presented the brain-scan evidence, she refrains from speculating about how the Chinese think. No doubt her failure to grasp this hot potato is a mark of prudence. All the same, it is a bit of a let-down for readers who have followed her excitedly through a couple of hundred pages.

The topic she really cares about, and moves on to in her last section, is dyslexia. A cognitive neuroscientist herself, she heads a dyslexia research team at Tufts University, and has a dyslexic son. She is careful to stress that there are various kinds of dyslexia, not all of them covered by the research she summarises. But what that research reveals, fascinatingly, is that some dyslexic brains are, like the Chinese brain, differently constructed from the normal western reader’s. Instead of using left-hemisphere circuits for reading, these dyslexic brains create new and less efficient circuits for reading in the brain’s right hemisphere. Why, is not clear. It may be because the right hemispheres of these brains were more dominant from the start, or possibly because weaknesses in the left hemisphere forced the brain to develop analogous areas in the right for reading. Either way, it might explain why many artists and inventors were dyslexic, since the right hemisphere, Wolf points out, is better suited to large-scale operations such as creativity and pattern recognition, rather than the precision and timing needed for speech and writing.

Perhaps this discovery will lead to more successful treatment for some dyslexics. Meanwhile, Wolf offers practical advice to parents on how to encourage children’s reading. Being talked to, read to and listened to all matter. It is estimated that, by the age of five, a child in a home where lots of talking goes on will have heard 32m more words spoken than a child in a linguistically impoverished household. How often a child has stories read to it in its first five years is a dependable predictor of its later reading skills, and how the reading is done makes a difference. Sitting on a parent’s knee to be read to means that the child will link reading with being loved. Nursery rhymes, with their alliterations and assonances, train children’s ears and brains in the phoneme recognition that they need for reading.

Unfortunately, Wolf’s advice will not reach those who need it most. What her findings amount to is that many children are already failures before they go to school, because they come from semi-literate, semi-articulate homes. How to alter that (short of Plato’s solution, which was to take all children from their parents at birth and bring them up properly), nobody knows.

Perhaps the internet offers hope. Wolf is suspicious of it. The “Google universe” that children inhabit worries her, and she fears that “deep examination of words, thought, reality and virtue” will die out if young people turn from books to computer-presented texts. It is hard to see why. She offers no evidence that reading a book and reading from a screen activate the brain differently. True, computers do not have laps to sit on, but they put an unprecedented range of knowledge, and the texts of many literary classics, within reach of the young.

If our children do not value reading and thinking, it is probably because we have taught them to value money and fame more, rather than any inherent fault in computers. That said, Wolf’s alarm about the spread of semi-literacy among the young is obviously justified, and her book provokes thought about it as only reading can.

Dyslexia could spell genius

The best present for a dyslexic is surely a facsimile of Leonardo da Vinci’s notebooks. His notes, written from right to left, in reversed “looking-glass script”, are full of misspellings, syntactic mistakes and strange errors. Several of his biographers mention his discomfort with language and his frequent references to his lack of reading ability. Einstein, too, exhibited several symptoms of dyslexia. He barely spoke until he was three, was mediocre at foreign languages and had a bad memory for words, which he said did “not seem to play any role” in his theoretical thinking. This came to him instead through “more or less clear images”.

Proust and the Squid: The Story of Science and the Reading Brain by Maryanne Wolf
Icon £12.99 pp322

John Carey discusses John Milton and his English language at the Sunday Times Oxford Literary Festival, on Friday, April 4, at 6.30pm; to book, contact www.ticketsoxford.com.

Proust and the Squid is available at the Books First price of £11.69 (inc p&p) on 0870 165 8585

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