Writing in English can be a challenge – even if it's your mother tongue.

Alex loved books and languages. His parents were native English speakers, and the family lived in Japan, so Alex spoke English at home, and Japanese at school. At the age of 13, however, Alex was diagnosed with dyslexia, a learning difficulty that affects reading and writing. According to test results, his English reading level was that of a six-year-old.

The results were a shock. "This test came along and they were like, actually, your writing is horrible," Alex recalls. "I thought I was doing ok. Yes, there was a bit of a struggle, but I assumed everyone else was struggling. In fact, the numbers that came out were quite devastating from my perspective."

To researchers, the even bigger surprise was his performance in the other language he used. When he was tested in Japanese at the age of 16, his literacy was not just good. It was excellent.

"We compared his Japanese test results to those of 20-year-old Japanese university students," says Taeko Wydell, a professor in cognitive neuroscience at Brunel University London, and one of the researchers who studied Alex's case in the late 1990s and early 2000s. "He was often equivalent, and sometimes better, than those university students. So he was a really able reader in Japanese." His writing was also very good.

Alex wasn't particularly surprised by the Japanese test results himself: after all, he liked reading, and he read a lot. What puzzled him more was the struggle with English. As the test showed, "I spoke very well, and my vocabulary was large, but I could not spell to save my life. It was quite a blow to my self-confidence, but also fascinating."

How was this dramatic contrast possible, given that dyslexia is commonly thought of as an innate, lifelong condition?

The answer lies in how our brain processes writing – and how different languages are written.

For those who read effortlessly, it may be surprising to hear just how hard our brain has to work to make sense of the marks on a page. Reading requires good verbal memory, for example. In English, readers also have to know which sounds the different letters represent, and how those sounds make up words – a skill known as phonological awareness.

Children with dyslexia typically struggle with that. They may not be able to say which sounds make up the word "hot", how they differ from "hat", and which word you get if you switch the "h" for a "p". To this day, Alex (who prefers not to give his full name for privacy reasons) says he finds it hard to tell the difference between similar words such as "spear" and "spare". He also finds reading aloud particularly tricky, as it involves an extra layer of phonological processing.

That phonological difficulty is less of an issue in scripts with more picture-based characters, such as Japanese writing.

But that's not all there is to it. For a start, Japanese also has words that are spelled out. And yet, spelling those words is still easier than it is in English – and not just for Alex. That's because Alex's story is a dramatic example of a much broader phenomenon, affecting people of all abilities: how well you read and write can depend on the language you are using.

Consider, for example, how long it takes children to learn to read in different languages, or more specifically, in different orthographies (spelling systems).

"There is quite a lot of evidence that learning to read in English just takes longer because it's harder than other orthographies," says Karin Landerl, a professor of developmental psychology at the University of Graz, Austria.

Children who speak languages as diverse as Welsh, Spanish, Czech, Finnish and many others, all tend to learn to read more quickly than English-speakers.

Welsh children can read more words in Welsh than English children of the same age can in English. In Finland, most children can read within a few months of starting school, while it takes English-speaking children much longer. A study comparing children learning to read in English, Spanish and Czech found that reading skills in the latter two languages soared soon after the start of instruction, while the English-speaking children progressed more slowly.

One reason is that English is spelled somewhat chaotically. While the English pronounciation of many words has changed over time, the spelling has remained the same, Landerl says. "And English has always been very tolerant towards other languages and tends to absorb foreign words along with their original spelling."

As a result, the way a word looks on the page may not be how it is pronounced. The same sound can be written in different ways (such as the "ite" sound in light and kite), and the same letters may be read with a totally different sound (such as the "ea" in steak, meat, learn, bread). Wydell points out that "ink" is always consistent – think, sink, pink, and so on. But "int" seems consistent… until it is not: mint, lint, tint, but then: pint. There are words like yacht, that just have to be memorised – but also, words like cat, which can be read letter by letter.

"If you try to learn to read in English, and you don't have a good phonological awareness – an awareness for the sounds of spoken language – it can lead to massive difficulties," says Landerl. "Because you don't understand how the letters and sounds fit together."

In languages such as Finnish, Hungarian, Basque, Welsh, Albanian, Spanish, Czech, Italian and German, the letters and sounds are matched much more consistently. They are known as transparent orthographies. Say, if you take the Spanish word monte, which means mountain, it's read m-o-n-t-e, and you can read it letter by letter and get a correct, predictable result.

Because they are so consistent, having weak phonological awareness is less of an obstacle in these languages, research by Landerl and her team suggests. Children who are not that good at recognising sounds can still learn to read well in them. For example, German-speaking children with dyslexia "can read with relatively high accuracy. They are very slow at reading, but they can work it out," Landerl says.

Such slow reading can be a serious obstacle in itself, and even make children stop reading altogether, according to Landerl. But it is different from the hurdles faced by English-speaking children with dyslexia, who may not be able to identify a word at all. Research has in fact shown that an inconsistent spelling system can exacerbate some symptoms of dyslexia.

Even those of us who may think we read English well, still make a hidden effort. Eye-tracking research has shown that English adults' eyes linger more on each word, as if really trying to crack the whole unit. In transparent languages, the eyes just track the letters, and decode the words bit by bit.

English is not the only language that makes these special demands on the brain. Danish spelling is similarly inconsistent (and Danish children also take longer to learn to read, compared with children in more consistently spelled languages). French is somewhere in between, with certain predictable patterns, but also, words that just have to be memorised, such as "monsieur".

Orthographic chaos may help explain, then, why Alex struggled so much with English. But why did he connect with Japanese?

In some ways, Japanese has a more complicated writing system than English. It consists of three scripts: Hiragana, Katakana, and Kanji.

Kanji is written in characters that were originally imported from China. These characters often have a Chinese-based pronunciation, and a Japanese one. The word for "mountain", for example, is written as 山, and read as "san" (Chinese-derived) or "yama" (Japanese-based).

Alex says he finds reading Kanji much easier than reading English words, partly because you can "recognise the meaning of a character before reading it". That is to say, you can see that a character is a mountain, or a fish, or maybe it has a little fish in it, to show that it is fish-related. By contrast, in English, you need to grasp the whole word and its sound, then figure out the meaning.

Hiragana and Katakana, meanwhile, consist of signs that represent syllables. These scripts are very consistent: the Hiragana sign ね is pronounced as "ne", for example. Hiragana is the first script Japanese children are taught, Wydell says: "It's no secret that children learn to read Hiragana, and then Katakana, very easily. By the end of the first term of school, 95% of children can read and write in Hiragana."

Alex cannot even remember learning Hiragana: "It came so naturally to me." He has never struggled with it.

Finding it difficult to process sounds, as was the case with Alex, is not such a big barrier in Japanese, Wydell says. But there can still be other problems: "In Japanese, you have to be good at visual-spatial processing skills, because you have to configure all these characters in a small square," she says. "If Japanese children have problems with visual-spatial processing, they tend to show difficulties in reading and writing in Japanese," especially with Kanji characters.

In fact, a study of Cantonese-speaking children with dyslexia found that some read more fluently in English, and struggled with picture-based Chinese writing.

However, children with both a phonological and a visual-spatial processing deficit would find both English and Japanese writing difficult, Wydell says.

Because of these differences between writing systems, learning to read in two languages can offer surprising benefits.

Marie Lallier is a specialist in educational neuroscience at the Basque Center on Cognition, Brain and Language in San Sebastian, Spain. She and her team studied two groups of bilingual children in the Basque region: a French-and-Basque-speaking group on the French side of the border, and a Spanish-and-Basque-speaking group on the Spanish side. The children were learning to read in both their languages.

The researchers tested their reading skills in Basque, and in made-up words such as "umke", which the children couldn't just read by having previously memorised them, but had to decode letter by letter. They found that the children used different reading strategies, depending on whether their second language was French or Spanish.

Learning a second language very early on could be an actual help for kids with reading difficulties – Marie Lallier
Essentially, the French-Basque children used a more "French" reading style, which involves grasping words as a whole – good for French words that can't be decoded letter by letter, and also good for the familiar Basque words they already knew.

The Spanish-Basque children tended to decode the words letter by letter – which works for Spanish and Basque, since both are transparent.

Each style gave the children a different advantage.

The French-influenced, whole-word approach helped the French-Basque children read a text of familiar Basque words quickly and accurately. Even though the text was in Basque, not French, their underlying skill of remembering words helped them. "They were making fewer errors when they were reading [familiar] Basque words, compared to other group," says Lallier. "But the other group were making fewer errors when reading new [made-up] words, where you have to decode it letter by letter."

Having a second reading strategy can have other advantages, too. Another study by Lallier focused on Welsh-English bilingual adults with dyslexia, and monolingual English speakers with dyslexia. The Welsh-English bilinguals were better at decoding new words – because Welsh had given them more practice at this kind of reading strategy.

"Learning a second language very early on could be an actual help for kids with reading difficulties," says Lallier, especially if that language is transparent and boosts their decoding skills.

Speaking to Alex about his dyslexia diagnosis as a teenager, one can't help but notice another benefit of having a second language: confidence.

"Because I had the Japanese to fall back on, it was a confidence blow, but it wasn't the end of the world," he says. His attitude was: "Fine, I'm struggling, but so what, at least I can speak the language [English], and I've got another language [Japanese], that I can comfortably read in."

Today, he lives in Japan and uses both English and Japanese in daily life. He uses technology, such as spell-checkers, to avoid spelling mistakes in English. And while he finds reading in English more tiring than in Japanese, he enjoys reading books in both languages, sometimes even comparing translations. On the one hand, the fact that his formal education was not in English, and his dyslexia in English was diagnosed relatively late, meant he possibly missed out on techniques that might have helped him earlier. On the other hand, he sees an upside: "I didn’t recognise the struggle until I had good, healthy self-esteem that I could tackle it with."

BBC

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