Why Are Some Bilingual People Dyslexic in English but Not Their Other Language?

Summary: The characteristics of language structure and writing system may explain why some bilingual people are dyslexic in English, but not in their other proficient language.

Source: Brunel University

In the English-speaking world, dyslexia is a learning disorder we’re all familiar with – if we don’t have it ourselves or have a friend or family member that struggles with it, we’re likely to have known someone at school or university who found reading and writing trickier than their peers.

n fact, more than 1 in 10 people that grew up with English as their first language are said to have dyslexia, with wide consensus pointing towards a person’s genetic history as the leading cause. One, it would appear, is either born dyslexic or not.

So, how then have we ended up with the phenomenon that some people who speak both English and another language can be dyslexic in one, but not the other?

The answer, it seems, is hidden in the characteristics of a language and its writing system.

“The English writing system is so irregular – print to sound or sound to print translation is not always one to one,” Brunel University London’s Professor of Cognitive Neuroscience, Prof Taeko Wydell, recently told the BBC radio documentary Dyslexia: Language and childhood.

“This irregularity or inconsistency makes it especially difficult for dyslexic individuals to master reading and writing in English.”

So, for example, ‘mint,’ ‘lint’ and ‘hint’ – all ‘int’ words – are pronounced differently to the word ‘pint’. And the words ‘through,’ ‘though’ and ‘tough’ all sound different, despite looking on the page like they should sound similar. This makes English a so-called ‘opaque’ language. The only way one knows the individual pronunciations, is to learn and remember each exception, such as ‘pint’ or ‘yacht,’ individually.

“This kind of irregularity doesn’t happen in other languages such as Italian, Spanish or Finnish,” said Prof Wydell, pointing to so-called ‘transparent’ languages where combinations of letters are always pronounced the same, with some rare exceptions. As such, studies have shown Italian speakers are only half as likely to show signs of dyslexia than English speakers.

Levels of dyslexia can also be far lower in countries with a symbol-based writing system, such as Japanese or Chinese, because of how those writing systems are taught in schools.

When children learn to write Japanese Kanji or Chinese characters, they consistently repeat the order of strokes required to draw each character whilst speaking aloud the corresponding word. This helps the motor sequence – the combination of small movements required to write each word or sound – get ‘wired in’ to their brains.

“So, when the child is asked to write later on, the child’s hands almost automatically write down the character from memory,” said Prof Wydell.

It’s therefore possible for people who learn to read and write in Chinese or Japanese to have no idea they have dyslexia until they later begin to learn English and are forced into reading and writing in a totally different way.

This shows a woman with her face covered in text
Levels of dyslexia can also be far lower in countries with a symbol-based writing system, such as Japanese or Chinese, because of how those writing systems are taught in schools. Image credited to Brunel University.

So low is the prevalence of diagnosed dyslexia in primary schools in Japan –  as low as 1.4% when writing with syllabic Kana characters and 6.9% when writing with Kanji characters – that it wasn’t until 2006 that Prof Wydell published STRAW-I, the first and only standardised and systematic screening test for identifying dyslexia in Japanese primary school children.

By 2013, nearly 9000 organisations across Japan were using the test, and in 2014 Prof Wydell’s work was awarded 4* ‘world-leading’ status by the UK government’s Research Excellence Framework (REF).

The test has since been extended, with the new standardized test – STRAW-R – now being suitable for children up to 15 years old, significantly increasing the chance that young people in Japan will receive a timely diagnosis for dyslexia and be able to access to the right support throughout their schooling.

About this dyslexia research news

Source: Brunel University
Credit: Tim Pilgrim – Brunel University
Image: The image is credited to Brunel University.

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  1. From my experience, English is a dog of a language, its grammar is hither and thither, its spelling and punctuation are all over the place, and I really feel sorry for a non-native speaker who has to learn it.

    I’ve never been a good speller nor a particularly good reader so reading a passage aloud in public is not something I particularly relish. On the other hand, my partner is not only an excellent reader and speller but also she can do cryptic crosswords with great ease—which is a task that’s always eluded me. (It’s always seemed pointless to me to deliberately increase the entropy of what one is saying by choosing cryptic words and meanings. One could just use clear text to avoid confusion.)

    I put my lack of ability down to both my marginal aptitude for languages and not having much interest in learning them when I was at school. (Whilst it’s possible I’m on the edge of being dyslexic I don’t consider my reading handicap sufficiently large to bother me.)

    My spelling was always worse than my grammar and the ways we were taught at school didn’t help. For instance, spelling tests were marked out of 50 instead of 100 with two marks taken off for every spelling mistake. I cannot remember the total number of words in the test but it was well in excess of 50 and that meant one could score negative marks for spelling, which I did on occasions (but I wasn’t the only one, there were also quite a few others). It seems to me that giving negative marks wasn’t the most productive way to engage students’ interest.

    There’s no doubt that words such as ‘pint’, ‘lint’, ‘through’, ‘though’, ‘thorough’, etc. are a major problem for bad spellers but it’s the sheer number of them that’s the problem, add the large number of ‘strange’ English proper names to this and we’re in big trouble. Whilst the correct punctuation of words like ‘Wycombe’ and ‘Warwick’ are comparatively well known to native speakers there are many others of that kind which aren’t—and I reckon those two words would be very problematic for those learning English as a second language.

    That long intro leads to my main point, which is to ask a question I’ve asked many times before without ever having received an even partially satisfactory answer. That being why doesn’t English use accents/diacriticals marks to help resolve many of its peculiar spellings and wayward pronunciations. It seems to me that if ever a language needs diacriticals then it has to be English. The problem of how to pronounce ‘pint’ and ‘lint’ correctly would be solved instantly if a diacritical were to be applied to one ‘i’ and not the other (for instance ‘ì’ ‘í’ or ‘î’ could be used).

    From my experience, if you ask those who are knowledgeable in English and competent in using it (such as English teachers or those who run grammar or spelling websites) about potential usefulness of using diacriticals in English then their responses are nearly always negative or at best nonchalant. As they have already mastered English without the need to resort to them, they never see any need to ponder the matter further—and those who would have actually benefited from their use have never had sufficient knowledge or wherewithal to push for their introduction, hence the complicated mess that we have today.

    Moreover, both native speakers and those with English as a second language face significant problems when they first come across written words that are not common in everyday usage. For example, I recall that I first came across the words ‘chiral’ and ‘enantiomer’ in textbooks well before I heard them being used by professionals who knew how to pronounce them correctly, again diacriticals would have quickly solved the problem. One may well ask why not consult a dictionary and use the IPA references. Correct, one can do that but if one is bad at pronunciation and spelling then one finds so many such words it becomes a never-ending tedium, thus one just skips over them none the wiser.

    It seems to me that people with dyslexia and or those who are having difficulty with pronunciation and spelling would be much better served if English used diacriticals; I base this on my own experience from having learned other languages. I studied French at school and like English, I was never particularly good at it, similarly, for some years I lived in Austria, so I’ve a smattering of German. What’s relevant here is that when I was learning French it was drummed into me that it was essential to understand the differences in pronunciation of ‘e’, ‘é’, ‘è’ and ‘ê’, etc. Thus, I’ve not much difficulty in pronouncing words like ‘d’être’ or proper nouns such as ‘Tahère’ and ‘Sainte-Sévère-sur-Indre’—a name certain cognoscenti will no doubt recognise (sorry the circumflex is missing, so three will have to suffice; right, I don’t know any names that use all four pronunciations of ‘e’). ;-)

    What I am saying is that I could mount a reasonable argument to say that my pronunciation of certain French words that contain characters with diacriticals is better than it is of many English words whose characters are missing them!

    Does anyone know if any serious work is or has been carried out with bad spellers and those with demonstrated dyslexia by training them with accented text (albeit suitably contrived for the purpose)?

    If not, then I would suggest that this might be an avenue worthy of research.

  2. A majority of the 10% quoted above as unable to read are in fact instructional casualties. They get confused when teachers teach them the wrong pronunciation of phonemes and has little if not nothing to do with opaque and transparent languages.

  3. A question and a comment. 1. It was mentioned that > 1 in 10 of those with English as their first language have dyslexia. Are you aware of papers looking at incidence of dyslexia (in English) among those in whom English was not their first language? 2. The same applies to some patients with alexia, which is an acquired condition. I am a neurologist and I remember a patient long ago who had developed an inability to read after suffering from cerebral venous thrombosis. He had settled in the USA, married a foreigner and had not used his mother tongue (Kannada) in ages. However, while awaiting consultation, he picked up a vernacular newspaper and found that he was able to read it while still unable to read English.I wondered if it was an example of Ribot’s law but a friend who is a speech pathologist suggested that the syllabic arrangement of most other languages made them easier to read without constructing larger graphemes. Other patients with ‘alexia without agraphia’ after strokes are unable to read even what they themselves have correctly written, regardless of language.

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