Alan’s parents are English, but he was born and grew up in Japan. He would pass as a native speaker of either language. What brought Alan to the notice of Taeko Wydell, an expert on Japanese reading, and Brian Butterworth, was that he was severely dyslexic, but only in one language. In the other, he was probably in the top 10% of readers of his age.
New research by US and Chinese scientists challenges our interpretation of how it is possible to be dyslexic in one language but not another. It shows that readers of Chinese use a different part of their brains to readers of English.
The study, led by Li Hai Tan and reported in Nature, may unexpectedly tell us some key things about how dyslexia affects the brain. Brain functioning, and indeed structure, is moulded by experience. Learning a regular spelling system such as Italian creates differences in brain organisation compared to learning highly irregular English. Italian has 26 rules to learn, which takes about six months; English takes longer because there are many irregularities (and several hundred rules). In Chinese 3,500 characters are needed to read the equivalent of the Daily Mail and about 6,000 characters to read books.
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Mandarin Immersion Parents Council 
Dear Ms. Weise,
I find your article about Alan very interesting but an hypothesis comes to my mind.
No reader only reads through his/her phonological route as after a while a visual route develops. This visual route might not be impaired, despite the phonological one not being properly efficient, but might not develop because the word (being read via the phonological route first) is being deciphered wrongly or differently every time and so it is like not being exposed many times to the same word.
When dyslexic children are being offered proper stimulation of that visual route, on top of phonological awareness help, it is very clear that the visual route can become efficient and becomes a good way of reading, avoiding the difficulties linked to poor phonological skills, even with children that still have major phonological difficulties.
Consequently, my idea is: is it possible that Chinese reading only involves that visual route?
Alan being dyslexic in English and not in Chinese would therefore means that his visual route is very efficient?
Remediation in English might then rely more on using “sight words” and less on phonological awareness with very good results.
Yours sincerely,
L. J.