There is no one cause for dyslexia: rather, the causes vary between languages. So conclude researchers who have found that Chinese children with reading difficulties have different brain anomalies to their Western counterparts.

The finding explains why one can be dyslexic in one language but not another. The team also hopes the work will aid the design of culturally specific strategies for learning to read and write that could benefit everyone.

People with dyslexia often find it difficult to recognize and understand words. Speakers of alphabetic languages, such as English or Russian, can have a problem converting letters into sounds. Dyslexics in these languages have reduced activity in a brain region called the left temporoparietal cortex.

But Chinese readers must learn the meanings of around 5,000 different characters, each corresponding to a word. Instead of letter-to-sound conversion problems, Chinese dyslexics have difficulties extrapolating from a symbol’s shape to its sound and meaning.

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