In a comment on a recent post about auditory processing Alan Coady remarks on the differences inherent in learning Chinese. I have just read a bit around the subjexct but cannot claim to grasp all the implications. Here goes:

There are very real differences in how dyslexia manifests itself in different languages, says Maryanne Wolf whose important book I have mentioned before.

Depending on what is emphasised in any given language (fluency in German, visual spatial memory in Chinese, phonological skills in English), there will be somewhat different faces of dyslexia, as well as different predictors of reading failure. Different writing systems make somewhat different uses of the major structures involved in the reading circuit.

There is a suggestion from researchers at the University of Hong Kong that dyslexia may be more even complex in children speaking Chinese than English. In Chinese dyslexia, disordered phonological processing may coexist with abnormal visual spatial processing. In the study, scans showed that activation in a portion of the brain known to mediate visual spatial processing was weaker in those with dyslexia than in those who do not find reading a challenge.

The fact that Chinese and Western dyslexics show structural abnormalities in different brain regions suggests that dyslexia may even be two different brain disorders in the two streams of culture.

While alphabetic languages like English were learnt using letter-to-sound conversion rules, pronunciations in a non-alphabetic, logographic language like written Chinese must be memorised by rote.

The part of the brain affected in western learners with dyslexia is responsible for letter – sound conversion, However, the region for Chinese is close to the region for motor skills. So, learning to read and write Chinese puts even greater demands on learners with dyslexia who have an auditory processing difficulty – generally accepted as the most significant characteristic in the majority of learners with dyslexia.

I think this means that for those in the west with visual and auditory processing difficulties the challenges are not dissimilar to the problems encountered by Chinese students with this specific difficulties.

Wolf concludes that learning to read Chinese requires a strong right hemisphere (present in many learners with dyslexia) because of the numerous, visually demanding logographic characters.  

The remarkable rapidity and efficiency achieved by (non-dyslexic) Chinese is on display in brain images of modern Chinese readers. These images show the brain’s vast capacity for visual specialisation when both hemispheres are recruited in reading all of the many characters. The Chinese readers’ fluency is one proof that efficiency is not reserved for alphabet readers alone.

Wolf refers to a fascinating early bilingual case study showing clear differential use of hemispheres.

A bilingual businessman, proficient in English and Chinese, suffered a severe stroke. He lost his ability to read Chinese, but could still read English. This is because the brain can be differentially organised for different writing systems.

Not only are different pathways utilised by readers of Chinese and English, but different routes can be used within the same brain for reading different types of script. And because of the brain’s prodigious ability to adapt its design, the reader can become efficient in 2 very different languages.

There are multiple pathways to fluent comprehension and reading in any language.

But do Chinese readers develop visual skills because of their alphabet? We know that practice means neurological pathways grow and extend exponentially. Do we, with our left hemisphere dominant education system disproportionately reward learners with strengths in responding to auditory stimuli (a teacher’s chalk and talk, stress on phonics in the early stages of acquiring literacy) and rapid information processing (the Hare rather than the Tortoise)? 

My brain hurts. I’d welcome comments to help me clarify this.