Field of Science

How does the brain read?

Reading is an important skill, so it's not surprising it gets a lot of attention from researchers. Reading is an ancient skill -- at least in some parts of the world -- but not so old that we don't know when it was invented (as opposed to, for instance, basic arithmetic). And, unlike language, it appeared recently enough in most of the world that it's unlikely that evolution has had time to select for reading skill...which would explain the high prevalence of dyslexia.

Some decades ago, there was a considerable amount of debate over whether reading was phonologically based -- that is, "sounding out" is crucial (CAT -> /k/ + /{/ + /t/ -> /k{t/) -- or visual-recognition based -- that is, you simply recognize each words as a whole form (CAT -> /k{t/). People who favored the former theory emphasized phonics-based reading instruction, while the latter theory resulted in "whole language" training.

At least from where I sit, this debate has been largely resolved in favor of phonics. This isn't to say that skilled readers don't recognize some high-frequency words as whole, but it does mean that sounding out words it crucial at least in learning to read. One important piece of evidence is that "phonological awareness" -- the ability to figure out that CAT has 3 sounds by COLON has 5 or that DOG and BOG rhyme -- is just about the best predictor of reading success. That is, preschoolers who are at the bottom of the pack in terms of phonological awareness tend to in the future be at the bottom of the pack in learning to read.

At least, that is the story for writing systems like English that are alphabetic. There has been some question as to the role of phonology in learning to read character-based systems like Chinese. Two years ago, a group including Li Hai Tan of Hong Kong University presented evidence that in fact phonological awareness may not be particularly important in learning to read Chinese.

I have been trying to test one aspect of their theory for some time. Not having collaborators in China or Taiwan, I have to recruit my Chinese-speakers here in Cambridge, which is harder than you might think. The first experiment I ran took nearly six months, most of which was spent trying to recruit participants, and it was ultimately inconclusive. Last spring I piloted a Web-based version of the experiment, thinking that I might have more luck finding Chinese participants through the Internet. However, that experiment failed. I think it was too complicated and participants didn't understand what to do.

I have spent the last few months thinking the problem through, and now I have a new Web-based study. I am trying it in English first, and if it works well enough, I will write a Chinese version of the experiment. If you are interested, please try it out here.

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