Tuesday, September 4, 2007

A treatment for dyslexia?

Using fMRI, researchers at UW's Learning Disabilities Center are studying brain connectivity timing for dyslexia.

Science Daily: "Some brain regions are too strongly connected functionally in children with dyslexia when they are deciding which sounds go with which letters," said Todd Richards, a UW neuroimaging scientist and lead author of a study published in the current issue of the Journal of Neurolinguistics. We had hints in previous studies that the ability to decode novel words improves when a specific brain region in the right hemisphere decreases in activation. This study suggests that the deactivation may result in a disconnection in time from the comparable region in the left hemisphere, which in turn leads to improved reading. Reading requires sequential as well as simultaneous processes."

So they studied a group of dyslexic kids, and a group of 'good readers'. Amazingly,

The children's brains were scanned and then those with dyslexia participated in a three-week program that taught the children the code for connecting letters and sounds with an emphasis on timing. Then the children's brains were scanned again.
Following the treatment, the fMRI scans showed that the patterns of temporal connectivity in brains of the dyslexic children had normalized and were similar to those of the good readers and spellers.

The study has shown these gains sustained for up to 2 years so far, but stresses this is not yet a cure for dyslexia. At least they're off to a good start.
How is this happening? They hypothesize:

"These results might mean that after special teaching the children with dyslexia activated letters in written words first and then switched to sounds in spoken words rather than simultaneously activating both letters and sounds," said Richards. "The overconnection between the language conductor and working memory at the same time may be a signal that working memory is overtaxed. When language processing is more efficient after treatment, working memory does not have to work as hard.


hayesatlbch said...

There is no information given as to what the benefits are as far as reading is concerned.

Seems to me that if a follow up at 2 years was planned then it should have included a reading skills base line and show the improvement at 2 years to indicate a relationship to dyslexia.

I find it hard to believe that there were positive results as far as reading skills were concerned and not reported.

Dyslexia research is difficult but that is no reason to infer positive results.If this magic training changed a dyslexic's brain to function the same way as a nondyslexic's brain then there should have been dramatic increases in reading skills over the 2 year period.

I seldom question research results but these results are very different than any other fMRI results that have been published.

First of all you could conclude from the report that they saw the differences looked at in all the dyslexics tested. This would lead you to conclude that they have identified a way to identify if someone is dyslexic or not. This is in sharp contrast to all prior fMRI studies that have only been able to see differences in groups of dyslexics and not individuals because of overlap of results.

The 2 year follow up without any information about how the training improved reading is a real red flag. There are only a couple of possibilities. It wasn't included in the study or the results were negative and weren't reported. I can't believe there were positive increases in reading skills not reported.

In my opinion the report is misleading, poorly done or poorly reported.

John Hayes

Janie said...

A very good point. I'd love to see the actual text of the whole study to judge for myself, though I am glad to see this sort of research making strides and headlines...now if they could just follow up...