August 7, 2003
Overcoming dyslexia: Brain scans show intervention makes a difference
After only three weeks of reading instruction, brain scans in children with dyslexia develop brain activation patterns that match those of normal readers, according to a new study by four UW researchers published recently in the journal Neurology.
Patricia Aylward and Todd Richards of radiology and Virginia Berninger and Jennifer Thomson of education found that children with dyslexia use the same regions of their brains as other readers, and that specialized instruction can rapidly compensate for some types of reading deficits.
The study focused on children with above average intelligence and dyslexia who had scored approximately 30 percent lower than average on standard reading tests. The children with dyslexia and a group of good readers of the same age underwent functional magnetic resonance imaging (fMRI) to map their brain activation patterns during two types of reading tests.
The children with dyslexia then received a three-week training program based on the principles outlined by the National Reading Panel convened by the National Institute of Child Health and Human Development. Both groups then underwent a second brain scan. The experiment was conducted during the summer, to avoid confounding effects from school instruction.
Both children with dyslexia and normal readers used the same specific parts of their brains to perform the reading tasks, Aylward said, but the activation of the regions was much weaker in dyslexic children, reflecting their poorer performance.
After the three-week reading program the levels of brain activation were essentially the same in the two groups. Aylward says these results indicate that instruction doesn’t “rewire” the brain of the dyslexic child, but instead strengthens the normal circuits which are already in use.
One of the most encouraging results of the study, she says, is that “we can document changes in the brain even after a fairly short training period, suggesting that appropriate in-school training has great potential for improving the reading ability of dyslexic children.”
The reading tests during the brain scan measured the ability of the children to decide whether certain letter combinations could stand for certain sounds (for example, could “ow” and “oa” make the same sound?) and whether certain letter patterns in words created meaningful relationships between words (for example, does the “er” in builder make it related to the word “build”? Does the “er” in corner make it related to the word “corn”?) Both skills are key elements of the reading process.
These are more difficult tasks for children with dyslexia. “You need to explicitly point out to dyslexics every aspect of the language,” Berninger said. “They don’t figure it out on their own. They are good at thinking, they’re intelligent, they’re creative. But when it comes to language you have to explain every aspect of it to them.
“This study shows that dyslexics are treatable,” she continued. “However, it took more intensive preplanned teaching and monitoring. It was really hard work.”
Reading and spelling disabilities, which occur despite normal intelligence, affect from 10 to 15 percent of school-age children in the United States. Early diagnosis and proper instruction have been shown to significantly improve the dyslexic child’s reading achievement outcome.
More background on dyslexia, including initial steps toward identifying it in a child, how it may be treated and additional resources can be found in Neurology’s “patient page” at http://www.neurology.org. The National Reading Panel’s principles on which the three-week training program was based can be found at http://www.nationalreadingpanel.org.
