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MONDAY, July 21, 2003 (HealthDayNews) -- After only three weeks of intense, specialized reading instruction, dyslexic children started to exhibit brain activity patterns that matched those seen in normal readers.
The significance of the findings is twofold: Not only does this particular type of instruction appear to be effective, but the study authors were able to see that children with dyslexia were using the same regions of their brains as other readers.
The findings appear in the July 22 issue of Neurology.
"We know the brain has to change when it learns, but to actually see the activation differences is quite striking," says Gordon Sherman, executive director of the Newgrange School and Educational Outreach Center in Princeton, N.J.
Dyslexia is the most common learning disability and may affect 15 percent or more of school-age children in the United States. Children with dyslexia have difficult learning to read and spell words. Specifically, people with dyslexia have trouble understanding language sounds, recognizing the meaning of words and spelling. Researchers have believed these difficulties may arise because people with dyslexia process language information in a different area of the brain than people without dyslexia.
Recent research also points to the role of morphology (how the parts of a word contribute to its meaning) in dyslexia.
The current study was designed to compare how morphologic and phonologic processing activates the brain. Phonology refers to correlating the sound of a word with its written form. The authors also wanted to see if a specific type of instruction was associated with changes in brain-activation patterns as seen on functional magnetic resonance imaging (fMRI) imaging.
Ten dyslexic children and 11 children with normal reading abilities underwent fMRI scans to map their brain activation patterns as they performed two types of reading tests. All the children were 11 or 12 years of age. At this point, the dyslexic children used the same areas of their brain to process language as the normal readers, but their activation levels were much weaker.
The dyslexic children then received three weeks of phonological and morphological instruction. With regards to morphology, for instance, the children were taught how to make a distinction between a family of words (such as "build" to "builder") and words that were not a family (such as "corn" to "corner"), explains study co-author Todd Richards, a professor of radiology at the University of Washington in Seattle.
While the interventions were based on recommendations from the National Reading Panel, the way the pieces were put together is unique, adds study co-author Virginia Berninger, director and principal investigator of the multidisciplinary Learning Disabilities Center at the University of Washington in Seattle. The center is funded by the National Institute of Child Health and Human Development (NICHD).
Both sets of children then underwent a second brain scan while again performing mental tasks. As with the first fMRI, they were asked to make a judgment about two words and whether certain letters within the words made the same sound. They were also asked whether letter patterns in words created meaningful relationships.
The second scan showed the brain-activation patterns in dyslexic children essentially matched the levels of the normal readers.
Language skills in the dyslexic group had also improved.
"It doesn't mean that in three weeks you can teach a dyslexic kid how to read or even make a significant effect, but they do see that the brain sets change," Sherman says. "It continues the momentum in trying to understand what is going on in dyslexia. It adds additional support that structured language programs that contain the components they talked about in the study are the absolute best way for teaching dyslexic children how to read. The caveat is that the earlier those programs are used, the more efficient and the more powerful they are, although they will work throughout a lifetime."
While the results do not represent a cure, the rapidity of the changes did surprise the study authors. "There was drastic improvement in the brain after only three weeks," Richards says. "I wouldn't have expected such a large improvement."
Imaging techniques are heralding in a whole new era of research into learning disabilities. "With fMRI, we are allowed to watch the brain work as they are thinking about language," Richards says.
One day, imaging may help with the toughest cases. "If we have a group of people with dyslexia and we see that one subset of this group is resistant to remediation, we could image their brains and see what is it that's different about these kids," Sherman says.
Berninger emphasizes that the results do not represent a quick fix. "I drew on a lot of knowledge about what's going on in the brain while kids are being taught how to learn and a lot of knowledge about language and reading systems," Berninger says.
It has a scientific foundation and a practical aspect. "The practical aspect is how do you go from that knowledge to implementing?" she adds. "We in the field have to do a better job of teaching teachers about these methods . . . We as researchers have a huge job ahead of us to get this information out."