These findings indicate 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.
Dyslexic children in this study had above average intelligence but scored approximately 30 percent lower than average on standard reading tests. The dyslexic children 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 principles outlined by the National Reading Panel (http://www.
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.
Both dyslexic children and normal readers used the same specific parts of their brains to perform these tasks, says lead study author Elizabeth Aylward, PhD, with the department of radiology at the University of Washington in Seattle. However, the activation of these regions was much weaker in dyslexic children, reflecting their poorer performance on these tasks.
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.
Reading and spelling disabilities, which occur despite normal intelligence, affect 10 to 15 percent of school-age children in the United States. Early diagnosis and proper instruction 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.
The American Academy of Neurology, an association of more than 18,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as stroke, Alzheimer's disease, epilepsy, Parkinson's disease, autism and multiple sclerosis.
For more information about the American Academy of Neurology, visit its web site at http://www.