Brain Scans Predict Dyslexia Improvements
Reading Skills Get Better in Kids Who Compensate Using Specific Area of Brain
Dec. 20, 2010 -- Scientists using brain scanning technologies say they have been able to predict with 90% accuracy which children with dyslexia will be able to improve reading skills over a period of a few years.
Researchers say their findings reveal activity in specific brain regions during reading that could eventually lead to new treatments for people with dyslexia.
“At this time, we cannot say which treatment type will each child benefit from,” study researcher Fumiko Hoeft, MD, PhD, an imaging expert at Stanford University, tells WebMD in an email. “But with more research, and if researchers combine it with intervention studies, then we should be able to identify brain patterns that are predictive of responding to one type of intervention or another.”
She says in a news release that the study “gives us hope that we can identify which children might get better over time” and that the findings represent “a huge step forward.”
The discovery of brain regions involved in the learning disorder “may provide a mechanism for enduring improvement that promotes relatively successful reading development,” according to the study, published in the Dec. 20 issue of the Proceedings of the National Academy of Sciences.
Study Suggests Interventions to Help Dyslexics Learn to Read
Dyslexia is a learning disability that impairs a person’s ability to read and affects 5% to 17% of children in the U.S. About 20% of youths with dyslexia develop adequate reading skills by the time they are adults.
But until now, what happens in the brain that permits improvement has not been known, the researchers say.
Brain imaging studies in the past have shown greater activation of specific brain regions in children and adults with dyslexia while they are performing reading-related tasks. In particular, an area known as the interior frontal gyrus seems to be hyperactivated in dyslexic people.
Hoeft and colleagues set out to determine whether neuroimaging could predict which children with dyslexia would gain improvement in reading skills, using functional magnetic resonance imaging (fMRI ), which shows oxygen use by areas in the brain, and diffusion tensor magnetic resonance imaging (DTI), which shows connections between brain areas.
Study Involves Youths With Dyslexia and Normal Readers
For the study, the researchers enrolled 25 children with dyslexia and 20 without, all between ages 11 and 14, and evaluated their reading skills using standardized tests.
They used the two types of brain imaging -- fMRIs and DTIs -- observing the brains of the youths while they read.
Then, 2.5 years later, they re-evaluated reading performance. They found that no behavioral measure, including standardized reading and language tests, reliably predicted reading gains.
But the children with dyslexia who showed greater activation in the right inferior frontal gyrus showed greater improvement over the 2.5 years from the study’s start. The scientists also examined white matter connected to the right frontal region, and children in whom this was better organized also showed improvement.