New Clues Point to Possible Dyslexia Cure
WebMD News Archive
Dec. 5, 2000 -- In this day and age, dyslexia is a common term, but what's really known about it, and do doctors really know how to treat it? A new study may help point the way.
Dyslexics may have difficulty with reading, spelling, understanding language they hear, or expressing themselves clearly through the spoken word or in writing. Dyslexia can hamper a person's success -- both at school and in the workplace. Moreover, about 5-17% of school-age children have the disorder.
Although we read with our eyes, reading problems associated with dyslexia may be more related to difficulty in recognizing or understanding rapidly changing sounds, according to this new research published in the Dec. 5, 2000 issue of the Proceedings of the Natural Academy of Sciences.
Learning how to read involves hearing as well as vision, and is closely linked to spoken speech. This explains why children learning to read -- or poor readers of any age -- move their lips when they read silently.
"Even though reading is primarily a visual activity, we've known for a long time that children and adults with dyslexia have problems processing language that they hear," says Gabrieli. "That impairment gives them a poor framework on which to build reading skills."
While the part of the brain normally involved in this type of hearing task was much less active in dyslexic readers, brain activity and performance on the hearing task improved in two of three dyslexic readers who took part in a rigorous training program.
"Humans are not born knowing how to read -- they need to be trained over a period of many years, far longer than it takes for them to understand spoken speech," researcher John D. Gabrieli, PhD, an associate professor of psychology at Stanford University, tells WebMD.
To study brain activity in dyslexics, Gabrieli and his colleagues used functional MRI scans to highlight those areas of the brain that are most active while performing a mental task.
"Functional MRI makes it possible to define activated brain areas very precisely," Teija Kujala, PhD, a professor of psychology at the University of Helsinki in Finland, tells WebMD. Kujala was not involved in the study.