Tuesday, January 24, 2012

Brain scans spot early signs of dyslexia


Instead of waiting for a child to experience reading delays, scientists now say they can identify the reading problem even before children start school, long before they become labeled as poor students and begin to lose confidence in themselves.

Although typically diagnosed during the second or third grade of school - around age 7 or 8 - a team from Children's Hospital Boston said they could see signs of the disease on brain scans in children as early as 4 and 5, a time when studies show children are best able to respond to interventions.

"We call it the dyslexia paradox," said Nadine Gaab of the Laboratories of Cognitive Neuroscience at Children's, whose study was published in Proceedings of the National Academy of Sciences.

Gaab said most children are not diagnosed until third grade, but interventions work best in younger children, hopefully before they begin to learn to read.

"Often, by the time they get a diagnosis, they usually have experienced three years of peers telling them they are stupid, parents telling them they are lazy. We know they have reduced self esteem. They are really struggling," Gaab said in a telephone interview.

Her study builds on an emerging understanding of dyslexia as a problem with recognizing and manipulating the individual sounds that form language, which is known as phonological processing.

In order to read, children must map the sounds of spoken language onto specific letters that make up words. Children with dyslexia struggle with this mapping process.

"The beauty is spoken language can present before written language so people can look for symptoms," said Dr. Sally Shaywitz, a director of the Center for Dyslexia and Creativity at Yale University.

Signs of early dyslexia might include difficulty with rhyming, mispronouncing words or confusing similar-sounding words.