MRIs part of effort to find best teaching methods for dyslexics

WASHINGTON -- Nine-year-old Patrick Price bounced up to the huge MRI machine, a powerful brain scanner disguised by drapes to resemble a child-friendly castle. Inside, he lay nearly motionless as words and symbols flashed on a screen before his eyes.

Patrick is one of 80 Maryland youngsters with the reading disability dyslexia who are letting scientists peer inside their brains. The goal: to learn just what goes wrong when dyslexic children try to read and whether certain commercial teaching methods can make the brain rewire itself to read better.

While specially crafted instruction clearly helps dyslexic children become successful readers, there's little proof of how many of the expensive programs work, said Georgetown University neuroscientist Guinevere Eden.

"Getting information on what works, it's hard. Families go through four and five programs. They mortgage their houses," said Eden, who directs Georgetown's Center for the Study of Learning.

Consumer issues aside, exactly what brain areas are activated when a dyslexic child processes words remains a question. Competing theories are driving different approaches to treatment, making it important to understand the disorder's complex neurologic underpinnings.

"It's pretty critical work," said G. Reid Lyon of the National Institute of Child Health and Human Development, a division of the National Institutes of Health that is financing Eden's research.

Dyslexia is a neurologic disorder that affects 5 percent to 15 percent of Americans. They have normal intelligence but find it difficult to read, spell and master other language skills.

An early clue is phonological awareness, the ability to identify and manipulate sounds separately. Quick, say "Germany" without the "m." Dyslexics have a hard time, and many instruction programs aim to improve speech-sound awareness.

But dyslexic readers also tend to be more visually oriented than normal readers, so some instruction programs are multisensory.

Eden is trying to piece together multiple brain pathways in dyslexia and to prove whether what NIH's Lyon calls their "physiologic signature" truly normalizes after different interventions at different ages.

First, Eden studied readers without dyslexia to document developmental changes required for reading that begin in early school years.

Now she's examining dyslexic brains, using a noninvasive scanner that tells what neurons are activated during reading attempts by measuring their changing oxygen levels.

Inside this "functional MRI," Patrick watches a screen flashing a mix of real words and unreadable symbols. His orders: Click one button if each screen contains a tall letter or symbol, another if it doesn't.

His brain automatically tries to read the real words, meaning Eden can trace all the pathways involved. Additional exams measure other dyslexia anomalies.

In 18 months, additional MRI testing should tell what brain-level difference the extra reading programs have made and, if they have worked, which children had been most likely to benefit.

But the youngsters learn about their own brains right away through an Eden tactic designed to boost dyslexics' sometimes flagging self-esteem. "It helps kids to know something about their brain is different, is special," she said. So she sends them home with brain pictures and stickers.

"That's my brain?" marveled Patrick, staring at images from the scanner as researchers show him his own cortex. "Wow!"