| Brain
Scans Used to Find Dyslexia Clues.
Nine-year-old
Patrick Price bounced up to the huge MRI machine, a powerful brain scanner disguised
by drapes to resemble a kid-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, says Georgetown University
neuroscientist Guinevere Eden. "Getting information on what works, it's hard.
Families go through four and five programs. They
mortgage their houses," says Eden, who directs Georgetown's Center for the Study
of Learning. "It's a vulnerable population." 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," says 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. It's often hereditary, and spotting dyslexia early is important
to helping children succeed in school. 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. Right
brain, left brain.
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. Her findings
validated a theory proposed in 1925 by dyslexia pioneer Samuel Orton: Normally,
youngsters depend more on the visually oriented right side of the brain at first,
perhaps interpreting words as if they were pictures. As reading matures, the brain's
language-linked left side grows to dominate, and visual stimulation is suppressed.
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. Half
the children in this experiment are like Patrick, from a dyslexia-only private
school near Baltimore that provides intense, specialized reading instruction.
Eden hopes to recruit
the other half from Baltimore public schools. After initial brain scanning, all
the kids will get, for free, $3,000 worth of a commercial dyslexia reading program
-- one-on-one tutoring using a phonology approach and a multisensory approach.
For the study's control
phase, they also get math training, to make sure simple extra attention isn't
a placebo effect that temporarily boosts reading ability. 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 says. So she sends them home with brain
pictures and stickers. "That's
my brain?" marvels Patrick, staring at images from the scanner as researchers
show him his own cortex. "Wow!" " Original
article. With
many thanks to the highly recommended CNN.

|