Brain Shown
To Change As Dyslexics Learn
A novel treatment for dyslexia not only helps children improve their reading skills
but also shows that the brain changes as dyslexics learn, according to a study
by an interdisciplinary team of University of Washington scientists.
The research, published in the current issue of the
Journal of Neuroradiology, also provides new evidence that dyslexia is a treatable
brain-based disorder, according to microphysicists Todd Richards and neuropsychologist
Virginia Berninger, who headed the UW research team.
Dyslexia, which is a reading disorder and the most common learning disability,
affects an estimated 5 percent to 15 percent of children. Contrary to popular
myth, the hallmarks of the disorder are subtle deficits in oral language processing
of the sounds of the language, not reversal of letters.
"We want to make it very clear that we didn't cure dyslexia, but we think we effectively
treated it," said Berninger. "Because of differences in their brains, the boys
in our study will need additional educational treatment if they are to continue
developing their reading skills. There are no quick fixes or magic bullets for
curing dyslexia." Richards and Berninger
said the new study is the first in a line of research that will explore the degree
to which the brain affects ease of learning and, in turn, is affected by specific
educational interventions. They expect
this kind of research will build a foundation that educators can draw upon to
improve the accountability of teaching practices.
"Some children learn to read easier than others, and unless there is real brain
damage, the brain will change as children learn," said Berninger. "Dyslexia is
not brain damage. There are just differences in the wiring of the brain for those
parts that are involved in reading. "There
is no such thing as a perfect brain. Any brain probably has structural anomalies.
With appropriate instruction, dyslexic brains may become more efficient at processing
the sounds of language. Because they are more efficient they use less brain area
and metabolic energy." Complete details
about the intervention program -- a three-week reading and science workshop developed
by Berninger -- will be published next fall in the journal Learning Disability
Quarterly. The intervention draws on elements
of existing treatments, putting them together in a novel way.
In the workshop, the boys were taught to analyze sound in spoken words, to attach
sounds to letters automatically and to use different strategies for translating
written words into spoken words. The treatment
was novel in that it took advantage of the boys' talent and interest in science
and technology. It linked reading instruction with a hands-on science workshop
that used materials from Seattle's Pacific Science Center. The workshop is only
one of a number of dyslexic treatments being developed at the UW.
The current study builds on previous UW research showing that there are chemical
differences in brain function of dyslexic and non-dyslexic children during sound
processing tasks. Fifteen boys -- eight
dyslexics and seven non-dyslexics -- were involved in the new study. The boys
ranged in age from 10 to 13 years and the dyslexic and control groups were matched
for age, IQ and head size, but not in reading skills.
The controls were above average readers for their age and learned to read very
easily. The dyslexics had delayed reading skills and were reading well below average
for their age group. They also had a family history of multi-generational dyslexia.
Both groups underwent spectroscopic imaging at
the beginning of the study. The dyslexic boys then entered the treatment program
that was designed to improve their phonological abilities or skills in understanding
and using the sounds of language. About
a year after the first imaging session, the dyslexics' reading skills were tested
and both groups were imaged again using the same tests to evaluate the long-term
effect of the treatment. Following treatment,
the dyslexics expended 1.8 times the energy to do the same sound-processing task
as the controls, compared to about 4 times the energy before treatment.
According to Richards, the dyslexics and controls
were not statistically different after treatment. Over this same period, the dyslexics
also made large strides in their reading ability, especially in sounding out new
words. "The relative gains they made compared
to children of the same age were more than what would be expected for the time
that passed between tests," added Berninger. They made significant gains in analyzing
sounds needed to decode words and in sounding out unknown words. After the workshop,
all but one of the boys could read grade appropriate passages.
"This research offers a message of hope. We can see improvement in children's
reading levels with this intervention even if there are preexisting brain differences
that make learning difficult. "Parents
of the boys in the study told us that children who didn't read independently before
are now picking up books on their own and reading them."
The new results are part of a larger UW effort to understand the basis of dyslexia
and develop treatments for the disorder. The National Institute of Child Health
and Human Development funds the research and the UW's multidisciplinary Learning
Disabilities Center. The center does not
offer a summer treatment program to the general public. Treatment studies are
only open to children of families participating in the dyslexia family genetics
and brain imaging project. Other members
of the UW research team and co-authors of the study are David Corina, associate
professor of psychology; Stephen Dager, professor of psychiatry and behavioral
science; Robert Abbott, professor of educational psychology; Kenneth Maravilla,
professor of radiology; and Ken Marro, a postdoctoral researcher in radiology.
In addition, UW doctoral students Sandra Serafini
and Keith Steury and radiology technician Denise Echelard participated in the
research. With thanks to UniSci - the excellent
Daily University Science News. |