The
training program, which is designed to help dyslexics understand
rapidly changing sounds that are the building blocks of language, helped
the participants become better readers after just eight weeks.
The
findings were released Monday in "Neural deficits in children with
dyslexia ameliorated by behavioral remediation: Evidence from functional
MRI," published by the
Proceedings of the National Academy of Sciences Early Edition.
"It was very dramatic to see the huge differences that occurred in the
brains of these children," said Stanford psychology Professor John
Gabrieli, one of the study's authors. "The intervention, although
substantial, only covered eight weeks. One note of optimism about the
study is that such a limited intervention can have a substantial effect
on reading scores."
Brain imaging scans of the children who
participated in the training showed that critical areas of the brain
used for reading were activated for the first time, and that they began
to function more normally. Furthermore, additional regions of the brain
were activated in what the researchers believe the dyslexics may have
used as a compensatory process as they learned to read more fluently.
Gabrieli
said the study's findings may help demonstrate how different kinds of
reading programs can tackle various problems faced by poor readers.
"This is showing us for the first time the specific changes in the
brains of children receiving this sort of treatment, and how that is
coupled with the improvement they have in reading and language ability,"
he said. "We're hoping that this becomes an additional tool to
understand how educational remediation programs alter children's
abilities, as they must do, by changing the way their brains process
information."
Study co-author Paula Tallal, professor of
neuroscience at Rutgers University and a founder of Scientific Learning
Corporation, the Oakland-based company that designed the program, said
the findings are also important because it is the first time a
commercial product has been proven scientifically to work using
standardized educational testing and brain imaging. Scientific
Learning's computer program,
Fast ForWord Language, focuses on helping children become more fluent at processing the rapidly changing sounds, she said.
"In light of President [George W.] Bush's legislation, No Child Left
Behind, which mandates that only scientifically validated applications
be used for intervening with children, this program has the potential to
address the crisis we are facing in the number of children failing to
meet [educational] standards," she said. The No Child Left Behind Act of
2001 places an emphasis on teaching methods that have been proven
scientifically to work.
Dyslexia, sometimes called "word
blindness," is a common disorder, affecting 5 to 10 percent of
Americans, Gabrieli said. It is defined as a specific difficulty in
reading that is severe enough to interfere with academic functioning and
cannot be accounted for by lack of educational opportunities, personal
motivation or problems in sight or sound. Tallal said that studies
estimate that about 40 percent of people with dyslexia inherit it
genetically. Other factors believed to trigger the disorder include
prematurity at birth, developmental language impairment and attention
deficits, she said.
Dyslexics have trouble distinguishing between
letters that rhyme, such as 'B' and 'D.' "If you hear the sound 'ba' in
butter and 'da' in Doug, the only way we know the difference is in the
first 40 milliseconds of the onset of those sounds," Tallal explained.
"The ability to extract the sounds out of words is what is called
phonological awareness. We have to be aware that words can be broken
into sounds, called phonemes, and that these sounds have to be
identified with letters." This process might appear intuitive, but it is
a learned skill, Tallal said.
The training program the children
took part in was targeted at helping them learn to process and interpret
the very rapid sequence of sounds within words and sentences by
exaggerating and slowing them down. "These are the building blocks you
have to have in place before you can learn to read," Tallal said. "I
think
Fast ForWord is building the scaffold for reading, and
doing it based on scientific knowledge of the most efficient and
effective way of helping the brain learn."
The study
The
study included 20 dyslexic children aged 8 to 12 years. Their brains
were scanned using functional magnetic resonance imaging (fMRI) at
Stanford's Lucas Center for Magnetic Resonance Spectroscopy before and
after participating in the eight-week training program. A control group
of 12 children with normal reading abilities also had their brains
scanned but did not participate in the training.
The scanning
machines, which look like beds that slide into small tubes, normally are
used to check for brain injuries or tumors, Gabrieli said. With
slightly different software they can be used to measure which regions of
the brain are active by looking for changes in blood oxygenation, a
process that occurs in parts of the brain where the neurons are active.
Study
lead author Elise Temple, assistant professor in human development at
Cornell, headed the research as a graduate student at Stanford. Both the
dyslexic children and the control group were asked to perform a simple
rhyming task while having their brains scanned. Participants were shown
two uppercase letters and told to push a button if the two letters
rhymed with each other. For example, 'B' and 'D' would match, but not
'B' and 'K.'
Twenty-minute sessions were broken into five-minute
segments, during which the children had to stay completely still.
Afterward, they were rewarded with Pokémon or baseball cards, and given a
picture of their brain to take home. Before the sessions started,
Temple allowed the children to play around the machines, which can be
claustrophobic, to help them become comfortable with the testing
process. "In this study, it was especially important not to have the
experience be a bad one because we wanted them to come back," Temple
said.
During the rhyming exercise, children with normal reading
showed activity in both the language-critical left frontal and temporal
regions of the brain, the latter of which is behind and above the left
ear. Dyslexics, however, struggled with the task and failed to activate
the temporal region, and showed some activity only in the frontal brain
area.
Afterward, the dyslexic children used the
Fast ForWord Language
computer program for 100 minutes a day, five days a week, as part of
their regular school day. "The computer games were fun, the kids liked
them," Gabrieli said. The program consisted of seven exercises that
rewarded players when they answered questions correctly. For example,
when a picture of a boy and a toy was shown, a voice from the computer
would ask the player to point to the boy, a step that required
understanding the very brief difference in the sound of the first
consonant in each word. Initially, the questions were asked in a slower,
more exaggerated fashion than in normal speech to help the children
understand the sounds inside the words. As the player progressed, the
speed of the voice in the program slowly increased. "Each child worked
at his or her own level," Tallal said. "The goal was to leave all
children processing sounds correctly in words and sentences of
increasing length and grammatical complexity."
The results
Following
the training, the dyslexic children's scores went up in a number of
language and reading tests, Gabrieli said. "The study supported the idea
that for some children, getting training on just simply processing
rapid sounds is a route to becoming much more fluent and capable
readers," he said. In addition, activation of the children's brains
fundamentally changed, becoming much more like that of good readers. "We
see that the brains of these children are remarkably plastic and
adaptive, and it makes us hopeful that the best language intervention
programs in the future can alter the brains in fundamentally helpful
ways," he said.
It is likely that the children will continue to
need considerable help in reading, Gabrieli said. "This is not a
one-shot vaccine," he said. "But it makes them much more prepared to
take advantage of a regular curriculum to read successfully and do
well."
The next step, Temple said, is to see if other commercial
programs can alter the brain as well. "I don't know if these changes are
unique to this program," she said. "Are there some training programs
that are better for some kids than others?" A future goal would be to
offer a series of tests to help select which programs best meet a
child's needs, she said.
For many years, Gabrieli said, the nation
has been concerned with the best methods to teach reading. "We're
hoping that this becomes one piece of many pieces of research that will
help us better understand ... what are effective ways to rescue children
who have trouble reading," he said. In addition, the study brings the
scientific use of brain imaging into the arena of education. "We'd like
to use these cutting-edge tools of neuroscience to somehow directly
assist thoughts about educational curricula, policies and ways to help
children perform better in school and look forward to better futures,"
he said.
In addition to Temple, Tallal and
Gabrieli, the paper was written by Gayle K. Deutsch, a senior clinical
scientist at Stanford; Russell Poldrack, a former postdoctoral student
at Stanford and currently assistant professor of psychology at the
University of California-Los Angeles; Steven L. Miller of Scientific
Learning Corporation; and Michael M. Merzenich, a founder of Scientific
Learning and a professor at the University of California-San Francisco.
The Haan Foundation for Children helped fund the study.
as young as age 3 carry objective neurophysiological markers that signal whether they will struggle to read. Children so young have never been tested before, but the research team found a way to measure their brain responses to sound, a key part of pre-reading development.