THURSDAY, Nov. 3 (HealthDay News) -- A new study that found no
association between dyslexia and IQ calls into question the
widespread practice of classifying children as dyslexic based on
differences between their reading abilities and their IQ scores,
This approach, called the discrepancy model, is used by many
school systems in the United States to determine whether a student
will be provided with specialized reading instruction.
But the researchers said their findings suggest that with the
discrepancy model, children with dyslexia and lower-than-average IQ
scores may not be classified as learning disabled and therefore
would not be eligible for special reading help.
Dyslexia is a learning disability that affects a person's
ability to read.
In this U.S. National Institutes of Health-funded study,
researchers used MRI to measure the brain activity of 131 students,
aged 7 to 16, at schools in the Pittsburgh and San Francisco Bay
The children were divided into three groups: those with typical
reading and IQ scores; those with poor reading skills and typical
IQ scores; and poor readers with low IQ scores.
The brain scans were conducted while the children looked at
pairs of words and indicated whether they rhymed or did not rhyme.
The results showed that children with dyslexia had the same
patterns of brain activation as those without dyslexia, regardless
of whether or not they had low IQ scores in relation to their
"These findings suggest there is little reason to rely on the discrepancy model in the classroom any longer," study author Dr. Fumiko Hoeft, of Stanford University, said in an NIH news release. "Regardless of IQ, all children with dyslexia should be eligible for support in learning to read."
The study was recently published online in the journal
The findings "indicate that the discrepancy model is not a valid
basis for allocating special educational services in reading,"
Brett Miller, director of the Reading, Writing and Related Learning
Disabilities Program at the U.S. National Institute of Child Health
and Human Development, said in the news release. "It follows that,
whether they have high IQ scores or low IQ scores, children with
great difficulty in learning to read stand to benefit from
educational services to help them learn to read."
The U.S. National Institute of Neurological Disorders and Stroke
has more about