Posts tagged reading difficulties
Articles and news from the latest research reports.
Study First to Use Brain Scans to Forecast Early Reading Difficulties
UC San Francisco researchers have used brain scans to predict how young children learn to read, giving clinicians a possible tool to spot children with dyslexia and other reading difficulties before they experience reading challenges.
In the United States, children usually learn to read for the first time in kindergarten and become proficient readers by third grade, according to the authors. In the study, researchers examined brain scans of 38 kindergarteners as they were learning to read formally at school and tracked their white matter development until third grade. The brain’s white matter is essential for perceiving, thinking and learning.
The researchers found that the developmental course of the children’s white matter volume predicted the kindergarteners’ abilities to read.
“We show that white matter development during a critical period in a child’s life, when they start school and learn to read for the very first time, predicts how well the child ends up reading,” said Fumiko Hoeft, MD, PhD, senior author and an associate professor of child and adolescent psychiatry at UCSF, and member of the UCSF Dyslexia Center.
The research is published online in Psychological Science.
Doctors commonly use behavioral measures of reading readiness for assessments of ability. Other measures such as cognitive (i.e. IQ) ability, early linguistic skills, measures of the environment such as socio-economic status, and whether there is a family member with reading problems or dyslexia are all common early factors used to assess risk of developing reading difficulties.
“What was intriguing in this study was that brain development in regions important to reading predicted above and beyond all of these measures,” said Hoeft.
The researchers removed the effects of these commonly used assessments when doing the statistical analyses in order to assess how the white matter directly predicted future reading ability. They found that left hemisphere white matter in the temporo-parietal region just behind and above the left ear — thought to be important for language, reading and speech — was highly predictive of reading acquisition beyond effects of genetic predisposition, cognitive abilities, and environment at the outset of kindergarten. Brain scans improved prediction accuracy by 60 percent better at predicting reading difficulties than the compared to traditional assessments alone.
“Early identification and interventions are extremely important in children with dyslexia as well as most neurodevelopmental disorders,” said Hoeft. “Accumulation of research evidence such as ours may one day help us identify kids who might be at risk for dyslexia, rather than waiting for children to become poor readers and experience failure.”
According to the National Institute of Child and Human Development, as many as 15 percent of Americans have major trouble reading.
“Examining developmental changes in the brain over a critical period of reading appears to be a unique sensitive measure of variation and may add insight to our understanding of reading development in ways that brain data from one time point, and behavioral and environmental measures, cannot,” said Chelsea Myers, BS, lead author and lab manager in UCSF’s Laboratory for Educational NeuroScience. “The hope is that understanding each child’s neurocognitive profiles will help educators provide targeted and personalized education and intervention, particularly in those with special needs.”
(Source: ucsf.edu)
In Dyslexia, Less Brain Tissue Not to Blame for Reading Difficulties
In people with dyslexia, less gray matter in the brain has been linked to reading disabilities, but now new evidence suggests this is a consequence of poorer reading experiences and not the root cause of the disorder.
It has been assumed that the difference in the amount of gray matter might, in part, explain why dyslexic children have difficulties correctly and fluently mapping the sounds in words to their written counterparts during reading. But this assumption of causality has now been turned on its head.
The findings from anatomical brain studies conducted at Georgetown University Medical Center (GUMC) in the Center for the Study of Learning led by neuroscientist Guinevere Eden, DPhil, were published online today in The Journal of Neuroscience.
The study compared a group of dyslexic children with two different control groups: an age-matched group included in most previous studies, and a group of younger children who were matched at the same reading level as the children with dyslexia.
“This kind of approach allows us to control for both age as well as reading experience,” explains Eden, a professor of pediatrics at GUMC. “If the differences in brain anatomy in dyslexia were seen in comparison with both control groups, it would have suggested that reduced gray matter reflects an underlying cause of the reading deficit. But that’s not what we observed.”
The dyslexic groups showed less gray matter compared with a control group matched by age, consistent with previous findings. However, the result was not replicated when a control group matched by reading level was used as the comparison group with the dyslexics.
“This suggests that the anatomical differences reported in left hemisphere language processing regions appear to be a consequence of reading experience as opposed to a cause of dyslexia,” says Anthony Krafnick, PhD, lead author of the publication. “These results have an impact on how we interpret the previous anatomical literature on dyslexia and it suggests the use of anatomical MRI would not be a suitable way to identify children with dyslexia,” he says.
The work also helps to determine the fine line between experience-induced changes in the brain and differences that are the cause of cognitive impairment. For example, it is known from studies in illiterate people who attain reading skills as adults that this type of learning induces growth of brain matter. Similar learning-induced changes in typical readers may result in discrepancies between them and their dyslexic peers, who have not enjoyed the same reading experiences and thus have not undergone similar changes in brain structure.