Recent research using fMRI reveals differences in brain functioning between some pre-readers with a family history of dyslexia and pre-readers with no such family history. Two groups of children, average age 5 1/2, matched for age, sex, and iq, consisted of 36 at-risk pre-schoolers and 18 preschoolers with no known risk. Compared with the control group, some children at risk for dyslexia showed reduced activity in the brain's occipitotemporal and left temporoparietal regions. This is similar to older children and adults with dyslexia. High activations in these regions--in both the at-risk and control groups--correlated with better performance on tasks that predict reading ability, such as rhyming, knowing letters and letter sounds, and being able to separate sounds within a word.
Early diagnostic markers could potentially enable a child to receive early interventions to head off difficulties and frustration in school, say investigators Nora Raschle, PhD, and Nadine Gaab, PhD, researchers from the Laboratories of Cognitive Neuroscience at Boston Children's Hospital (PNAS, January 23). Developmental dyslexia, which affects 5 to 17 percent of children, has a strong familial component. Up to half of all children with a positive family history will have dyslexia themselves. This study reveals differences in brain activity even before children begin reading instruction.
Drs. Gabb and Raschle are conducting further research to see if the fMRI observations correlate with diagnosed dyslexia and with EEG results.
Article: Research: Spotting Dyslexia In Pre-readers, Boston Children's Hospital http://www.childrenshospital.org/views/april12/spotting_dyslexia.html
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