Brain Scans Can Reveal Dyslexia in Preschool Children

Brain scans can show if a child has dyslexia before he or she even begins to read, a new study reported.

Dyslexia is a learning disorder that affects about ten percent of children in the U.S. The condition is mostly diagnosed around second-grade. People with dyslexia have difficulty reading despite having normal intelligence.

The present research by scientists at Massachusetts Institute of Technology (MIT) and colleagues shows that it is possible to assess the condition in its early stages. Early detection can help children with dyslexia cope with the condition, BBC reported. 

The scientists found that the condition affects a region of the brain called arcuate fasciculus. Previous research has shown that this area of the brain is poorly developed in adults who have lower reading scores when compared to adults who can read well.

"We were very interested in looking at children prior to reading instruction and whether you would see these kinds of differences," said John Gabrieli, a member of MIT's McGovern Institute for Brain Research.

The present study was based on brain scans of 40 children. Researchers mainly studied three regions of the brain known to be associated with reading skills- all located on the left side of the organ: the arcuate fasciculus, the inferior longitudinal fasciculus (ILF) and the superior longitudinal fasciculus (SLF).

Researchers found that the size and arrangement the arcuate fasciculus was associated with performance on tests of phonological awareness. These tests measure the ability to identify and manipulate the sounds of language. Strong phonological awareness has been linked with ease of reading.

 Also, the left arcuate fasciculus connects Broca's area (speech production) with Wernicke's area, (understanding written and spoken language). A larger arcuate fasciculus could help pass information from one region to another, helping children without dyslexia read easily, researchers said.

They, however, added that more studies are required to understand the reason behind the condition and if it can be treated.

"We don't know yet how it plays out over time, and that's the big question: Can we, through a combination of behavioral and brain measures, get a lot more accurate at seeing who will become a dyslexic child, with the hope that that would motivate aggressive interventions that would help these children right from the start, instead of waiting for them to fail?" Gabrieli said in a news release.

The study is published in the Journal of Neuroscience.