Neuroimaging ‘predicts’ which dyslexics will learn to read

WASHINGTON - Stanford University researchers have used brain imaging to predict with 90 percent precision which teenagers with dyslexia would improve their reading skills over time.

Their study, the first to identify specific brain mechanisms involved in a person’s ability to overcome reading difficulties, could lead to new interventions to help dyslexics better learn to read.

For this study, Fumiko Hoeft of the Stanford’s Center for Interdisciplinary Brain Sciences Research and colleagues aimed to determine whether neuroimaging could predict reading improvement and how brain-based measures compared with conventional educational measures.

The researchers gathered 25 children with dyslexia and 20 children with typical reading skills - all around age 14 - and assessed their reading with standardized tests.

They then used two types of imaging, functional magnetic resonance imaging and diffusion tensor imaging (a specialized form of MRI), as the children performed reading tasks.

Two-and-a-half years later, they reassessed reading performance and asked which brain image or standardized reading measures taken at baseline predicted how much the child’s reading skills would improve over time.

What the researchers found was that no behavioural measure, including widely used standardized reading and language tests, reliably predicted reading gains.

But children with dyslexia who at baseline showed greater activation in the right inferior frontal gyrus during a specific task and whose white matter connected to this right frontal region was better organized showed greater reading improvement over the next two-and-a-half years.

The researchers also found that looking at patterns of activation across the whole brain allowed them to very accurately predict future reading gains in the children with dyslexia.

Meanwhile, these findings have suggested that, after additional study, brain imaging could be used as a prognostic tool to predict reading improvement in dyslexic children.

The other exciting implication, Hoeft said, involves therapy. The research shows that gains in reading for dyslexic children involve different neural mechanisms and pathways than those for typically developing children.

By understanding this, researchers could develop interventions that focus on the appropriate regions of the brain and that are, in turn, more effective at improving a child’s reading skills.

The study was published in the Proceedings of the National Academy of Sciences. (ANI)