WEDNESDAY, Nov. 11 (HealthDay News) -- Students with developmental dyslexia may not be able to focus on the teacher's voice in noisy school settings that include banging lockers, scraping chairs and other auditory distractions, a U.S. study has found.
Developmental dyslexia affects reading and spelling skills in 5 to 10 percent of school-age children.
In their study, researchers from Northwestern University in Chicago found that the brains of non-dyslexic children could ignore distractions and automatically focus on relevant, predictable and repeating auditory information. Dyslexic children didn't have this ability.
These findings confirm previous research that found children with developmental dyslexia have difficulty separating relevant auditory information from competing noise. The new study also offers biological evidence that children who have difficulty hearing speech in noisy settings also have a measurable neural impairment that hampers their ability to utilize regularities in the sound environment.
"The ability to sharpen or fine-tune repeating elements is crucial to hearing speech in noise because it allows for superior 'tagging' of voice pitch, an important cue in picking out a particular voice within background noise," researcher Nina Kraus, a professor of communication sciences and neurobiology and director of the Auditory Neuroscience Laboratory at Northwestern University, said in a university news release.
Along with conventional reading- and spelling-based interventions, children with developmental dyslexia may benefit from simple approaches such as placing them in front of the teacher or using wireless technologies to enhance the sound of a teacher's voice, the researchers said.
"The study brings us closer to understanding sensory processing in children who experience difficulty excluding irrelevant noise. It provides an objective index that can help in the assessment of children with reading problems," Kraus said.
The study findings are published in the Nov. 12 issue of the journal Neuron.
The Nemours Foundation has more about dyslexia.
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