Study produces new dyslexia findings

EVANSTON, Ill., Nov. 11 (UPI) -- Northwestern University researchers say they've determined dyslexic children might have difficulty concentrating in noisy situations.

The scientists said the majority of school-aged children can focus on the voice of a teacher despite the normal ambient noise of a classroom thanks to their brain automatically focusing on relevant, predictable and repeating auditory information.

But the researchers found students with developmental dyslexia -- a neurological disorder affecting up to 10 percent of school-aged children -- might find the teacher's voice becomes lost in the background noise of banging lockers, whispering children, playground screams and scraping chairs.

The scientists said they also produced biological evidence that dyslexic children who report problems hearing speech in noisy environments might suffer from a measurable neural impairment that adversely affects the ability to make use of 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," Professor Nina Kraus, who led the study, said.

The research from Northwestern University's Auditory Neuroscience Laboratory that included Bharath Chandrasekaran, Jane Hornickel, Erika Skoe and Trent Nicol appears in the Nov. 12 issue of the journal Neuron.