Thursday, August 4th, 2011
Dyslexia, the learning disability that affects reading and spelling skills for an estimated 15-20 percent of the American population, may have an auditory component, a new study has found. The findings could have implications for how dyslexic children are taught in school. The New York Times reports:
A study published last week in the journal Science suggests that how dyslexics hear language may be more important than previously realized. Researchers at the Massachusetts Institute of Technology have found that people with dyslexia have more trouble recognizing voices than those without dyslexia.
John Gabrieli, a professor of cognitive neuroscience, and Tyler Perrachione, a graduate student, asked people with and without dyslexia to listen to recorded voices paired with cartoon avatars on computer screens. The subjects tried matching the voices to the correct avatars speaking English and then an unfamiliar language, Mandarin.
Nondyslexics matched voices to avatars correctly almost 70 percent of the time when the language was English and half the time when the language was Mandarin. But people with dyslexia were able to do so only half the time, whether the language was English or Mandarin. Experts not involved in the study said that was a striking disparity.
“Typically, you see big differences in reading, but there are just subtle general differences between individuals who are afflicted with dyslexia and individuals who aren’t on a wide variety of tests,” said Richard Wagner, a psychology professor at Florida State University. “This effect was really large.”
Dr. Sally Shaywitz, a director of the Center for Dyslexia and Creativity at Yale University, said the study “demonstrates the centrality of spoken language in dyslexia — that it’s not a problem in meaning, but in getting to the sounds of speech.”
That is why dyslexic children often misspeak, she said, citing two examples drawn from real life. “A child at Fenway Park watching the Red Sox said, ‘Oh, I’m thirsty. Can we go to the confession stand?,’ ” she said.