For the study, researchers at Coventry University in the U.K., asked 195 children to complete a battery of tests to demonstrate their understanding and use of word structures and sounds. One in four participants who had reading difficulties were found to suffer from mild to moderate hearing impairment.
However, none of the parents of children with dyslexia had any clue that their children had some degree of hearing loss.
The study also found that one in three children with a history of ear infections also had problems with reading and writing.
According to lead researcher Helen Breadmore, even mild hearing loss can have a significant impact on children’s ability to pick up reading skills.
“A mild-moderate hearing loss will make the perception of speech sounds difficult, particularly in a classroom environment with background noise and other distractions,” Breadmore said. “Therefore, children who have suffered repeated ear infections and associated hearing problems have fluctuating access to different speech sounds precisely at the age when this information is crucial in the early stages of learning to read.”
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Breadmore suggested that children who struggle with reading should be tested for hearing problems more regularly.
Most Canadian provinces have programs in place to screen infants for hearing loss, according to a 2016 report by the Canadian Association of Audiology and Speech-Language Audiology Canada. But as the authors of the Coventry University study point out, deafness can take root at later ages.
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Children who are diagnosed with hearing difficulties after two years of age are likely to have lifelong issues with literacy, according to the Canadian Paediatric Society (CPS).
CPS recommends that school-aged children be taken to a hearing specialist if they display certain tell-tale signs of hearing difficulties, which include regularly needing things to be repeated, speaking loudly, turning up the volume on the TV and having trouble learning in school.