Dyslexia is a developmental reading disorder that happens when the brain has a hard time processing language.

However, it may not be poor eyesight that causes children to misread letters and words.

A new study has found that, contrary to prior thought, dyslexic children often have perfect vision.

In the study published in the journal Pediatrics, researchers from the United Kingdom report that 80 percent of children with dyslexia had perfect eyesight.

Get the Facts: What Is Dyslexia? »

Children Underwent a Variety of Tests

Researchers collected data on 172 children between the ages of 7 and 9 who had a severe reading impairment. That data was compared to information from 5,500 children of similar ages without dyslexia. 

The dyslexic study participants were predominantly male, underweight at birth, had mothers who smoked, and were of low socioeconomic status. 

The tests included probes into sensory and motor fusion, and stereoacuity. 

Vision-based therapies and support are often offered for children with dyslexia, but these findings suggest that visual impairment may not be as prevalent as previously thought.

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Separating Vision from Other Factors

Proponents of separating vision problems from dyslexia have been gaining momentum in the past few years. 

Learning disabilities affect 2.6 million children in the United States between the ages of 6 and 11, according to a policy statement published in the American Academy of Pediatrics in 2009. But learning disabilities are complex and therefore require complex solutions.

“Children with suspected learning disabilities should receive only individualized, evidence-based diagnostic and educational intervention combined with psychological, medical, and vision-oriented treatments as needed,” the statement said.

What the new study further supports is that treatments for dyslexia shouldn’t be a catchall. Another article, published in Pediatricsin 2011, found that there wasn’t adequate research to support claims that vision problems were directly related to dyslexia. 

Dyslexia tends to run in families, and the exact cause is unknown. Therefore, treatment shouldn’t necessarily be the same for each patient. 

“This new analysis adds to the evidence that visual impairment is not a factor in dyslexia,” said a statement about the new study. “Although vision-based therapies and support are offered for children with dyslexia, the scientific basis for these is disputed, and most studies are small, involving few children.”

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