Dyslexia isn’t related to eyesight. Didn’t we already know that? We felt compelled to write a post that directly addresses some new research that came out in the United Kingdom and was subsequently reported by the BBC this week, causing a firestorm of supposed ah-ha moments and subsequent mudslinging. If you’re in the United Kingdom, you couldn’t have missed it, as it was all over the BBC, its affiliates, and a variety of other media outlets that picked up the story. If you live elsewhere in the world, you may not have heard yet, so let us enlighten you…
“Teams from Bristol and Newcastle universities carried out eye tests on more than 5,800 children and did not find any differences in the vision of those with dyslexia.” (BBC)
That’s right, dyslexia doesn’t have anything to do with the eyes. Big news right? Well, we’re not exactly sure why researchers thought dyslexia ever had anything to do with the eyes in the first place, given the current definition of dyslexia as “problems identifying speech sounds and learning how they relate to letters and words” (Mayo Clinic). The International Dyslexia Association defines dyslexia as a language problem, not an eyesight problem, specifying that it is “a deficit in the phonological component of language.” But nonetheless, these researchers have confirmed that the reading problems associated with dyslexia have nothing to do with eyesight.
We actually have no problem with this finding, and wholeheartedly agree, yes, dyslexia has nothing to do with poor eyesight. However, the authors of this study have made an erroneous leap (as well as a few mistaken assumptions) when they go on to suggest, “This raises doubts about the value of using coloured overlays or lenses to help dyslexic children with reading.” First, they fail to recognize that colored overlays and lenses are used to address a sensory modulation disorder known as Irlen Syndrome, not dyslexia. With Irlen Syndrome, the brain has difficulty processing the visual information it receives. They eyes work just fine, it’s the brain that has the issue and isn’t functioning properly.
Second, while it is true that a large number of individuals with reading problems that have been diagnosed as dyslexia can be helped with colored overlays and lenses, this is not because color can help dyslexia. Rather, it is because the reading problems these individuals experience have been misdiagnosed as dyslexia when in fact they are actually a result of Irlen Syndrome. It is also possible for someone to have both dyslexia and Irlen Syndrome, in which case color would help with the Irlen Syndrome but not the dyslexia, which would require different types of intervention. The important distinction here is that colored overlays and lenses will not help an individual who has only dyslexia as defined by the current parameters as a language problem related to phonological processing and connections with the written word. So, no, colored overlays and lenses will not help someone who suffers from dyslexia – technically, this is a very true statement.
Third, just because color is worn as glasses does not mean that the dysfunctional anatomy it is intended to correct are the eyes. In the United Kingdom, many Optometrists provide colored lenses to their patients. Optometrists are eyecare professionals, and their expertise is related to eyesight. It is understandable therefore that the British authors of this study would wrongly assume that because color is often prescribed by professionals who usually address eyesight problems, color is intended to correct an issue with the eyes. This interpretation is completely wrong. Colored lenses filter out specific wavelengths of light that create stress on the brain for individuals with Irlen Syndrome. In filtering out these wavelengths of light, they alter the timing at which visual information reaches the brain in a way that allows the brain of someone with Irlen Syndrome to correctly process that information. Color impacts how the brain works, not how the eyes work. Numerous brain imaging studies have shown the normalization of brain function when colored lenses are worn during visually intensive activities, and the most recent fMRI study concluded that the changes in brain function observed directly correspond to improvements in reading (Kim, Seo, Ha, & Kim, 2015).
Certified Irlen practitioners understand the neurology behind the difficulties associated with Irlen Syndrome. They work in conjunction with eyecare professionals who separately address any underlying eyesight issues before tackling the neurological challenges causing the disturbances associated with Irlen Syndrome. The use of color to successfully address the symptoms and challenges related to Irlen Syndrome has been repeatedly documented in literature, and has been confirmed through a variety of brain imaging techniques. We agree that dyslexia has nothing to do with eyesight, but we wish the authors had known a little bit more about why and how color was being used with individuals who suffer from reading problems before claiming that color should not be used to address reading problems.
For more information about Irlen Syndrome, colored overlays, and spectral filters visit www.irlen.com.