Despite countless expert statements and empirical studies showing no causal connection between vision disorders and reading disorders, we continue to encounter questions from parents and professionals about the role of vision in dyslexia.
In 2009, the American Academy of Pediatrics along with several other pediatric and ophthalmological organizations released a Joint Statement on Learning Disabilities, Dyslexia, and Vision. In this peer-reviewed paper, the authors unequivocally state, “…vision problems are not the cause of primary dyslexia or learning disabilities…”and “…scientific evidence does not support the efficacy of eye exercises, behavior vision therapy, or special tinted filters or lenses for improving the long-term educational performance in the complex pediatric neurocognitive conditions.” And, in 2014, the American Academy of Ophthalmology along with several other pediatric and ophthalmological organizations re-released this joint statement. The evidence has not changed.
Despite these statements and countless empirical studies showing no causal connection between vision disorders and reading disorders (see Creavin, Lingam, Steer, & Williams, 2015; Handler, 2016; Brown, Haegerstrom-Portnoy, Yingling, Herron, Galin, & Marcus, 1983; Hutzler, Kronbichler, Jacobs, & Wimmer, 2006; Vellutino, Fletcher, Snowling, & Scanlon, 2004), my colleagues and I continue to encounter questions from parents and professionals about the role of vision (and really, vision disorders) in dyslexia. As a result of this perpetuated myth, many of our clients have undergone hundreds of hours (and thousands of dollars) of vision therapy without any positive effects on their reading skills.
At the 2015 International Dyslexia Association (IDA) conference, Dr. Joanne Pierson and I attended a talk presented by a panel of ophthalmologists who began by saying that they weren't sure why they were there, as they knew nothing about dyslexia. During their talk, they proceeded to point out significant limitations in the research that has suggested a causal relationship between vision disorders and reading. (Dr. Pierson wrote Smoke and Mirrors after hearing this talk.) Then, when asked about words moving on a page, blurry words, doubling of words, etc., a pediatric ophthalmologist (and mother of a child with dyslexia) in the audience remarked that these symptoms are manifestations of the effort that is being expended by the reader. That's stuck with me, and I think it's a good way to explain this to parents.
I just returned a few weeks ago from the 2016 IDA conference in Orlando. I had the pleasure of hearing Dr. Guinevere Eden deliver the Norman Geschwind Memorial Lecture. Dr. Eden spoke very eloquently about her work (and others' work) in brain imaging that has really confirmed and extended much of what has been shown over the last 80+ years—beginning with the work of Samuel Orton, then Norman Geschwind, then Albert Galaburda, and so on. Dr. Eden reminded the audience that the visual deficits reported in children with dyslexia are a consequence rather than a cause of dyslexia. She and her colleagues published this finding in 2013 in the journal, Neuron. You can read more about it here.
Dyslexia is a language-based learning disability, and we have known for decades that it requires intensive intervention that targets linguistic weaknesses. Evidence-based explicit and systematic instructional approaches, now referred to as Structured Literacy approaches by the IDA, are effective in teaching children (and adults) with dyslexia how to read and spell. The intervention road for dyslexics is long and hard, and there are no quick or easy fixes. As alluring as it may be, the eyes still don’t have it.
By Lauren A. Katz, Ph.D., CCC-SLP
Partner, Literacy, Language, and Learning Institute (3LI)