MedicalResearch.com Interview with:
Aparna Raghuram, OD, PhD
Optometrist, Department of Ophthalmology
Instructor, Harvard Medical School
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Developmental dyslexia is a specific learning disability of neurobiological origin whose core cognitive deficit is widely believed to involve language (phonological) processing. Although reading is also a visual task, the potential role of vision has been controversial, and experts have historically dismissed claims that visual processing might contribute meaningfully to the deficits seen in developmental dyslexia.
Nevertheless, behavioral optometrists have for decades offered vision therapy on the premise that correcting peripheral visual deficits will facilitate reading. Yet there is a surprising dearth of controlled studies documenting that such deficits are more common in children with developmental dyslexia, much less whether treating them could improve reading.
In the present study, we simply assessed the prevalence and nature of visual deficits in 29 school aged children with developmental dyslexia compared to 33 typically developing readers. We found that deficits in accommodation 6 times more frequent in the children with developmental dyslexia and deficits in ocular motor tracking were 4 times more frequent.
In all, more than three-quarters of the children with developmental dyslexia had a deficit in one or more domain of visual function domain compared to only one third of the typically reading group.