I frequently overhear comments made by professionals which suggest on their part an incomprehension about Irlen Syndrome. Yet these well-meaning individuals work in fields that are very close to mine: learning, perceptual difficulties and optimising brain functioning. Some of these issues I wish to address in this instalment.
This simple statement suggests a basic misunderstanding of Irlen’s Syndrome that I wish to discuss. This well-meaning professional had the best intentions, but did not take into account the fact that distortions may not always manifest themselves after only a few sentences. A study by Tyrrell, R., Holland, K., Dennis, D. and Wilkins A. (1995) (i) suggests, in fact, that on the average there needs to be about 10 minutes of demanding visual activity such as reading before the typical symptoms of Irlen syndrome occur: moving letters, narrowing of the visual span [ii], waving of the lines of text, distortion of the background such as the apparition of colors, gray or bright zones, auras, etc. These distortions alone will make reading less efficient, will hamper comprehension and lead to visual fatigue, which in turn will have an effect on attention.
The rate of reading is not the only aspect that a rigorous professional should consider when assessing the value of color filters. There are other elements such as fatigue, distractibility, discomfort, and the numbers of errors and self-corrections. For the sake of objectivity, one should consider the degree of fatigue and discomfort after a visually demanding task of at least 15 minutes, then only then question the student about his experiences comparing a white page and a “protected” page using a Irlen® color filter. Consideration should be given to the subtle facial signs of visual stress (squinting, etc.)
Another expression of scientific rigor would be to observe and compare the length of time the student will remain attentive, during a reading period, with and without filters. Will he require more rest periods, in one situation compared to the other? Can he or she remain on task longer? Is he or she better at picking up information from the page? Will he or she show more or less fatigue at the end of the school day? Finally, is he or she better at self-correcting small mistakes? Any improvements in these areas suggests that the brain has more resources available to deal with tasks that are metacognitive in nature.
Jacques Guimond, Irlen Diagnostician
[i] Tyrrell, R., Holland, K., Dennis, D. et Wilkins, A. (1995) - Coloured Overlays, Visual Discomfort, Visual Search and Classroom Reading. Journal of Research in Reading, 18(1), pp 10-23
[ii] Do not confuse with peripheral vision. Visual span is the area of the field of vision where the text is sharp enough to be read without the need for the eye to move on the page.
[iii] Lewine, J.D. (1999). - Changes in visual evoked magnetic field for people with SS/S.
Fourth Biannual Australasian Irlen Conference. Newcastle, Australia, May 20-22
[iv] Wilkins, Huang et Cao, (2007) Prevention of Visual Stress and Migraine With Precision Spectral Filters – Research Overview, Drug Development and Research 68:469–475 (2007)