In response to Helen saying "you gave the impression of a blanket dismissal of a broad range of scientific studies" I have clearly not made my point - I am dismissing, on the basis of extensive investigation, a broad range of UNscientific studies, based on disproven or unprovable theories.

In response to Helen's assertion that "it is impossible to generalise about dyslexia and dyslexics", you are quite frankly, Helen, incorrect. What they have been able to discover with the use of functional MRI's is neither speculative nor inconsistent. I am talking about recent scientific breakthroughs - cutting edge research, from neuroscientists at the Yale Center for the Study of Learning and Attention, undertaken in the last decade.   

Also, Helen, you say that "even the studies that have been done would not have been able to test all of the different manifestations of dyslexia." I really think it would be helpful to you to read the Shaywitz book, and the research done at Yale - it would do a lot to de-mystify the disorder for you.

Dr. Shaywitz doesn't go into Scotopic Sensitivity Syndrome, but here's an excerpt from one of Ellenpoly's links:

"In 1983 (remember, before we really could see into the brain) a woman named Helen Irlen hypothesized that there might be an underlying neurological problem in encoding and decoding visual information for some people who have trouble learning to read, or for people who have trouble with sustained reading. She futher hypothosized that this problem can be alleviated by adjustments to the appearance of the printed page: that is, special colored lenses in glasses, or colored overlays on the page, and so forth.

They are not such bad hypotheses; its just that the hypothoses, repeatedly, have not been borne out by research.

Since the late 1999s, with the ability to see the brain in action with "functional Magnetic Resonance Imaging" (fMRI) we are learning a lot about dyslexia, and what will and will not work. But parents, or misguided educators, are still recommending "treatments" that have been proven not to work. The internet has made the number of scams, quack diagnoses, and quack treatments even more widely available.

One of these quack diagnoses is "Scotopic Sensitivy Syndrome", also known as Irlen Syndrome.

From an essay by Eugene Helveston, M.D., in Perspectives (IDA)


The perspective afforded by observing the evolution of the concept of scotopic sensitivity syndrome and the treatment with tinted lenses leads to the conclusion that this effort has resulted in classic group behavior. The concept has a strong charismatic personality as originator and sustained leader. The supporting evidence is almost entirely anecdotal. The syndrome is becoming associated with an even more diverse array of maladies, tinted lenses now being offered for relief of problems far removed from reading difficulty. The procedure for determining the specific tint has not been divulged and remains a type of "trade secret." Finally, a financially rewarding franchise activity is at the basis of the Irlen Institute activity.

Another well-researched study concludes:

In a double-blind study of dyslexic children, tinted lens therapy was not shown to improve reading ability subjectively or objectively.39 Studies claiming the efficacy of these lenses have not held up to scientific review. 12.
Citation 39 is Menacker SJ, Breton ME, Breton ML, et al: Do tinted lenses improve the reading performance of dyslexic children? Arch Ophthalmol 111:213-218, 1993.
Citation 12 is Evans BJW, Drasdo N: Tinted lenses and related therapies for leaning disabilities - a review. Ophthal Physiol Opt 11: 206-217, 1991.

The Learning Disabilities Resource community has a good, up-to-date summary on all the Irlen research.

Not only are some findings less meaningful than they first appear, many are questionable on methodological grounds. There continue to be serious methodological concerns with most of the studies claiming support for Irlen lenses. Biased sample selection, small sample size, and lack of proper control procedures are just a few of the more common limitations. Finally, consumers should be aware that many unreported studies show no effects of coloured filters on measures of either reading performance or SSS symptoms.


After a great deal of research, no support could be found for the validity or presence of an actual visual perceptual dysfunction termed "scotopic sensitivity syndrome". Therefore the use of this term is meaningless. Anyone using this term is doing so outside of accepted medical practice.

The symptoms described in "scotopic sensitivity syndrome" can be explained by other, conventional, vision anomalies, that can be treated in more conventional ways if correctly diagnosed."