45th Annual Conference of the International Military Testing Association
Pensacola, Florida
November 3-6, 2003
PERCEPTUAL DYSLEXIA:
> ITS EFFECT ON THE MILITARY CADRE AND BENEFITS OF TREATMENT
> Susann L. Krouse
> Naval Education and Training
> Professional Development and Technology Center Pensacola, FL, USA
> James H. Irvine
> Naval Air Warfare Center, Weapons Division
> China Lake, CA, USA
>
> Perceptual dyslexia-also known as Irlen Syndrome, Scotopic Sensitivity
> Syndrome, SSS, scotopic sensitivity/Irlen syndrome, and, in the United
> Kingdom, Meares-Irlen Syndrome-is a perceptual disorder that affects an
> estimated 46-50 percent of those with learning disabilities or reading
> problems; 33 percent of those with dyslexia, attention deficit
> (hyperactivity) disorder, and other behavior problems; and approximately
> 12-14 percent of the general population (Irlen, 1999). It is not a
> dysfunction of the physical process of sight. People with perceptual
> dyslexia can have 20/20 vision or they may wear corrective lenses.
> Perceptual dyslexia is a problem with how one’s nervous system encodes and
> decodes visual information and transmits it to the visual cortex of the
> brain (Warkentin & Morren, 1990).
>
> SYMPTOMS OF PERCEPTUAL DYSLEXIA
>
> People who are affected with perceptual dyslexia have problems accommodating
> specific wave-lengths of light, and each person’s troublesome frequency is
> unique. Factors such as bright light, fluorescent light, high-gloss paper,
> and black-and-white contrast can aggravate the disorder. The victim’s scope
> of focus may be restricted so that he or she may only see very small bits of
> a line of text instead of the entire line. The text that the person sees
> might blur, swirl, move, pulsate, vibrate, or even disappear. The white page
> is too bright; or it may flicker or flash; or colors may appear. SSS victims
> rarely report these symptoms to others because they think that everyone
> experiences the same problems (Irlen, 1991). Those with perceptual dyslexia
> often avoid reading at all costs, and, as a result, they may be affected
> physically, academically, and psychologically (Irlen, 1991).
>
> From a physical standpoint, because of the text distortions suffered,
> reading becomes extremely difficult, often physically painful. Without
> intervention, victims of Irlen Syndrome exhibit symptoms such as sensitivity
> to light, headaches, nausea, eyestrain, sleepiness while reading, attention
> deficit, and distortions of text (Irlen, 1991).
>
> Academically, everything derives from reading, and victims of Irlen Syndrome
> invariably find it difficult to read. They may skip words or reverse or
> change letter order-seeing the word “saw” as “was,” for instance. They may
> have poor penmanship, a result of difficulty with spatial orientation: they
> misjudge how much space to leave between a pair of letters or words. Because
> they frequently can’t envision an entire word, they find it difficult to
> spell or work with large numbers (Irlen, 1991).
>
> Psychologically, the victim of perceptual dyslexia is prone to exhibit
> problems with behavior, motivation, and self-esteem. Those with SSS
> frequently exhibit symptoms of attention deficit disorder, acting out, and
> behavior problems (Irlen, 1991). They are often poorly motivated to succeed.
> Almost invariably they tried early on, when they were young. But with few
> successes and many “failures,” their attitude became “why bother?” Their
> selfesteem is low because, while everyone around them is reading and
> learning, they cannot-no matter what they do or how hard they work, they
> just can’t seem to “get it.”
>
> Identification of SSS
>
> Helen Irlen, a literacy instructor in California, first identified this
> perceptual dyslexia in the early 1980s and labeled it “scotopic sensitivity
> syndrome.” Irlen had received a grant from California State University,
> Long Beach, in 1980, to set up a literacy program for adults. She chose to
> work with adults because adults can communicate better than children and are
> more accurate “reporters” of what they experience; they are less intimidated
> by authority than children and are less likely to he swayed without some
> evidence; and adults are more motivated to succeed. They have reached a
> point in their lives where they recognize the importance of learning in
> general and reading in particular.
>
> After three years of in-depth research, Irlen discovered that many problems
> appeared after readers had been actively reading for a relatively short
> period of time (usually about 10 minutes or more). Those who had trouble
> reported that distortions began to appear on the page, and those distortions
> prevented them from comprehending the words. All of their energy was going
> into perceiving the words, holding them on the page, or even just finding
> them! As a result, many stopped reading. It was just too difficult for them.
> As Irlen explained in her speech at the dyslexia Higher Education
> Conference, October 31-November 2, 1994, at Plymouth University, England,
> once she began asking the more definitive question, “WHAT do you see?”
> instead of “DO you see?” the answers made it apparent to her that these poor
> readers were victims of a unique syndrome that was not being adequately
> addressed by the professional educational community. (Dyslexia in higher
> education: strategies and the value of asking).
>
> Serendipitous Discovery
>
> One day, one of Irlen’s students discovered that when she placed a red
> overlay-left over from previous eye-dominance exercises-on the page she was
> reading, the sensation of movement that she had always experienced stopped!
> For the first time, she could actually read without having the words
> constantly sway back and forth! (Irlen, 1991) The red didn’t work for
> everybody, however. It made no difference to the rest of the students.
>
> So, Irlen tried other colors and found that the vast majority of those who
> tried the colored overlays were helped. Each person who was helped responded
> to one specific color. Once that particular color was determined and used,
> the individual was able to read better and longer and reported that the
> distortions previously experienced disappeared immediately. Irlen didn’t
> know at that time why the overlays worked, just that they did.
>
> RESEARCHING THE CAUSE
>
> With the advent of magnetic resonance imaging, we’ve been able to determine
> that the brains of all dyslexics-including perceptual dyslexics-work
> differently than those of non-dyslexics. (Lewine, et al., in press)
> Dyslexics use a different part of the brain than nondyslexics when they
> read, and they use a larger portion of their brain when they read or perform
> visual tasks.
>
> Receptor Field Theory
>
> In the 1980s, visual physiologists developed the receptor field theory of
> color vision. This theory hypothesizes that the cones of the eyes are
> organized into eight sets of concentric, counterbalancing fields. Cones, of
> course, help us distinguish things clearly and distinctly. Because they
> contain photo pigments that are sensitive to red, green, and blue light
> wavelengths, we are able to see color.(Irvine, 2001)
>
> Each type of field is determined by the field’s color region arrangement and
> the balance of the output of each field’s energy or signal. The output
> should be equal-that is, neither positive nor negative-as it passes through
> the optic nerve to enter the brain’s visual processing center. (Irvine,
> 2001)
>
> If the receptor fields are summed to a unity as they enter the brain’s
> processing center, and each single receptor field is equal to the others (so
> that none is governing or dominant), there will be no perceptual distortion,
> and the image formed will be accurate. On the other hand, if any of the
> receptor fields does not sum to a unity or is, in fact, dominant under a set
> of spectral input conditions, the visual control system will change, and the
> image formed will overlap, swirl, jump about-generally be distorted.
> (Irvine, 2001)
>
> The Pathways to the Visual Cortex
>
> Over the years since Irlen’s discovery, numerous studies of this
> visuo-perceptual disorder have been conducted, and the general consensus is
> that scotopic sensitivity syndrome affects the way the visual pathways carry
> messages from the eye to the brain.
>
> There are two pathways to the visual cortex:
>
> 1. the magnocellular, which does fast processing of information for
> perceiving position, motion, shape, and low contrast; and
> 2. the parvocellular, which carries out slower processes for perceiving
> still images, color, detail, and high contrast.
>
> It is theorized that when the receptor fields do not sum to unity, the
> pathways are affected, causing the magnocellular impulses to be slowed, so
> only partial perception occurs. This results in words that blur, fuse, or
> seem to jump off the page (Newman, 1998). Individualized colored filters
> seem to return the balance between the two processing systems, preventing
> this overlapping (Robinson, 1994). The colored overlays and filters cut down
> or eliminate the perceptual problem by screening out the wavelengths of
> light troublesome to the individual (Sims, 1999). Studies of both the long-
> and short-term efficacy of the transparencies and filters have shown that
> they do, indeed, provide benefits to the individual afflicted with SSS
> (Whiting, Robinson, & Parrott, 1990; Robinson & Conway, 1990).
>
> THREE STUDIES
>
> Although there have been numerous studies into perceptual dyslexia since its
> recognition in 1983, we will look at just three in this paper: Irvine,
> Lewine, and Wilkins.
>
> Irvine’s Experiment for the Navy
>
> The Navy wanted to see if the visual performance of those afflicted with
> perceptual dyslexia changed as the energy spectrum presented to them
> changed. Therefore, in 1995, James Irvine conducted an experiment at China
> Lake, California, that showed that for certain perceptual dyslexics the
> receptor fields do NOT sum to unity, so the image sent to the brain is not
> crisp and clear. When this happens, the subject’s visual control system
> alters radically, so the subject does not see the image properly. (Irvine &
> Irvine, 1997)
>
> Lewine’s Study
>
> In the late 1990s, Dr. Jeffrey Lewine, a neuroscientist then at the
> University of Utah Center for Advanced Medical Technologies, discovered that
> modifying the light frequency spectrum that went to a perceptual dyslexic’s
> vision system could make the brain alter and revert to a more normal brain
> pattern. He also noted that he could actually cause five to six percent of
> the “normal” population to develop dyslexic-type dysfunction when they were
> exposed to “abnormal” light frequency environments. (Lewine, et al., in
> press) This means that some ordinarily non-dyslexic personnel can develop
> gross inefficiency, degraded performance, and/or become dysfunctional and
> unable to perform normally under certain lighting conditions such as red
> battle lighting, blue precision operating bays, or in foggy or hazy
> conditions.
>
> Wilkins’ Studies
>
> Professor Arnold Wilkins, while a research scientist at the Medical Research
> Council Applied Psychology Unit of Cambridge University in the United
> Kingdom, studied the neuropsychology of vision, reading and color,
> photosensitive epilepsy, and attention, conducting double-blind experiments
> to validate the existence and potential treatment of perceptual dyslexia. He
> did this using four different groups of readers, mostly children,
> randomizing the presentation order of the overlays, and further randomizing
> the use of the appropriate overlays versus placebo overlays. (Wilkins, 2003)
>
> Wilkins’ studies determined that, when given the choice, about half the
> readers would choose clear overlays, and the other half would choose the
> colored overlays. Given that only approximately 15 percent of the population
> is afflicted with perceptual dyslexia, we can assume from Wilkins’
> experiments that, in addition to these people being helped by the colored
> overlays or filters, some of those not-so-afflicted can also benefit from
> color!
>
>
> TESTING AND TREATMENT
>
> Generally speaking, before we can treat perceptual dyslexics, we have to
> identify them.
>
> Types of Screening
>
> There are generally three types of screening, two of which are based on the
> Irlen Method:
>
> 1. In the field or at the recruiting site, a simple, 10- to 15-question
> inquiry of the subject, and trial-and error determination of the appropriate
> colored overlay.
> 2. At the Recruit Training Center or a major command, an in-depth inquiry
> consisting of questions concerning the subject’s symptoms and related
> history.
>
> The third test, the Wilkins Rate of Reading Test, is also easy to administer
> and consists of four easy one minute tests. The entire process should not
> take more than about a half hour.
>
> Resources Required
>
> There are many ways to improve the situation for perceptual dyslexics
> without having to spend a penny. Such simple and cost-free actions as
> dimming the lights in a room, using natural instead of fluorescent lighting,
> allowing students to use colored paper and to wear caps or visors indoors,
> and avoiding the use of white boards will all help. (Irlen, undated;
> Wilkins, 2003)
>
> But to alleviate the problem requires intervention in the form screening
> and, ultimately, selection of appropriate colored overlays or filters. The
> outlay required to implement such a program would be minimal. Only basic
> instructions would be required at the recruiting sites, enough training for
> the recruiter to be able to administer the simple Irlen Type-1 test or the
> Wilkins Rate of Reading test and to assist the applicant in choosing the
> appropriate overlay. At the Recruit Training Center, it is anticipated that
> one or two Educational Specialists who have backgrounds in education and
> have been trained in the Irlen Method will be required to administer the
> screening and perform the diagnostic analysis.
>
> Supplies of overlays or transparencies for recruiting sites and the Recruit
> Training Center will also be necessary. Overlays from Irlen Institute cost
> approximately $1.25 each, although less expensive transparencies are
> available from other commercial sources. (It must be remembered, however,
> that Irlen overlays are specifically designed and developed for the purpose
> of alleviating SSS.) Tinting of lenses (whether corrective or not) adds
> about $50 to $100 per pair at this point in time. Under contract, however,
> the price will certainly drop to a more nominal figure (Irvine, 1997).
>
> MILITARY APPLICATION
>
> And what will we get back for this investment? The individual service
> members will benefit, of course, with improved reading speed and
> comprehension. Because they will experience less visual fatigue, their
> attention spans will increase. As they begin to understand and realize that
> they can do what they thought they couldn’t do, their self confidence will
> improve, as will their attitude to training and the job itself. Just knowing
> that there is a solution available will often be enough to change an
> attitude and strengthen a resolve to succeed.
>
> The military services will also reap the rewards of this program because, in
> addition to increasing the qualified pool of applicants for enlistment, the
> young people affected will be able to train more efficiently. Remediation,
> basic, and ongoing training will be more effective and, as a result, more
> efficient. With more effective training, the service member will be more
> knowledgeable and efficient in the field. It can further be anticipated that
> there will be fewer behavioral problems-both during and after
> training-primarily due to the change in attitude that has been shown to
> occur following screening and diagnosis for SSS.
>
> All in all, we believe that a higher-quality service member will be
> delivered to the field or fleet, both academically and attitudinally.
>
> References
>
> Borlik, SSG A. (1999). Services grapple with recruiting challenges. American
> Forces Information Service.
>
> Irlen, H. (1991). Reading by the colors. Garden City Park, NY: Avery
> Publishing Company.
>
> Irlen, H. (1999). Irlen Syndrome/Isotopic Sensitivity: Most Frequently Asked
> Questions. Retrieved September 20, 1999, from the World Wide Web:
> http://Irlen.com/sss.faq.htm
>
> Irlen, H. (undated) Tips and Research from Helen Irlen. ACNOnline:
> Association for Comprehensive Neuropathy. Retrieved October 31, 2003, from
> the World Wide Web:
> http://www.latitudes.org/articles/irlen_tips_research.htm
>
> Irvine, J. H. (1997). Dyslexic effect on the Navy training environment and
> operational efficiency: A prognosis for improvement. (Briefing.)
>
> Irvine, J. H. (2001). The cause of Arleen syndrome. (Briefing.)
>
> Irvine, J. H., & Irvine, E. W. (1997). Isotopic sensitivity syndrome in a
> single individual (a case study). Naval Air Warfare Center, Weapons
> Division, China Lake, California, April.
>
> Lewine, J. D., Davis, J. T., Provencal, S., Edgar, J. C., & Orrison, W. W.
> (in press). A magnetoencephalographic investigation of visual information
> processing in Irlen’s scotopic sensitivity syndrome. Perception.
>
> Newman, R. M. (1998). Technology for dyslexia: Federal education &
> disability law compliance.
>
> Robinson, G. L., & Conway, R. N. (1990). Irlen filters and reading
> strategies: The effect of coloured filters on reading achievement, specific
> reading strategies and perception of ability. Retrieved on August 19, 1999,
> from the World Wide Web: http://www.edfac.usyd.au/centres/children/Greg.html
>
>
> Robinson, G. L. (1994). Coloured lenses and reading: A review of research
> into reading achievement, reading strategies and causal mechanisms.
> Australasian Journal of Special Education, 18(1), 3-14, citing M. C.
> Williams, K. Lecluyse, & A. Rock-
>
> Facheux (1992), Effective interventions for reading disability, Journal of
> the American Optometric Association, 63(6), 411-417.
>
> Sims, P. (1999). Awakening brilliance. Retrieved August 19, 1999, from the
> World Wide Web: http://www.onlineschoolyard.com
>
> Warkentin, M., & Morren, R. (1990). A perceptual learning difference. Notes
> on Literacy, 1990-1994 (vol. 64, Oct. 1990).
>
> Whiting, P. R., Robinson, G. L., & Parrott, C. F. (1990). Irlen coloured
> filters for reading: a six-year follow-up. Retrieved on August 19, 1999,
> from the World Wide Web:
> http://www.edfac.usyd.edu.au/centres/childrens/SixYr.html
>
> Wilkins, A. J. (2003). Reading through colour. West Sussex: John Wiley &
> Sons Ltd.
>
> ________________________________________________________________
