Effect of Induced Visual Fatigue on Sensory Ocular Dominance and the Effect of Colored Filters on the Levels of Visual Fatigue in Dyslexic Adults with MIS
International Journal of Ophthalmology & Visual Science
Volume 5, Issue 1, March 2020, Pages: 1-10
Received: Dec. 4, 2019;
Accepted: Dec. 18, 2019;
Published: Jan. 4, 2020
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Mana Alafri Alanazi, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
The aim of the current research was to investigate the effect of visual fatigue induced with different clinical test stimuli on the sensory ocular dominance in dyslexic adults with Mearles-Irlen syndrome (MIS) and examine the role of colored filters. Nine female participants with dyslexia plus MIS aged between 18 and 36 years were recruited. Sensory ocular dominance and binocular vision functions were measured before and after induction of visual fatigue was induced. Measurements were conducted with participants wearing their habitual colored filters and without the filters and in two different sessions. Constant and continuous (static) test stimuli were used to create binocular rivalry. To induce visual fatigue, participants were asked to read, copy, and search for thirty minutes; the participants performed each tasks for ten minutes, while wearing their habitual near spectacle lens. No breaks were allowed between tasks. The calculated visual discomfort score (VDCS) for each test condition was analyzed. In sessions one and two respectively, VDCS was increased from 0.67 ± 1.00 to 1.44 ± 0.53 (p = 0.07) and 0.22 ± 0.44 to 1.56 ± 0.73 (p = 0.001), in adults with dyslexia and MIS after assessment of binocular vision function. Similarly, the VDCS was significantly increased to 2.56 ± 0.73 (p = 0.002) in session one and 2.11 ± 0.93 (p = 0.001) in session two, after visual fatigue was induced in these participants. There were no differences between both eyes’ sensory ocular dominance in dyslexic adults with MIS irrespective of the test stimuli used to induce the binocular rivalry. Induction of visual fatigue was followed by disruptions in the sensory ocular dominance that persisted with participants wearing their habitual colored overlays during the fatigue duration. This finding was also not influenced by the test slides used in these participants. Optometric investigations such as binocular vision testing, performed in dyslexic adults with MIS using certain stimuli could induce visual discomfort, but the discomfort induced by stressful visual testing was significantly greater. Moreover, the use of certain test stimuli was shown to disrupt the sensory ocular dominance of this group of participants suggesting that researchers should consider using the appropriate stimuli when examining patients with dyslexia and/or MIS and those experiencing reading difficulties.
Mana Alafri Alanazi,
Effect of Induced Visual Fatigue on Sensory Ocular Dominance and the Effect of Colored Filters on the Levels of Visual Fatigue in Dyslexic Adults with MIS, International Journal of Ophthalmology & Visual Science.
Vol. 5, No. 1,
2020, pp. 1-10.
Lyon GR, Shaywitz SE, Shaywitz BAJAod. A definition of dyslexia. JSTOR 2003; 53: 1–14.
Taub MB, Shallo-Hoffmann J, Steinman S, Steinman B. The effect of colored overlays on reading eye movements in adults. J. Behav. Optom. 2009; 20: 143–149.
Wilkins AJ, Evans BJ. Visual stress, its treatment with spectral filters, and its relationship to visually induced motion sickness. Appl. Ergon. 2010; 41: 509–515.
Evans BJW, Wilkins AJ, Brown J, Busby A, Wingfield A, Jeanes R et al. A preliminary investigation into the aetiology of Meares-Irlen syndrome. Ophthalmic Physiol. Opt. 1996; 16: 286–296.
Evans BJW. The need for optometric investigation in suspected Meares–Irlen syndrome or visual stress. Ophthalmic Physiol. Opt. 2005; 25: 363–370.
Kriss I, Evans BJW. The relationship between dyslexia and Meares-Irlen syndrome. J. Res. Read. 2005; 28: 350–364.
Wilkins A, Allen PM, Monger LJ, Gilchrist JM. Visual stress and dyslexia for the practicing optometrist. Optom. Practice 2016; 17: 103–112.
Chouinard BD, Zhou CI, Hrybouski S, Kim ES, Cummine J. A functional neuroimaging case study of Meares–Irlen syndrome/visual stress (MISViS). Brain Topogr. 2012; 25: 293–307.
Evans BJW. Dyslexia and Vision: Wiley; Whurr Publishers Ltd, Londion, UK, 2001.
Irlen H. Scotopic sensitivity/Irlen syndrome: hypothesis and explanation of the syndrome. J. Behav. Optom. 1994; 5: 65–66.
Stein JF, Fowler S. Diagnosis of dyslexia by means of a new indicator of eye dominance. British J. Ophthalmol. 1982; 66: 332–336.
Wilkins A, Huang J, Cao Y. Visual stress theory and its application to reading and reading tests. J. Res. Read. 2004; 27: 152–162.
Huang J, Cooper TG, Satana B, Kaufman DI, Cao Y. Visual distortion provoked by a stimulus in migraine associated with hyperneuronal activity. Headache 2003; 43: 664–671.
Chang M, Kim S-H, Kim J-Y, Cho YA. Specific visual symptoms and signs of Meares-Irlen syndrome in Korean. Korean J. Ophthalmol. 2014; 28: 159–163.
Wilkins AJ, Evans BJ, Brown JA, Busby AE, Wingfield AE, Jeanes RJ et al. Double-masked placebo-controlled trial of precision spectral filters in children who use coloured overlays. Ophthalmic Physiol. Opt. 1994; 14: 365–370.
Walls GL. A theory of ocular dominance. AMA Arch. Ophthalmol. 1951; 45: 387–412.
Porac C, Coren S. Lateral Preferences and Human Behavior: Springer-Verlag: New York, USA,1981.
Handa T, Mukuno K, Uozato H, Niida T, Shoji N, Shimizu K. Effects of dominant and nondominant eyes in binocular rivalry. Optom. Vis. Sci. 2004; 81: 377–383.
Ooi TL, He ZJ. Sensory eye dominance. Optometry 2001; 72: 168–178.
Orton ST. Word-blindness in school children. Archiv. Neurol. Psychiatry 1925; 14: 581–615.
Evans BJ, Drasdo N, Richards IL. Investigation of accommodative and binocular function in dyslexia. Ophthalmic Physiol. Opt. 1994; 14: 5–19.
Mendola JD, Conner IP. Eye dominance predicts fMRI signals in human retinotopic cortex. Neurosci. Lett. 2007; 414: 30–34.
Alanazi MA. Studies of Visual Functions and the Effect of Visual Fatigue in Adults with Dyslexia: PhD Thesis, Cardiff University: UK, 2010.
Wiesenfelder H, Blake R. The neural site of binocular rivalry relative to the analysis of motion in the human visual system. J. Neurosci. 1990; 10: 3880–3888.
O'Shea RP, Blake R, Wolfe JM. Binocular rivalry and fusion under scotopic luminances. Perception 1994; 23: 771–784.
Freeman AW, Nguyen VA. Controlling binocular rivalry. Vis. Res. 2001; 41: 2943–2950.
Bonneh Y, Sagi D, Karni A. A transition between eye and object rivalry determined by stimulus coherence. Vis. Res. 2001; 41: 981–989.
Bouldoukian J, Wilkins AJ, Evans BJ. Randomised controlled trial of the effect of coloured overlays on the rate of reading of people with specific learning difficulties. Ophthalmic & Physiol. Opt. 2002; 22: 55–60.
Aasved H. Ophthalmological status of school children with dyslexia. Eye 1987; 1: 61–68.
Uccula A, Enna M, Mulatti C. Colors, colored overlays, and reading skills. Front. Psychol. 2014; 5: 833.
Imaizumi S, Hibino H, Koyama S. Effect of colored overlays on reading comfort in people with and without Meares-Irlen syndrome. Int. J. Affect. Eng. 2016; 15: 21–28.
Alanazi MA, Alanazi SA, Osuagwu UL. Evaluation of visual stress symptoms in age-matched dyslexic, Meares-Irlen syndrome and normal adults. Int. J. Ophthalmol. 2016; 9: 617–624.
Carlson TA, He S. Visible binocular beats from invisible monocular stimuli during bivocular rivalry. Curr. Biol. 2000; 10: 1055–1058.
Facoetti A, Lorusso ML, Paganoni P, Cattaneo C, Galli R, Mascetti GG. The time course of attentional focusing in dyslexia and normally reading children. Brain and Cogn. 2003; 53: 181–184.
Skottun BC, Skoyles JR. Attention, reading and dyslexia. Clin. Exp. Optom. 2006; 89: 241–245.
Boden C, Giaschi D. M-Stream deficits and reading related visual processes in developmental dyslexia. Psychol. Bull. 2007; 133: 346–366.
Wilkins AJ. Visual Stress. Oxford Psychology Series, Oxford University Press: New York, NY, US, 1995.