Back to table of contents Previous article Next article LettersFull AccessThe Effect of Visual and Cerebellar Exercises on DyslexiaMona Delavarian, M.D., G. Ali Afrooz, M.D., and Shahriar Gharibzadeh, M.D., Ph.D.Mona DelavarianSearch for more papers by this author, M.D., G. Ali AfroozSearch for more papers by this author, M.D., and Shahriar GharibzadehSearch for more papers by this author, M.D., Ph.D.Published Online:1 Jan 2013https://doi.org/10.1176/appi.neuropsych.12020035AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail To the Editor: Reading disorder, or dyslexia, affects at least 5% of school-age children.1 This disorder has a genetic basis. The learning difficulties in these persons are unexpected according to age and cognitive or academic abilities.2The exact etiology of dyslexia is unknown. Some studies have declared that the visual magnocellular system of the lateral geniculate nucleus is immature in dyslexics.3,4 This immaturity leads to a reduction in their motion sensitivity, which causes deficiency in identifying the visual order of letters and the visual form of the words.3It should be noticed that the cerebellums of dyslexics have some anatomical, metabolic, and activation differences in some brain-imaging studies.2 There is a powerful hypothesis about this dysfunction, which claims that dysfunction of the cerebellum in dyslexics leads to motor and cognitive problems associated with reading.2 Impaired balance and time perception in studies on people with learning disability confirm the differences in cerebellum functions also.2Based on the abovementioned evidences, one of the most important parts impaired in dyslexia is the visual magnocellular system. We hypothesized that visual stimulation in a dark room will excite the visual magnocellular system, and in this way the cerebellum will be affected too, because the cerebellum receives many inputs from various magnocellular systems.3 It is also believed that general magnocellular defects affect the cerebellum.2 By stimulating the dorsal tract of visual magnocellular system (this tract seems to gradually develop through neuro-plasticity) and by visual stimulation, visual attention and eye movements following the letters will be improved because the visual magnocellular system plays the main part in controlling these two items. It is suggested that the stimulus presents as searching and tracking a radiant object to improve visual tracking and visual attention. Adding cerebellum rehabilitation leads to 1) increasing attention;5 and 2) improving equilibrium,6 which are both impaired in individuals with learning disorder, especially in dyslexia. It is recommended that the cerebellum and vision stimulations be done simultaneously through sensory-integration exercises so that it will be more effective on functional improvement. Surely, for confirming this hypothesis, larger clinical trials are needed.Faculty of Psychology and Education University of Tehran, Iran, TehranBiomedical Engineering Faculty Amirkabir University of Technology Iran, TehranReferences1 Sadock BJ, Sadock VA: Kaplan & Sadock's Synopsis of Psychiatry: Behavioral Sciences/Clinical Psychiatry, 10th Edition. Baltimore, MD, Lippincott Williams & Wilkins, 2007Google Scholar2 Sadock BJ, Sadock VA: Kaplan & Sadock’s Comprehensive Textbook of Psychiatry, 8th Edition, Vol II. Baltimore, MD, Lippincott Williams & Wilkins, 2005Google Scholar3 John Stein: The magnocellular theory of developmental dyslexia. Dyslexia 2001; 7:12–36Crossref, Medline, Google Scholar4 Ungerleider LG, Mishkin M: Two Cortical Visual Systems. Edited by Ingle DJ, Goodale, MA. Cambridge, MA, MIT Press.1982Google Scholar5 Mansfield RJ (ed): The Analysis of Visual Behavior. Cambridge, MA, MIT Press, pp 549–586Google Scholar6 Delavarian M, Gharibzadeh S: The role of cerebellar rehabilitation in improvement of ADHD imbalance. J Neuropsychiatry Clin Neurosci 2011; 23:E34Link, Google Scholar FiguresReferencesCited byDetailsCited ByEffects of oculomotor rehabilitation on the cognitive performance of dyslexic children with concurrent eye movement abnormalities21 July 2020 | Early Child Development and Care, Vol. 192, No. 4 Volume 25Issue 1 Winter 2013Pages E31-E31 Metrics PDF download History Published online 1 January 2013 Published in print 1 January 2013