Pacific University CommonKnowledge
College of Optometry Theses, Dissertations and Capstone Projects
5-1988
An overview of dyslexia from the perspective of an optometry student
Timothy Mark Westgate Pacific University
Recommended Citation Westgate, Timothy Mark, "An overview of dyslexia from the perspective of an optometry student" (1988). College of Optometry. 864. https://commons.pacificu.edu/opt/864
This Thesis is brought to you for free and open access by the Theses, Dissertations and Capstone Projects at CommonKnowledge. It has been accepted for inclusion in College of Optometry by an authorized administrator of CommonKnowledge. For more information, please contact [email protected]. An overview of dyslexia from the perspective of an optometry student
Abstract Dyslexia has been a topic of much debate as to causes and possible cures. This paper explores the various areas of dyslexia and learning disability to educate the reader as to the controversy involved among professions. There exists strong opposition toward Optometric intervention in this area however, there are arguments for specific treatment approaches addressing visual problems that can coexist with dyslexia. An overview of present theories will be presented along with general recommendations the Optometrist can follow in managing the dyslexic.
Degree Type Thesis
Degree Name Master of Science in Vision Science
Committee Chair Hannu Laukkanen
Subject Categories Optometry
This thesis is available at CommonKnowledge: https://commons.pacificu.edu/opt/864 Copyright and terms of use
If you have downloaded this document directly from the web or from CommonKnowledge, see the “Rights” section on the previous page for the terms of use.
If you have received this document through an interlibrary loan/document delivery service, the following terms of use apply:
Copyright in this work is held by the author(s). You may download or print any portion of this document for personal use only, or for any use that is allowed by fair use (Title 17, §107 U.S.C.). Except for personal or fair use, you or your borrowing library may not reproduce, remix, republish, post, transmit, or distribute this document, or any portion thereof, without the permission of the copyright owner. [Note: If this document is licensed under a Creative Commons license (see “Rights” on the previous page) which allows broader usage rights, your use is governed by the terms of that license.]
Inquiries regarding further use of these materials should be addressed to: CommonKnowledge Rights, Pacific University Library, 2043 College Way, Forest Grove, OR 97116, (503) 352-7209. Email inquiries may be directed to:[email protected] An Overview of Dyslexia from the Pe spective of an Optometry Student
by: • Timothy . ark ~' stgate
A Thesis Submitt ed t o the Facu ty of the College of Optometry Pacific University Forest Grove:~ Oregon For the Degree of Doctor of Optometry May 1988
Adviser
Dr. Hannu Laukkanen, O.D.
PACI FIC ~NIVERSITY LIBRARY FORESJ GROVE, OREGON Abstract
Dyslexia has been a toptc of much debate as to causes and possible cures. This paper explores the various areas of dyslexia and learning disability to educate the reader as to the controversy involved among professions. There exists strong opposition toward
Opton1etr1c intervention in this area however, there are arguments for specific treatment approaches addressing visual problerns that can coexist with dyslexia. An overview of present theories will be presented along with general recommendations the Optometrist can follow in rnanaging the dyslexic. ~ '
Introduction
As an Opton1etry student about to leave the formal education arena and join the ranks of practicing practitioners, there are n1any questions yet to be answered. The rnain question to be addressed in this paper is, "How is the optometrist as a. primary health care practitioner going to n1anage the "dyslexic" patient?"
The parents of these kinds of patients, including learning disabled and those \Vith other reading problems, seek out the opinion of the
Opton1etrist many tin1es as the first approach in addressing their child's problen1. \Ve need to be knowledgeable in the area of dyslexia and other learning disabilities in order to proper Iy diagnose and/or manage the specific visual problems. In addition to the visual problen1s, we n1ust also be able to identify other problems that can coexist with the - learning disability. Accurate identification .of these other related problems facilitates effective referral to the appropriate professionals.
The intent of this paper is to explore the current literature on dyslexia for definitions, diagnosis, and management options.
Analysis of this information will help to build a "philosophy" as to how tl1e Optometrist can approach cases with learning disabilities and dyslexia.
-1- l '
The Optometrist is faced with this rnanagement decision many times. It is the goal of this literature review to make this management decision an easy and efficient process.
One does not 11ave to look very far for an array of definitions of dyslexia. Crithley(1970) gives two definitions of dyslexia derived from a meeting of an international body of experts called The
Research Group on Developrnental Dyslexia of the World Federation of Neurology. The definitions as published read ... 6
"Specific Developn1ental Dyslexia- a disorder manifested by the
in learning to read despite conventional instruction,
adequate intelligence, and sociocultural opportunity. It is
dependent upon fundan1ental cognitive disabilities which are
frequently of constitutional origin."
"Dyslexia- a disorder in children who, despite conventional
classroon1 experience, fail to attain the language skills of
reading, writing, and spelling commensurate with their
intellectual abilities." 6
Thon1pson (1984) cites several researchers who have subtyped dyslexics into specific groupings according to deficiencies
-2- characteristic or each group.3o Boder describes three sub groups and
Griffin has added four more groups to these to total seven groups as described in the Dyslexia Deterrrlination Test (DDT) .(5, 11, 30)
Along with each and subgroup of dyslexia comes an assorted array of test batteries for the diagnosis. The Optometrist needs to decide which test batteries are appr<.-priate for his /her particular practice as well as what approach will be taken after diagnosis.
Diagnosis
Diagnosis of the dyslexic is con1plicated and as diverse as the
1r1any definitions. Dobbs (1976) describes an educational test battery including including ten individual tests to give quantitative as v;ell as qualitative levels of a child's disability.7 Boder (1973) suggests a test battery that categorizes 3 different types of dyslexic in order of severity.5 (to be listed later) Pavlidis(1986) presents a testing technique measuring eye move1nen ts which may be used as a diagnostic tool to separate dyslexics from retarded readers.23 Yet anot11er diagnostic tests are published by White(1983), Jones (1986), and Hardman(1984) to name a few.(14, 16, 31) The Optometrist needs to be aware of, and understand which of these various testing/diagnostic procedures are being utilized in his community
-3- t•
in order to provide n1aximum assistance in the managen1ent of the child.
Despite the variety and direction of philosophies of the different disciplines, there are a few basic ideas that most of tl1e authors agree upon. In order to develop a successful prograrn of rernediation for the dyslexic an early diagnosis of the disorder is criticai. Boder(1973) has noted the variability in diagnosis of the dyslexic according to the different professions. She describes three general methods basic to rnost diagnostic formats.5 These rr1ethods include: 1. process of exclusion*- disadvantage of this method rests on the nature of the developn1ental dyslexic.5 As v arious other disorders are ruled out, the developmental dyslexic (DD) , w111c11 n1ay coexist w1ttl one of tl1ese disorders, may be ruled out as well.l *Note: tl1e exclusion criteria contributes t o a later diagnosis of dyslexia because/ it is based partly on a child's failure in school for C: a period of 2 'Jl.1 ...... , 23 -4- 2. indirect diagnostic approach- this method also tends to mask the DD which also coexists with the one or more disorders elicited 1n this technique and therefore can easily be overlooked.5 3. direct diagnostic approach- anal~lses the quality of er rors in reading and spelling which are characteristically seen with dyslexia.5 This method also may miss the DD because of the random occurrence of the dyslexic errors.18 Boder (1973) has also observed consistencies in these various methods as far as placen1ent of the dyslexia into distinct sub groupings. She also presents an alternative diagnostic approach based on the above "direct" approach which analyses reading and spelling patterns and places the dyslexic into 3 distinct categories.5 1. Dyseidetic- which is primarily a visual anornaly 2. Dysphonetic- which is mixture of a visual-auditory anornaly associated along with other articulation problerr1s. 3. l\r1ixed r)iseidetic-d}rsphol1etic- r-epresents a combination of tl1e first three sub groups. Griffin and Walton (19 8 1) expanded upon Boders subgroups t o come with a total of seven groups each with a specific set of signs and characteristic performance modes. The Dyslexia Detennination -5- Test (DDT) differentiates the dyslexic child fron1 those who are behind 1n reading and spelling due to other causes. The DDT places the dyslexic into one of the seven categories mentioned above. Each category has a different prognosis for treatment along with suggested approaches for the actual intervention. The types of dyslexia as given by the DDT are:11 1. Dvsnemk1net1c- Deficit in the ability to develop rnotor gestalts for written syn1bols. 2. Dysphonet1c- Deficit in symbol sound, and the ability to develop phonetic word analysis synthesis skills. 3. Dyseidet1c- Deficit in tl1e at>ility to perceive whole words as visual gestal t.s. 4 . Dysphone1det1c- Deficit in grapheme phoneme integration and in the ability to perceive whole words as visual gestalts, and match with auditory gestalts. 5. Dysnerr1kinphonet.ic-. Deficit in the ability to develop integration. 6. Dvsnernkineidetic- Deficit in the ability to develop rnotor gestalts for v-,rritten syrr1bols and in t:he ability t o perceiv e whole words as visual gestalts and match with auditory -6- gestalts. 7. D1snemk1nphone1det1c- Deficit in the ab111ty to develop motor gestalts for v.rritten syrnbols, grapheme-phoneme integration and in perceiving whole words as visual gestalts and matcr11ng audaory gestalt.s.ll There has been rnuch debate over the use of eye movement recordings and their diagnostic significance in dyslexia.21,22 Pavlidis (1986) has noted tJ.-1at since learning disabled and dyslexics manifest many of the same types of reading/spelling symptoms, it is important to differentiate the two disorders.23 In the search for an objective test of diagnostic validity through eye moven1ent recordings, researchers have come up with a number of differences in overall research design and procedures.25 Because of these major inconsistencies, Pavlidis (1985) proposed to establish a Research Diagnostic Criteria for Dyslexia (RDCD) in order to mat.e it possible to effectively compare the results of the various researct1 groups. The RDCD would n1ake it possible to better understand d~l·slexia and Provide the practitioner w1t:r1 sound information on which to base diagnosis and treatn1ent.22 -7- Controversy in Optornetry In 1972 the American Acaderny of Pediatricians, The A1nerican Acaqen1y of Ophthalmology and Otolarangology, and The An1erican Association of Ophthalmology issued a .Joint statement titled, "Eye and Learning Disabilities" .9 Tt"Ie statement addressed areas such as vision training, and prescribing glasses for- the learning disabled. A rebuttal to the above statement by Nathan Flax (1973) points out the inappropriate use and rnisinterpretation of the references cited. In conclusion of the paper Flax relates_, "The dissen1ination of this staten1ent as a conclusion of The American Academy of Pediatricians, The American Acaderr1 y of Ophthalology and Otolarangolog:,.r and The Arnerican Association of Ophthaln1ology does a- disservice to the public and represents an affront to the academic community. The position paper atternpts to discredit vision training and the use of glasses in cases of dyslexia. Almost all the references offered had nothing to do with the topic. The few which are germane actually support a positive relationship between vision and learning disatJilit1es. At the very least, better scholarship and intellectual honesty is to be -8- expected of these organlzat1ons"9 In 1981 The An1erican Academy of Ophthaln!ology, supported by The Arnencan Acaaerr"Ly or PedlatnClans, Tl'H? American Academy of rn'ihth""".£-'..I..L\.-.L.L'-'f...L.A..&..LV.A.Vb)') ~ lrnnlnov ar1d The A111er1·r.... U:':>.n Association for Pediatric Ophthalmology and Strabisrrn.ts, published another statement quite synonymous to the preceding state1.:-1ent of 1972. Part 4 of the most recent statement is of particular importance to the Opton1etrist. It reads, 11 4 . Correctable ocular defects should be treated appropriately. However, no known scientific evidence supports claims for improving the academic abilities of the dyslexic or learning disabled children with treatment based on : (a) visual training, including rr1uscle exercises, ocular pursuits or tracking exercises, -or glasses (Vv"1th or vvlttwut !)lfocals or p:r1:3rn~;) (l:i) nc:·urolog.lcf-.1 o:rg.fH11Zat.lonal training (lateral training,, balance board, perceptual training) Furtherrnore such training frequently yield deleterious effects a false sense of security is created which may delay or prevent proper instruction or n~·rnediation. "10 Flax et al (1984) again examine this staternent and the poor 1nterpretation of the references. A closing staterr1ent says, -9- "Evolution of the learning disabled child is traditionally multi disciplinary. It is important to deal with any defect or pro l:>lern that may be either causal or contributory to the child's problem. The policy staternent itself supports the interven tion necessary to correct any Sl.lCh problem. It is therefore illogical for the ad hoc committee not to endorse vision tra ining as a necessity in those cases where defects in visual function such as binocular fusion, accommodation, and ocular motor deficiencies interfere with the ability to respond to edu cational re1nediation. "10 Treatn)ent Diagnosis and treatment of a visual perceptual problen1 are usually directed and carried out by the educational con1munity. 8 However, optometrists, who support and follow the concepts of the OEP, COVD, and other such disciplines related to Behavioral Optornetric training, are also qualified to help children irr1prove visual perception. The role of the Optometrist is to respond within the limits of his expertise anc; knovtledge when managing the child -10- who has a learning deficit. Efficient diagnosis, treatrrHznt, and /or referral depends on expedient decision making.29 Silver (1987) has reviewed the current treatments available for the patient diagnosed as learning disabled or dyslexic. Therapies which are presently available include:28 Generally accepted -Special Education -Medication -Psychological Controversial -l\Ieurophisiological Retraining a. patterning b. Optometric Vision Training -Vestibular Dysfunction -Applied Kinesiology a. cranial faults b . cloacal reflexes c . ocular lock -ortr10rr10lecular n1edicine a . megavitan1ins b. trace elements c. hypoglycen-lia -11- ( ) Again we see Opton1etric intervention falling under the category of "controversial", Supporters of the statement by the American Academy of Ophthalmology (1981) disclaiming vision training as a viable option to_ the treatment of dyslexia, include I-...1etzger an ~v\Terner (1984) who also conclude that reading disabilities are not effected by problems in the visual systern.OO, 19) However, it is the opinion of several authors that the purpose of the optometrist or the eye care professional is to rule out the visual problerns of the learning disabled and refer to the other appropriate professionals for care. Vision Training Learning disabilities and dyslexia are not one one diinensional school problems and 1nost often they require a n1ultidisciplinary . approach to treat.n1ent.Z6 Research supports a potential role for opt.on1etrists in lreating the processing, perceptual, and eye rnovement deficits present in some subgroups of dyslexia.(26, 12) Seiderrnan (1980) investigated the effect of Opton1et1~1c Vision -12- Training on children identified as having learning disabilities with accornpany1ng visual problems and found that appropriately applied vision training enabled the children in this particular study to respond rnore effectively to reading instruction and school learning.24 However, there is a strong opposition to the use of vision training in the treatment of dyslexia as presented earlier by the staternent of the Arnerican Academy of Ophthalmology (1981).10 Metzger (1984) has examined the ophthalmological, optometry, and psychological literature on the effects of vision training on the learning disabled. In his concluding staternents he states ... 19 "There is no general agreement on the casual factors in reading disabilities, it is clear that ocular factors are, at best, rninimally related. It is possible that even the original theories are incorrect, that visual-perceptual training might still r1elp poor readers read better. However, when this possibility was anqlyzed, it was found ( that visual-perceptual training programs produce no further improvement in reading ability for the affected children v-1hen con1pared "\.\rith reading ability of children control groups" 19 -13- i ' Keogh (1985) addresses the questions about the efficacy of vision training on learning disabled and notes the existence of Opto-metric literature that successfully links vision with acaderrlic perforrnance. She also cites the work of researchers in other disciplines that contradicts the Opt01netric reviews. The author asks," ... for whom is vision training?" 17 The Dyslexia Detern1ination Testll enables a nurnber of practitioners to differentiate the child who presents with dyslexia from those children who are behind in reading, writing, and spelling due to causes other than dyslexia.12 Prognosis of intervention can also be determined according to the category to \vhich the child has been assigned. The seven dyslexic patterns are each assigned specific trai_ning techniques and the professional who would be the rnost appropriate to carry out the therapies. Griffin consolidates suggested training areas as follows: 11 DYSNEMKINESIA DYSPHONESIA DYSEIDESIA DYSPHONEIDESIA Develop: A. Laterality Develop grapheme- Develop integration Develop grapheme and . phoneme integration. of visual and audi- phQneme integration B. Directionality (matching visual tory gestalts. and integration of components of words (matching of vision visual and auditory c. Memory of with appropriate configurations of gestalts by memory Movement sounds). words with total of movement training sound patterns). (writing). D. Vision Perception 1. numbers 2. letters The remaining sub groups of dysnemkinphonesia, disnemkineides1a, and dysnemkinphoneidesia are patterns that represent combinations of the other four groups and should be 1nanaged accordingly. Conclusion We have merely skimmed the surface of the very controversial topic of dyslexia and the role of Opton1etry. Philosophies on defining, diagnosing, and treating the problem are variable and many times inconsistent when comparing across professions. Optometric intervention is not excluded from a possible approach to aiding the dyslexic patient however, the Optometrist needs to decide w11ere his or her limits are with this intervention. Ho~..v involved does the Optornetrist become v.rhen presented with the dyslexic or possible dyslexic patient? Recornmendations of this author bas'?d on information gathered fron1 the literature include ... 1. The Optometrist needs to make the decision as to the extent of diagnosis, intervention, and or referrals when dealing with the dyslexic patient based on the scope of that particular practice. Adler (1985) said, "It is important that professional skills are used to their fullest but care n1ust be exercised to avoid straying into areas where a full and -15- proper training course has not been undertaken. This will avoid offering inappropriate and conflicting advice and applies as much to Optometrists as it does to teachers, psychologists etc."2 2. The Optometrist needs to find out the general community philosophies of the various area education, psychological,_ and medical specialists on the management of the dyslexic patient to determine what role Optometry plays in the scheme of things. 3. Educate the public and other professionals as to the ser- vices that can be provided by the Optometrist in the management of dyslexia and the learning disabled. 4 . Develop a multidisciplinary scheme with the other professionals in the area that will provide the most efficient care systern for early intervention. 5. If the Opton""letrist decides to manage dyslexic cases that :require vision training in any forrn should work hi close procedures for maxin1um return. 6. Probably rnost irnpo:rtant, the Optornet:rist as \vell as, the other professions need to keep abreast of current research for -16- new developments on dyslexia in order to keep the treatment program as efficient as possible. Closing Rerr1arks It was not the intent of the author to present specific diagnostic and treatment procedures for dyslexia. There are several techniques available and it is up to the practitioner as to which of these will be used if at all. There references provided in the appendices to help the professional in making these sort of decisions along with some background inforn1ation on dyslexia itself. -17- 1. Aaron, P.(~., and Phillips, S., A Decade of Research witr-I Dyslexic College Students: A Surnmary of Findings., Annals of Dyslexia, Vol.36, 1986. 2. Adler, P.M., Visual Dyslexia and Learning Disability ., Optician, Nov. 29, 1985. 3. Allard, R.E., Binocular Vision Skills: Assessment and Therapy., Contemporary Optornetry, Vol. 4, #3, Oct. 1985. 4 . Beaucharnp, G.R ., Backround Inf0rrnation: Learning Disabilities, Dyslexia, and Vision., Journal of Learning Dysabilities, Vol. 20, #7, Aug/Sept 1987. 5. Boder, E., Developrnental Dyslexia: a Diagnostic Approach Based on Three Atypical Reading-spelling Patterns., Developn1.ental l\t1edicine and Child Neurology, Vol. 15, 1973. 6. Critchle),r, M.,(1970), Tr1e Dyslexic Child., The White Friars Press Ltd., London and Tonbridge. 7 . Dobbs, B."J., Bender, lVl., and Goldberg_, H.K., The Educational Diagnostic Evaluation of the Learning Disabled Child., "Journal of Pediatric Ophthalmology and Strabismus, Vol. 17, #3, 1976 . 8. Derby, C., "Vision" problen1s and reading disability: A dilemma for the reading specialist., The Reading Teacher, April 1979. 9 . Flax, N., The Eye and Learning Disabilities., Journal of Learning Dysabilities, Vol. 6, #5, IY'Iay 1973, pp. 328-333 10. Flax, N., Mozlin, R., and Solbn, A., Discrediting the Basis of the Arnerican Acaden1.y of Ophthalrnology Policy, Learning Disabilities, Dyslexia, and Vision., Journal of the Arnerican Opton1etric Association_, Vol.- 55 #6, "Jun 1984, pp. 399-403. 11. Griffin, J., and Vv·alton, H., Dyslexia Determination Test (DDT) , Examiner's Instruction Iv1anual, (1981), I-MED() Instruction Materials and Equiprnent Distributors, Los Angeles, Ca. -18- t! 12 . Griffin, J., and Walton, H., Therapy in Dyslexia and Reading Problems Including, Vision, Perception , and Motor Skills., (1985), I- MEDr Instruction 1V1ater1als and Equiprr@nt Distributors, Los Angeles, Ca. 13 . Haddad . H.M ., Isaacs, N.S., Onghena, K., and Mazor, A., The Use of Orthoptis in Dyslexia., Journal of Learning Dysabilities, Vol. 17, #3, 1V1arch 1984. 14 . Hardrnan, P.K ., The Training of Psycho-Educational Technicians (Para-Professionals) to Adrninister a Screening Batery Which Delineates Dyslexia and Hypertinesis.,Journal of Learning Dysabilities, Vol. 17, #8, Oct. 1984. 15 . Helveston, E.M., Vol III l'v1odule 1: Management of Dyslexia and Related Learning Disabilities.,Journal of Learning Dysabilities, Vol. 20, #7, Aug/Sept 1987. 16. Jones, B.H ., The Gifted Dyslexic., Annals of Dyslexia, Vol.36, 1986 . 17. Keogh, B.K ., and Pelland, M .. Vision Training Revisited., Journal of Learning Dysabilities, Vol. 18, *'4, April 1985 . 18 . Laudon, R.C., Optometric Evaluation and Therap)l for the Learning-Disabled Child., Conte1npory Optometry, Vol. 5, #3, Aug. 1986. 19. Metzger, R.L, Werner, D.B., Special Article: Use of Vision Training for Reading Disabilities: A Review., Pediatrics, Vol.73, #6, ...June 1984. 20. Miles, T.R.,and Haslun1, 1\1.N., Dyslexia: Anomaly or Variation?, Annals of Dyslexia, Vol.36, 1986. 21. Pavlidis, G.T., Erratic Eye l'v1overnents and Dyslexia: Factors Determining Their Relationship., Perceptial and Motor Skills, #60, 1985. 22 . Pavlidis, G.T., Eye 1V1ovements in Dyslexia: Their Diagnostic S1gn1f1cance., -.Journal of Learning D)tsabilities, Vol. 18, #1, -.Jan. 1985 -19- 23 . Pavlidis, G.T., Eye lv1oven1ents: The Diagnistic Key To Dyslexia?, Conternporary Opton1etry, Vol. 5, #2, April 1986 24. Seiderman, A.S., Optometric vision therapy- results of a den10stration project with a learning disabled poplation., ,..Journal of the American Optometric Association., Vol. 51, May 1980 25 . Simons, H.D ., Grisham, D.J., Vision and reading disability: Research Problenrs., Journal of the American Optometric Association., Vol. 57, #1, Jan. 1986, pp. 36-41. 26. Solan, H., Learning d1s1bil1t1es: The importance of considering sub-types in Optometric Research., Journal of the An1erican Optometric Association., Vol. 57, #1, .._Jan . 1986, pp. 15-16 . 27 . Stein, N.L., Lost In The Learning Maze., Journal of Learning Dysabilities, Vol. 20 #7, Aug/Sept. 1987, pp. 409-410. 28 . Silver, L.A., The "J\.1agic Cure": A Review of the Current Controversial Approaches for Treating Learning Disabilities., ....Journal of Learning Dysa.bilities, Vol. 20, #2, Oct. 1987 29 . Suchoff, I. B., Petito, T.G., The efficacy of visual training: Acconrmodat1ve disorders and non-strabismic anomalies of binocular vision.,Journal of the Arnerican Optometric Association., Vol. 57, #2, Feb. 1987 30. Thomson, M., Developmental Dyslexia., (1984), Edward Arnold Publishers Ltd., London. 31. White M ., Identification of Dyslexia: A Ninety-I\1inute Procedure, ,Journal of Learning Dysabilities, Vol. 16, #1, Jan. 1983 32. Wischler, C. R., The N:ooptropic Concept and Dyslexia,Annals of Dyslexia, Vol.36, 1986, pp. 118-137 33. Wold, R., Pierce, J ., Keddington, .... J. , Effectiveness of Optornetry Vision Training, Journal of Learning Dysabilities:. Vol. 49, #9, 9/78 -20- Appendix Flax, N., Visual Function in Dyslexia., American Journal of Optometry and Archives of American Academy of Optometry, Vol. 9, Sept 1968. pp. 574-586. Frith, U., A Development Framework for Deve1opn1ental Dyslexia.,Annals of Dyslexia, Vol.36, 1986 . Herman, H.T., Sonnabend, N.L, and Zeevi, Y.Y., Bihemifield Visual Stimulation Reveals Reduced Latera: Bias in Dyslexia., Annals of Dyslexia, Vol.36, 1986. Herrin, S., Is There Hope For Vision Training., Review of Optometry, Vol. 122, *5, May 1985. Levi, G., Piredda, M.L, Semantic and Phonological Strategies for Anagrarn Construction in Dyslexia., ,Journal of Learning Disabilities, Vol. 19, *1, ,.Jan . 1986. Ludlam, Vv.I'v1 ., Twarowski. C., Ludlam, D.P., Optometric Visual Training for Reading Disability- A Case Report., American Journal of Optometry and Archives of American Acaderny of Optometry, Vol. 2, #1, Jan. 1973. Ritty, IVI.J ., Assessing and alleviating visual problems -in the schools., The Reading Teacher, April 1979 Rosner, J., Ludlum, W., and Pierce, J., Optometry and Learning Disabilities, A Journal Interview., Journal of the American Optometric Association., Vol. 45, *5, May 1974 Vellutino, F., Dyslexia: Tl1eory and Research., (1979), The Alpine Press Incorporated, USA .