Dyslexia: Definitions and Theories - Essay Example

work] Dyslexia: Definitions and Theories INTRODUCTION There is currently no agreed definition or theory of Dyslexia. As such, the construct is worth studying and looking into because of several implications, primarily diagnosis issues. This paper investigates the various definitions and theories given for this syndrome, and discusses the advantages and disadvantages of such definitions and theories. It proceeds into the impact upon identification and assessment of dyslexia, then the main characteristics of the disorder, and finally the implications of labelling for the child/young person, parent and professional. Dyslexia research has a broad scope covering developmental dyslexia, in which reading skills has not matured properly; and acquired dyslexia, in which dyslexia originates as a brain insult causing disruption of an already established skill, like reading (Gardiola 2001). Several definitions of dyslexia revealed that reading deficits is the only common symptom among all of them (Doyle 1996), therefore, this paper's scope is focused more on such problems as related to dyslexia. Although varying in approach and interpretation of dyslexia, researches done by Beech (2005), Fisher & DeFries (2002), Habib (2000), Helland, Turid & Asbjornsen (2003), as well as those by Lachmanni & Geyer (2003). Needle, Fawcett & Nicolson (2006), Perry & Rice (1999), Davis & Braun (1995), Sawyer (2006), and Singleton (2005) invariably referred to reading deficit as common symptom of dyslexia. The same is true with those of Vellutino, Fletcher, Snowling, & Scanlon (2004). Although references have been accorded to some researchers of dyslexia, the bulk of these discussions here have been sourced from Gardiola (2001) who has so far covered extensively the history of dyslexia and its genetic etiology or the study of its cause. The paper ends with the hope that with the recent proliferation of theories and studies now, the main genes influencing the development of reading and dyslexia will soon be known. the Definitions and theories Bright solutions (2007) gives three definitions of dyslexia. Before the National Institutes of Health began their research in the 1980's, the only definition of dyslexia was said to be an exclusionary one. If a child's difficulty with reading could not be explained by low intelligence, poor eye sight, poor hearing, inadequate educational opportunities, or any other problem, then the child must be dyslexic. That definition, however, did nor please parents, teachers, or researchers. Simple and revised definition. Accordingly, the simple definition says dyslexia is an inherited condition that makes it extremely difficult to read, write, and spell in one's native language, despite at least average intelligence. On the other hand, the revised definition from the International Dyslexia Association is that - Dyslexia is a neurologically-based, often familial, disorder which interferes with the acquisition and processing of language. Varying in degrees of severity, it is manifested by difficulties in receptive and expressive language, including phonological processing, in reading, writing, spelling, handwriting, and sometimes in arithmetic. Research definition. Finally, the research definition used by the National Institutes of Health is that - Dyslexia is a specific learning disability that is neurological in origin. It is characterized by difficulties with accurate and/or fluent word recognition, and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge. Organizational definitions. Dyslexia is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities (Bright solutions 2007; Stanberry 2003). Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge. These are the definitions adopted by the IDA Board, November 2002 and by the National Institutes of Health, 2002. Meanwhile, the Learning Disabilities Association of America defines dyslexia as a learning disability in the area of reading (Stanberry 2003). This is the same outlook of the Bristol Dyslexia Centre of UK and the British Dyslexia Association. Critique on definitions and theories The simple definition is too simplistic and yet does not explain how it might be countered because the cause of the difficulty is not explained. The revised definition from the International Dyslexia Association, although it is more developed than the simple definition, does not link matters to learning. Why talk of difficulty in the first place What is it for In contrast, the research definition from the National Institutes of Health is comprehensive enough from cause to relationship with learning. The research definition provides the characteristics that could identify the malady, explains how the difficulties come about, and relates it to activities that the lacking abilities in dyslexia are supposed to fulfill - for example, learning. Definitions, therefore, that link the disability to learning are more persuasive and find much support in education circles. They are the most useful ones because they suggest a direction as to actions to be taken and the purpose and need for correcting such disability. The theories in dyslexia are roughly divided into Neurological/Sensory and Cognitives as discussed by Guardiola (2001). The first has to do with are visual deficits, auditory deficits, and neurobiology and brain structures. Under the second are involved the speed of information processing, and memory deficits. The first have to do with the physical Visual deficit theory. This theory has been criticized for lack of valid evidence, and with experimental data that could not find differences between normal readers and reading disabled children. This theory includes the erratic eye movements suggested by some researchers that dyslexics exhibited erratic eye movements while reading, the eye convergence deficits that claims that dyslexics' problems involve eye convergence and binocular control which could be related to a neurological deficit that impairs efficient information processing, the color lenses introduced by Helen Irlen, of the Irlen Institute in the US, to ease reading in some children, and finally, the magnocellular system hypothesis that believes that a slow or irregular functioning of the magnocellular pathway of the visual system could cause reading deficits. The visual defect theory, therefore, does not find enough support in research. Auditory deficits theory. Gardiola (2001) described Alfred Tomatis as proposing his auditory transcription deficit at the end of the 1960s in France. Accordingly, he suggested that dyslexics have difficulties transcribing written words into their phonological representations. His emphasis was in the auditory system, not in language deficits. The auditory deficits theory of dyslexia therefore does not have a foothold in science and should be altogether discarded. Neurobiology and brain structures theory. In 1937, Orton (In Gardiola 2001) had originally suggested the existence of instability in the cerebral dominance of linguistic functions, and also in hand or eye preference. According to this thought, if the brain areas involved in language are balanced between both hemispheres, dyslexics might need more inter-hemispheric communication, slowing their language processing, according to the cerebral dominance belief. The implications of these anomalies for dyslexics are not clear yet, according to Gardiola (2001). Neurological difference. Under neurobiology and brain structure theory, Stanberry (2003) more clearly explains interestingly dyslexia as resulting from a neurological difference; that is, a brain difference (Stanberry 2003). People with dyslexia, he said, have a larger right-hemisphere in their brains than those of normal readers. That may be one reason people with dyslexia often have significant strengths in areas controlled by the right-side of the brain, such as artistic, athletic, and mechanical gifts; 3-D visualization ability; musical talent; creative problem solving skills; and intuitive people skills. This neurological difference hypothesis is quite interesting and may be possible. Gardiola (2001) however said it does not find enough support in research as this may touch mainly on size and architecture of the brain. Cognitives theory. According to this theory, dyslexics make more mistakes than normal readers in auditory perception tasks that require quick stimulus discrimination. This finding suggested to Tallal, Miller, & Fitch (1995) that dyslexics have difficulties trying to perceive and process rapid information. This deficit is thought as the cause of the phonological deficits that dyslexics exhibit while reading. From all these deficit theories come the most supported theory which is that of Language and phonological deficits. Gardiola (2001) said theories, including those of Orton as early as 1937 and Liberman in 1971, claiming language deficits, mainly phonological, are mainstream in current cognitive psychology and linguistics agendas. Such deficits are said to impair learning to read and cause the dyslexics' reading mistakes and slowness where phonological awareness at age 4-5 predicts reading at age 9-10. This theory has a large number of followers and produces a large number of scientific studies each year. Advantages and disadvantages In terms of public awareness, Kristin Stanberry (2003) of the Charles and Helen Schwab Foundationwrote that in recent years, many famous and successful adults have gone public about their learning struggles, attributing a wide range of difficulties to "dyslexia." The advantage arising out of this publicity is that of rising public awareness of learning disabilities currently affecting millions of students. The bad effect to widespread publicity according to Stanberry (2003) is that the media, medicine, science, educators, and the law describe and define dyslexia in many different ways, making it hard for parents to gain a clear understanding of what dyslexia really is. In fact, it is commonly believed that a definition does injustice to dyslexia because it is so different in different cases. The use of many terms in reference to dyslexia, however, has its own advantages. It is fair to the patient some way because it pinpoints the exact problem instead of the all sweeping syndrome, "dyslexia" which even until now is debatable for lack of agreement between disciplines and scientist thinking. In education circles, for example, many educators don't use the term dyslexia but talk instead about specific learning disabilities or language processing disorders. It is because they believe dyslexia is a broad term which isn't very helpful in developing a targeted educational program to meet a child's individual needs. The impact on identification and assessment Diagnosing dyslexia is hard. The major clue is said to be the great difference between Intelligence Quotient and "reading" and "spelling age." This coupled with other symptoms typical to dyslexia that can clue professionals and others into an individual's disorder. Unfortunately, diagnosis is only half the battle. Dyslexia is said to be accompanied by constant academic failure, great feelings of inferiority, phobias relating to academics, and other psychological side effects. Singleton (2005) hints that there are educational and political climates that may be hostile to the concept of dyslexia, therefore being identified as a dyslexic may offer difficulties for the patient and his family. Stanberry (2003) has the following suggestions: When seeking help for your child, be sure to "consider the source" when you hear (or don't hear) the term "dyslexia" used. When communicating with your child's teachers, find out what terms they use to describe dyslexia so you can start "speaking the same language." As the legal, medical, and scientific references to dyslexia aren't always consistent with each other, specific questions must be asked. MAIN characterisitcs of the disorder The essential features of dyslexia are said to be difficulty over learning to spell despite adequate opportunity and intelligence, difficulty over learning to read, difficulty in some tasks involving awareness of left and right, difficulty over arranging things in correct temporal sequence, difficulty with certain kinds of items involving short-term memory, and sometimes difficulty over subtraction and difficulty in learning and reciting arithmetical tables. It must be stressed, however, that not all these symptoms exist in every dyslexic. Failure to recognize this fact may lead to problems. It is therefore expedient for experts dealing with dyslexia to have more comprehensive studies on this malady. Other symptoms that are usually related to dyslexia are character and word reversals. An example would be confusing p for q or d for b. However, outright assessment when letter reversals appear in a child's handwriting is not recommended. Also, boys, tend to suffer from dyslexia much more frequently than girls. Dyslexia is also thought to be a genetic trait running in certain families. These facts may aid in the pool of stock knowledge for dyslexia studies. Implications of labeling for child, parent and professional From the variety of ways the term "dyslexia" is used, it is hard to determine what is being talked about. However, it is clear that most do not like the catch-all nature of the term. Green, et al. (2005) examined the direct and vicarious impact of the social processes of felt and enacted stigma of being identified as a dyslexic and their impact on the lives of individuals with disabilities and their families. Analysing for themes related to components of stigma like labeling, stereotyping, separation, status loss, and discrimination within the context of power differential, the researchers found that these social processes can have important negative psychosocial consequences for individuals living with disabilities. What this clearly means is that it does not help to be merely labeling people as dyslexics. It was also found that these individuals find varied and creative ways to resist and actively counter the negative effects of stigma in their lives. On the research side, however, many well-known neurologists and scientists who conduct brain research tend to use the term "dyslexia." conclusion Whatever developments may come out from dyslexia research, what should not predominate is the conscious in-breeding of certain researches supporting certain theories. It is possible to abound in certain types of research espousing theories because funds are available only for that type and purpose, or that businesses arising from it like reading centers are supportive of it. Perhaps in the next decade, the main genes influencing the development of reading and dyslexia may be identified, where the deficits may be addressed by more direct therapies. As it is, only chromosomal regions, but not genes, affecting reading skills have been identified in research. References 'The dyslexia debate continues.' Psychologist. Volume 18, Part 12 (December 2005). Pp. 728-730. Beech, J. R. 'Ehri's model of phases of learning to read: a brief critique.' Journal of Research in Reading. Vol. 28 (1), 50-58. doi:10.1111/j.1467-9817.2005.00252.x. February 2005. Bright Solutions for Dyslexia, LLC. April 25, 2007. Available at: http://www.dys-add.com/define.html Davis, R.D. & Braun, E.M. Education vs. Child Development. 'How Dyslexia Happens.' The Dyslexic Reader. April 22, 2000. Available at: http://www.dyslexia.com/library/edart.htm. First Printed in The Dyslexic Reader.1995. Doyle, J. (1996). Dyslexia: An introductory guide. San Diego, CA: Singular Publishing Group, Inc. Fisher, S. E. & DeFries, J.C. 'Developmental Dyslexia: Genetic dissection of a complex cognitive Trait.' Nature Reviews. Neuroscience. Vol. 3. October 2002. doi:10.1038/nrn936 Green, S., Davis, C., Karshmer, E., Marsh, P. & Straight. B. (2005) 'Living Stigma: The Impact of Labelling, Stereotyping, Separation, Status Loss, and Discrimination in the Lives of Individuals with Disabilities and Their Families.' Sociological Inquiry 75 (2), 197-215. doi:10.1111/j.1475-682X.2005.00119.x Guardiola, J. G. 'The evolution of research on dyslexia.' Anuario de Psicolog__a, 32(1):3-30 (2001). Institute for Behavioral Genetics and Department of Psychology, University of Colorado, Boulder, CO, EEUU. April 23, 2007. Available at: http://ibgwww.colorado.edu/gayan/ch1.pdf Habib, M. 'The neurological basis of developmental dyslexia. An overview and working hypothesis.' Brain, Vol. 123, No. 12, 2373-2399, December 2000. Oxford University Press. Helland, T. & Asbjornsen, A. 'Visual-Sequential and Visuo-Spatial Skills in Dyslexia: Variations According to Language Comprehension and Mathematics Skills.' Child Neuropsychology, Volume 9, Issue 3 September 2003 , pages 208 - 220. DOI: 10.1076/chin.9.3.208.16456. Lachmanni, T. & Geyer, T. 'Letter reversals in dyslexia: Is the case really closed A critical review and conclusions.' Psychology Science, Volume 45, 2003, p. 50-72. Needle, J. L; Fawcett, A. J. &. Nicolson, R. I. 'Balance and dyslexia: An investigation of adults' abilities.' European Journal of Cognitive Psychology, Volume 18, Issue 6 November 2006 , pages 909 - 936. DOI: 10.1080/09541440500412304. Nicolson, R. I. &Fawcett, A. J. 'Developmental dyslexia: The role of the cerebellum.' Dyslexia. Volume 5, Issue 3 , Pages 155 - 177. John Wiley & Sons, Ltd. September 10, 1999. Perry, C. A. & Rice, R. E. 'Network Influences on Involvement in the Hybrid Problem Area of Developmental Dyslexia.' Science Communication, Vol. 21, No. 1, 38-74 (1999). DOI: 10.1177/1075547099021001002. SAGE Publications. Sawyer, D. J. 'Dyslexia: A Generation of Inquiry. Topics in Language Disorders.' Dyslexia in the Current Context. 26(2):95-109, April/June 2006. Singleton, C. (2005). 'Dyslexia and oral reading errors.' Journal of Research in Reading 28 (1), 4-14. doi:10.1111/j.1467-9817.2005.00248.x. Stanberry, K. 'Defining Dyslexia: A Modern Dilemma.' Charles and Helen Schwab Foundation. April 14, 2003. April 27, 2007. Available at: http://www.schwablearning.org/articles.aspxr=709 Tallal, P., Miller, S., & Fitch, R. H. (1995). 'Neurobiological basis of speech: A case for the preeminence of temporal processing.' Irish Journal of Psychology, 16 (3), 194-219. Vellutino, F. R.., Fletcher, J.M; Snowling, M.J. & Scanlon, D.M. (2004) 'Specific reading disability (dyslexia): what have we learned in the past four decades' Journal of Child Psychology and Psychiatry 45 (1), 2-40. doi:10.1046/j.0021-9630.2003.00305.x Read More