Dyslexia, which is also known as specific reading disability, is a complicated condition. Issues surrounding dyslexia such as how and why it occurs and how it can be assessed and treated are constantly being discussed. This condition has various characteristics but not all of them affect every person who has dyslexia. Thus, it has been impossible to agree on a conclusive definition of dyslexia. However, it can be said that phonological defect is strongly related to the condition of dyslexia. In this essay the controversial points over the main causes of dyslexia will be outlined and discussed. The second part of the essay will discuss the discrepancy tests which are used to diagnose dyslexia and their reliability will be measured. The third part of the essay will relate the causes to intervention. This will be followed by an explanation of Fast ForWord, (a method of intervention) and a discussion of how effective this is for children with dyslexia and some criticism for this kind of intervention method.
The term dyslexia
Dyslexia has previously been diagnosed as blindness and it was thought to be a medical problem (Lawrence, 2009). Dyslexia is currently defined as a learning difficulty, or more specifically reading difficulties. According to Hornsby (1984), the word dyslexia comes from the Greek and it means problems with language, especially reading.
From my experience it may seem for some people the effects of dyslexia will not cross the school barriers, but indeed it goes further than that with the dyslexic person. For example, it takes a child with dyslexia much longer to work out the meaning of verbal instructions, therefore they respond more slowly. This is also the case for everyday life, not just at school (Lawrence, 2009). Such this problem with the child could affect his communication with his beer group, because he may not act as fast as non-dyslexic children and as a result that has a negative impact on his personality as well as his social life. I witnessed one example of dyslexia in a child in Saudi Arabia. This child isolated himself in his room most of the time and he never wanted to take part in any activities with his brothers (2 older and 1 younger) because they always tried to irritate him in many ways such as, coping his way in reading and shouting at him when he doesn’t respond to them normally. As a result of this, in addition to his parents ignoring the problem due to their lack of knowledge about it, over time he developed very low self-esteem and he ended up in isolation. There are obvious characteristics and signs of dyslexia in a child such as finding it difficult to learn the alphabet, being unable to recall patterns and the order of events, difficulties with reading, writing and spelling, issues with short-term memory, problems with recalling verbal instructions, confusing left and right and reversing the order of words in a sentence (Lawrence, 2009).
Yet, there are several reasons that make it difficult to notice dyslexia in a child. The first reason is that there is no guarantee that dyslexic characteristics will be obvious, as some children are very good at concealing their difficulties. The second reason is that indicators of dyslexia sometimes are very similar to those of other learning difficulties. Such as the learning difficulties which would result from the background of the family. (Lawrence, 2009). For example, my daughter is 2 years old and although it is too soon to confirm any potential learning difficulty, I have been told by her nursery that she is less capable than other children of the same age in verbal activities such as naming a substantial material for the child (bottle) or a pets (dogs and cats) in English. The reason for this is because we sometimes speak to her in Arabic and we sometimes talk to her in English. Therefore, we can’t be 100 per cent sure that she has a learning difficulty. Therefore, I firmly agree with Mr Lawrence that it is not easy to identify and assess the cause of dyslexia on the child. This leads us onto the question of what dyslexia is.
What is dyslexia?
As dyslexia covers such a large area it is not viable to have a single definition. This is for several reasons including the large variety of symptoms which manifest themselves in a person with dyslexia and the large number of stockholders in dyslexia (Lawrence, 2009). Therefore, it is evident that there are varying definitions of dyslexia that are in use. One definition is that it is a neurological condition with the existence of other problem such as visual and the auditory system deficit (Siegel and Smythe2004). Another suggestion is that it is caused by inefficiency in the process of the language in the brain and it is all has a genetic origin (Dyslexia action, 2007). An additional classification is that dyslexia is an amalgamation of abilities and difficulties that has impact in the learning process (The British Dyslexia Association, 2001). The following part of this assignment will expand on these definitions which related to the cause of dyslexia.
Is dyslexia genetic?
According to research it is possible that dyslexia could be genetic. This idea is supported by a study that was carried out on a large Norwegian family. The study showed that current members of the family had had problems with reading and spelling at school. This issue had also affected the two previous generations. Thus, researchers are of the opinion that dyslexia is genetic. Furthermore, a gene for dyslexia was found in chromosome 2 (Fagerheim, Paeymaekers, Tonnessen, Pedersen, Tranebjaerg and 1999). However, in my opinion it is still essential to take the family’s background and culture into consideration as these factors could contribute to the outcome of the studies. The significance of a family’s background is demonstrated in the following example. Where was the father occupation is the base, which resulted, despite the interpretation of the writer, the numbers of specific reading retardation children for unskilled parents were higher than those who have professional parents (Jorm, 1983). Moreover, if the parents find reading to be a difficult activity it is likely that this will be the same for their children. It is also imperative to consider children who have dyslexia but where there is no genetic evidence of this disability in their family history (Jorm, 1983). For the purpose of emphasis the genetic cause of dyslexia many twins studies were carried out and almost accounted for the genetic factor of the cause of dyslexia (Hulme and Snowling, 2009). However, Hulme and Snowling criticise the method which used in twins studies and claimed that these methods usually used to separate categories that are more typical of physical characteristics and they are not valid for children with reading problems (Hulum, et al., 2009). Interestingly, some researchers have compared a test results for twins with reading difficulties and found out that although there are a similarities also a big differences was found between the twins’ scores in the test (Hulme, et al., 2009). However, there are other theories about the cause of dyslexia, including the Mangnocellular Hypotheses which will be examined in the following part of this assignment.
Is dyslexia caused by a vision deficit? (Magnocellular Hypotheses)
A vision deficit was suggested to be one of the causes of dyslexia. Stein and Walsh (1997) claimed that a sensory defect in the large nerve cells (magnocells) in the eye could be a reason of dyslexia. The role of these cells is to deliver information for quick movement and if the image in these cells becomes unstable, the organization of processing print or symbols will be affected. However, it is important to question whether this is really a cause of reading difficulties because even a normal child could experience the same visual issue when he or she starts reading, for example swapping round the letters “b” and “d”. Moreover, adults when in an embarrassing situation such as a presentation could change an entire word. For example, I once read strategies as stages in a presentation. Therefore, it is normal for a child with reading difficulties to make what appear to be visual mistakes when reading. The argument about the cause of dyslexia will continue to the next topic of the discussion which would be the auditory deficit theory.
Is the auditory deficit theory the cause of the problem in dyslexia?
It has been said that dyslexia could also be caused by auditory problems because people with dyslexia often mix up the sequence of syllables and numbers when they hear them out loud. This is because of the manner in which the brain translates the nerve impulse sent by the ears. With normal people, the right ear is usually responsible for interpreting speech sounds because it is connected to the left hemisphere (which specialises in language). However, often this is not the case with dyslexic person which could be the cause of the problem in dyslexia (Nicolson and Fawcett, 2008). According to Thomson and Watkins (1990), people with dyslexia tend to have issues with sequencing skills, especially when they have to determine sounds. Therefore, when taking the research that has been conducted on this area into account it appears that auditory perceptions could be one of the causes of dyslexia. Tallal and Piercy (1973) have conducted man experiments which is the result supports the auditory deficit theory and refer the reading deficit to an origin of auditory perception deficit. They claimed that the auditory deficit will lead to speech perception and then to phonological deficit which in the end would result a reading deficit. This suggestion will be compared to an opposing theory in a later section of this assignment.
The dominant theory of dyslexia
The phonological deficit was found as a main problem in dyslexia in a wide variety of studies. Many researchers in this field have conducted a lot of studies with the aim of uncovering the primary cause of the disability. The result of these studies was that dyslexia is caused by a cognitive deficit that is particular linked to the process of speech sound (Bryant and Bradley,1985). This theory is called the phonological theory of dyslexia. Words are consist of units of sound which can be connected together to generate words. According to Bryant and Bradley (1985), in order to be aware of words you first have to divide the speech stream information. Conversely, normal readers have the ability to get the information they into words, then segment the words into phonemes. Experts have discovered that children with dyslexia find it difficult to retain phonological need from their memory without having to think about it consciously (Bryant, et a.l, 1985). Nicolson and Fawcett (2008) believe that children with this disability have problems with accessing the information that is stored in their memory. Therefore, it is evident that children with dyslexia will find it difficult to read new words. Thus, this issue will not affect normal readers, as they will be able to consult their memory to access the necessary phonological information (Snowling, 1995). Although there are other conditions such as reading impairments or an auditory deficit that match this theory, they are not really relevant to children with dyslexia.
There are several different indicators of phonological deficits that are present in children with dyslexia before the reading age. Examples include pronunciation difficulties between the ages of 2 and 5 and problems with naming objects at the age of 3 (Scarborough and Dorbrich, 1990). Potential dyslexia can be determined from listening to a child speak. Sometimes it is possible to hear that a child’s phonological skills are not developing as they should be. That due to the complexity of everyday language which has an impact on a child’s ability to learn the names and sounds of the letters in the alphabet and their capability to pronounce specific words (Shaywitz, 2003).
Phonological Deficit and the Auditory Deficit
A comparative study was carried out on normally developing children and children with learning difficulties to determine whether there was a link between phonological deficits and auditory deficits. The study required both groups of children to complete an auditory repetition task. The outcome was that the group of children with learning difficulties found it more difficult to complete the task than the group of normally developing children (Talla, et al., 1973). However, after considering the results of the study, it was concluded that an auditory deficit could not be the cause for the phonological deficit found in children with dyslexia (Hulme, et al., 2009). This conclusion came about because the group of children with learning difficulties also had oral language difficulties. Therefore, this indicates that the auditory deficit is associated and linked strongly with language difficulties and not particularly to reading difficulties (Hulme, et al., 2009).
The Hemisphere Theories
Another related fact in defining the problem in dyslexia is the function of the hemisphere. The brains of both people with dyslexia and normal readers appear to be different from each other. REsearch harR Research has shown that there is a relationship between the way a brain is organised and dyslexia. The brain consists of two hemispheres, each of them has different roles, the left hemisphere is linked to the verbal tasks whereas, the right hemisphere is linked to other tasks. It is common knowledge that children use the left side of their brain to acquire information (Galaburda, 1989). A comparative study on adults with dyslexia and adults without this condition discovered that the right hemisphere of the brain is larger in individuals with dyslexia; however the left hemispere is larger in people without dyslexia (Galaburda, 1989). This could be the interpretation to the problem in dyslexia. In relation to the results of this study, Miles (1974) carried out an experiment which showed that in the brains of people with dyslexia language was spread more equally over the two halves of the brain. Therefore, there is an increased number of messages which are transferred from one side of the brain to the other, which can cause a mass in the nerve signals while connecting the two language areas in the brain.
Furthermore, it was proved that the responsibility for the coordination and physical activities for example, movement and balance is linked to the cerebellum in the brain. Fawcett and Nicolson (1994) have demonstrated that there is a significant link between phonological issues and motor skills. Even though a link has been established between the cerebellum and dyslexia, the establishment could not conclusively determine whether this is the principal cause of dyslexia (Lawrence, 2009).
It must be noted that research into the brain differences of people with dyslexia and normal readers is still relatively new. Thus, even though some studies have produced similar results, it cannot definitively consider the main cause of dyslexia. Moreover, it should be considered that people with dyslexia would have a less experience in reading then non-dyslexic, therefore, this would be interpretation for the different structure and function of the area in brain which involved in reading. An important consideration is that the different in the brain construction and function in people with dyslexia could be the consequences for their lake of reading experience and not the cause of the deficit (Hulme, et al., 2009).
Yet, it seems that the facts overlap. Some of them could be the cause and a consequence at the same time. This is further explained in diagrams 1, 2 and 3.
and other symptoms such as responding to verbal orders and the size and deficit in left hemisphere in the brain.
A diagnosis of dyslexia
Auditory deficit leads to
the same consequences as in diagram 1.
A diagnosis of dyslexia
Factor leads to
The same consequences as in diagram 1 can be misinterpret-ed as a visual or auditory deficit.
Cognitive deficit “triangle model”.
Hulme et al., (2009) p. 63. Leads to
A diagnosis of dyslexia
The visual theory poses the same symptoms on children with dyslexia, as well as, including the characteristics in the diagrams above. The diagrams interpretations are not the only possible starting point for dyslexia, but they illustrate some of the possibility. After the discussion for the cause of the problem, the second part of the assignment will move to the assessment and diagnosis for it.
Assessment and diagnosis of dyslexia
In order to correctly identify a student’s requirements an educational diagnosis is essential. It is obvious that assessment and diagnosis have several advantages. The advantages of testing for dyslexia include making it possible for the stockholders to discover whether a child is dyslexic, determining a child’s strengths and weaknesses if they are dyslexic, finding out what symptoms they have and allowing the teacher to provide adequate support in the future (Klein, 1993). Simply put, carrying out a test would allow teachers to assess a child’s abilities. The next step would be to analyse the results of the test and to put the child in the most appropriate class and to provide a sufficient level of learning support. It is imperative that this is done carefully and for this reason several studies have been carried out to ensure the tests are accurate.
There are several tests that are used to determine whether a child has dyslexia or not, however the one which is most frequently used is the Weschler Intelligence Scale for Children (WISC) (Cotton, Crewther, Crewther 2005). However, it is really face a real criticism for its method in measuring the intelligence then makes a decision in replacing a child or labelling him. To illustrate, WISC uses two scales, the first one is verbal and the second one is performance which a general IQ would be taken out of them and a child who fell into under 1or 2 mince Standard Deviation will be labelled as a dyslexic and provide him with the support he needs (Thomson, 1990). However, it is quite difficult to judge the results of this test because children with dyslexia have problems with specific tasks that are found in intelligence tests, therefore this would have an unfair impact on their IQ. Consequently, it is very important to consider a child’s IQ carefully as this form of assessment is based on a general estimate of a child’s abilities and it just reflects the bottom line for this ability (Thomson, 1990). This is also true of the British Ability Scales. The BAS has a supplementary feature which calculates a child’s ability by taking various processes into account. These processes include some activities such as, reasoning or short-term memory. It is common for a child with dyslexia to have difficulties with short-term memory tests which might be a reason to believe this child only has limited abilities (Thomson, 1990). However, the results of this test are poor because each individual person’s abilities are subject to many factors such as the senses (visual and hearing), reasoning, cognition, and memory. When a dyslexic child has a deficit in one area, it is common for him/her to be less able in this area when compared to a non-dyslexic child.
Aaron in 1994 also holds the same opinion and has conducted research about the use of intelligence tests to determine reading ability. In general it can be said that intelligence tests are used to differentiate between children who do and do not have dyslexia by looking at their reading attainment. However, these tests are inconclusive because the real reading ability for the student it cannot be ascertained by the differences between the reading potential for the child and his attainment in reading. Moreover, even though a number of studies have reported that there is a relationship between reading achievement and IQ results, IQ accounts for few percentages of the variation found in the students reading attainment. In reality the majority of research studies have demonstrated that the relationship between IQ and reading achievement is negligible (Aaron, 1994). However, it is true that there is a relationship between IQ and how accurately a child can read but this cannot be applied some children who find it difficult to learn how to read at school. In addition to the relation between IQ and reading problem Hulme and Snowling conclude that, “From an educational perspective there is no evidence that children who have word level (decoding) reading problems will vary in their responsiveness to teaching according to their IQ level” (Hulme, et al., 2009).p39
Several researchers were sceptical about the accuracy of intelligence tests so conducted a study on a group of teenagers and young adults with dyslexia. The participants were initially tested then retested after six years later. Surprisingly, the outcome indicated a considerable decrease in verbal IQ, however this was on one hand attributed to the unreliable nature of the test. Yet, the level of performance IQ improved significantly. On the other hand, the research illustrated another interoperation as well rather than just the reliability of test, for example for the increase in the PIQ test this could be indication for the improvement in the visual skills or problem solving skills or any other skills for the student. The decrease in the VIQ test could be as a result of the dyslexic children who usually try to keep away from reading experience as well as some other experience such writing. Ultimately, intelligence tests should be used cautiously as the results could be used to make important decisions (Ingesson, 2006)
From time to time it is difficult to distinguish poor readers from children with dyslexia. This is where intelligence tests can be useful. To illustrate, if fifty subjects were tested, and half of them were diagnosed with dyslexia, then over a period of time, tested again, the non-dyslexic children will have improved more so than that of the child with dyslexia. It could then be assumed those children that improved were just poor readers for some reason, such as, from their environment, and they don’t have a deficit. This scenario could explain the discrepancies in the results of the studies that were conducted.
Even thought there are a lot of disadvantages for using the discrepancy test, there are many institutions around the world such as, the World Health Organisation and the Diagnostic and Statistical Manual of Mental Disorders both agree with using discrepancy models. However, the matter that needs to be considered is how they should be used. Moreover the error associated with the tests and the way it occurs should be recognised as well (Cotton, et al., 2005). In 2005 Cotton, et al. suggested ways to observe the test errors. It was mentioned that in the classic test theory, the observed score should consist of the error and the true score; the true score is assumed as real reflection for the child’s ability, which can be concluded from a test without restrictions. If the difference in the results between both tests observed and true was large that means there are a lot of errors. Furthermore, it is important to bear in mind how beneficial intervention and remediation programmes can be to a child with dyslexia if it is based on a correct result for assessment and the opposite is true. Thus, it should be imperative to reflect on measurement error when analysing discrepancy scores (Cotton, et al., 2005). The accuracy of assessment dyslexia is really crucial for the students as it was mentioned before. Therefore the assessment methods are always examined in order to avoid wrong diagnosis.
Indeed a wrong diagnosis could affect the entire family. For instance, the son of one of my relatives was diagnosed with dyslexia 2 years ago when he was 7 years old. He couldn’t speak very clearly and only his parents could understand him properly. Recently, my relative’s second child was diagnosed with dyslexia when he was in the first year of primary school. However, by the end of the first year he had made significant progress, so the special education teacher retested him. The results of the second test were very different from the original diagnosis and he showed a great improvement in all the parts of the tests. Further investigations were made which highlighted the fact that the family had been talking to him in the same way his big brother spoke, for example when the parents told the child to watch Tom and Jerry they would say watch TJ instead of saying do you want to watch Tom and Jerry. Let’s assume the first child was misdiagnosed as dyslexic and with this kind treatment from his parents he would probably get the same result for real dyslexic child in the test. Indeed, his brothers or sisters would also be affected by these circumstances. In this case I have really doubt about the first child diagnosis and the reason for him to not make any progress in the tests would be because the lake of the motivation to learn and he may want to stay always under his parents spoiled treatment and hating attending to school.
Due to the numerous possible causes of dyslexia an equal number of interventions have been suggested. In the first part of this assignment it was inferred that a child with dyslexia might have an abnormal brain structure which could mean the child would interpret sounds incorrectly. The results of a study on developmental dyslexia that used brain-imaging techniques support this theory. The outcome of the study indicated that children with developmental dyslexia find reading difficult because their brains cannot process the change in the sounds accurately. Another discovery that was made was that by utilising computerised sound training, the children with developmental dyslexia were able to tackle the problem in the brain. This training made it easier for the children with dyslexia to process sounds effectively, thus they would experience improvement in their problem to read (Gaab, Gabrieli, Deutsch, Tallal , Temple, 2007). Another difficulty that children with developmental dyslexia faced was making a connection between letters and their sounds. A child who does not have dyslexia can normally process sounds quickly, but if a child is dyslexic they can find it difficult to determine individual speech sounds speedily and thus they will mix up syllables and create an incorrect internal sound map. Hence, it is expected for them to have problems with phonetic skills. As previously mentioned, computerised training can be used to re-wire the networks in the brain. This intervention results in the strengthening of brain areas which were previously relatively weak. Thus, the symptoms of developmental dyslexia become less noticeable over time (Gaab et al., 2007). This would appear to be an effective method of intervention and has resulted in the production of numerous programmes to lessen the phonological deficit in children with dyslexia. An example which has produced positive results in children with dyslexia is a computer programme called Fast ForWord.
Fast ForWord was created by Tallal and several of her colleagues (Tallal, Mezenich, Miller & Jenkins, 1998). She stated that Fast ForWord can alter that way in which the brain understands speech and other auditory signals which makes it easier for a child with dyslexia to understand speech and language (Merzenich, Jenkins, Johnston, Schreiner, Miller, and Tallal, 1996). Fast ForWord uses a powerful computer program which concentrates on auditory processing and oral language. The main part of the program is that it encourages the dyslexic child to differentiate between fast auditory signals. Additionally, this program focuses on improving particulars skills on the child such as auditory and memory skills and the processing of the sound (Merzenich, Jenkins, Johnston, Schreiner, Miller, Tallal, 1996). Merzenich et al. (1996) believed that children with language difficulties are unable to recognize auditory signals at a normal pace. They have conducted a study on children with learning impairment. The subjects were engaged in computer-based exercises which designed to improve their temporal processing abilities. The students were subject to up to 16 hours during 20 days. In the end of the period the subjects showed a remarkable improvement on their abilities in responding to verbal and non-verbal activities. The outcome inferred that all the participants that had used Fast ForWord had a marked improvement in their ability to carry out auditory perception and sequence tasks. This indicates that their level of grammatical understanding had also improved due to the Fast ForWord programme.
Recently, several studies have been conducted on the Fast ForWord program to measure their impact on language impaired children, the results of which can be seen as follows. however, the children performance have improved in the end of the program, their improvement did not last forever but it just remained up to 2 years (Hook, Macaruso, Jones, 2001). Therefore the actual benefits of the Fast ForWord programme can be questioned. For example, how could this programme is used for children with attention deficit disorder? It is evident that children with attention deficit would find it difficult to focus on mission for long time and furthermore, this programme would be even more difficult to use for a child with both dyslexia and attention deficit disorder. Thus, this programme may not be of any benefit for some dyslexic children.
To conclude, when bearing in mind the various explanations for the cause of dyslexia it can be said that the majority of researchers agree that a phonological deficit very strongly linked to the cause of dyslexia and the area which it is most beneficial to work on. Conversely, several researchers do not agree with this explanation. While they accept that people with dyslexia do have a phonological deficit, they also infer that sensory aspects and genetics are also relevant to dyslexia. It is quite possible that all these aspects could be linked to dyslexia. It is important for researchers to overlook their different explanations because by doing they will be able to focus on a single cause of dyslexia which will lead to the creation of more effective methods of intervention.
It is true that there are a wide variety of ways to assess dyslexia; however some are more effective than others. One example is the discrepancy test, but this is notoriously unreliable and it does not accurately measure the degree of the deficit. Even though some intelligence tests have been criticised they are still used. A frequently employed test is WISC, however it is important to exercise caution when using this test as inaccurate results could lead to a child being placed in the wrong class which would have a significant impact on the child’s education. When the causes of dyslexia have been identified and an assessment has been conducted the next step is intervention. As there is no definitive explanation of the causes of dyslexia many intervention programmes have been created, one example of which is the Fast ForWord programme. It is important to note that further research needs to be conducted if a more effective method of intervention is to be created.