What Is Dyslexia Really?
Di dunia kini kita, tiap orang harus dapat membaca....
Unless one has FIRST learned to speak Bahasa Indonesia, there is no way that one would be able to read the above Indonesian sentence.
This shows that language is at the very bottom of the reading ladder. Its role in reading can be compared to the role of running in the game of soccer, or ice-skating in the game of ice hockey. One cannot play soccer if one cannot run, and one cannot play ice hockey if one cannot skate. One cannot read a book in a language — and least of all write — unless one knows the particular language.
If a child's knowledge of English is poor, then his reading will also be poor. Evidence that links reading problems and language problems has been extensively presented in the literature. Research has, for example, shown that about 60 percent of dyslexics were late talkers. In order to prevent later reading problems, parents must therefore ensure that a child is exposed to sufficient opportunities to learn language.
The second rung consists of cognitive skills
While language skills comprise the first rung of the reading ladder, cognitive skills comprise the second. There is a whole conglomeration of cognitive skills that are foundational to reading and spelling.
“Everyone knows what attention is,” wrote William James in his Principles of Psychology (1890). “It is the taking of possession by the mind in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought... It implies withdrawal from some things in order to deal effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state.”
Needless to say, attention or concentration (the words attention and concentration are used synonymously) plays a critical role in learning. Focussed attention is the behavioural and cognitive process of selectively concentrating on one aspect of the environment while ignoring other things, while sustained attention refers to the state in which attention must be maintained over time. Both are important foundational skills of reading.
Because attention is so important for reading, ADHD and dyslexia commonly co-occur. Approximately 25 percent of children who are diagnosed with ADHD, a learning difficulty known to affect concentration, are also dyslexic.
Visual perception plays a significant role in school learning, particularly in reading.
Visual perceptual deficit refers to a reduced ability to make sense of information taken in through the eyes. This is different from problems involving sight or sharpness of vision. Difficulties with visual perception affect how visual information is interpreted or processed. The person may have a difficulty to discriminate in terms of foreground-background, forms, size, and position in space. He may also be unable to synthesise and analyse.
- Foreground-background differentiation involves the ability to focus on selected objects and screen out or ignore the irrelevant ones. The child experiencing a difficulty in this area is unable to recognise an object which is surrounded by others. For example, the child cannot locate a ball in a picture of several toys, or a word in a word-find puzzle.
- Form discrimination: Whether it is to differentiate a circle from a square, or the letter B from P, the ability to perceive the shapes of objects and pictures is an important skill for the developing child to acquire. There is hardly an academic activity that does not require the child to engage in form discrimination.
The most obvious classroom activity requiring the child to discriminate forms is that of reading. The learning of the letters of the alphabet, syllables, and words will undoubtedly be impeded if there is difficulty in perceiving the form of the letters, syllables, and words. That the discrimination of letters is a crucial skill in the early stages of reading is evidenced by an extensive literature review conducted by Chall (1967). She concluded that the letter knowledge of young children is a better predictor of early reading ability than the various tests of intelligence and language ability.
- Size discrimination: Capital letters, being used at the start of a sentence, sometimes look exactly the same as their lowercase counterparts, and must therefore be discriminated mainly with regard to size. A person who is unable to interpret size may, for example, find it difficult to distinguish between a capital letter C and a lowercase c.
- Spatial relations refer to the position of objects in space. It also refers to the ability to accurately perceive objects in space with reference to other objects. A person with a spatial problem may find it difficult to distinguish letters like b, d, p, and q.
- Synthesis and analysis: Synthesis refers to the ability to perceive individual parts as a whole, while analysis refers to perceiving the whole in its individual parts. Synthesis plays an important role in reading, whereas analysis is of special importance in spelling.
Myklebust defines auditory perception as the ability to “structure the auditory world and select those sounds which are immediately pertinent to adjustment.” Berry and Eisenson state that children with auditory perceptual deficits can hear sounds but are unable to recognise them for meaning. Defined as the ability to recognise or interpret what is heard, auditory perception plays as important a role as visual perception in reading.
Problems with auditory perception generally correspond to those in the visual area and are presented under the following components:
- Auditory foreground-background differentiation refers to the ability to select and attend to relevant auditory stimuli and ignore the irrelevant. The child who has a difficulty in this area is unable to make such differentiation. As a consequence, everything heard is attended to equally. Thus, the teacher’s voice is lost in the background noises of other children’s whispers, or the voices in the corridor, or the traffic sounds coming from the street.
- Auditory discrimination refers to the ability to hear similarities and differences between sounds. The child who has a problem in this area is unable to identify gross differences, for example between a siren and a school bell, or phonemic difference as between the words /pen/ and /pin/ or /big/ and /pig/.
- Auditory blending. Also referred to as auditory analysis and synthesis, this is the ability to synthesise individual sounds which form a word. The child who manifests a difficulty in this area is unable to blend the individual sounds in a word, such as /c-a-t/. The child may know the individual phonemes but simply cannot put them together. Similarly, the child may have problems breaking apart an unknown word by syllables and blending it, such as /te-le-phone/.
Memory is the retention of information over time. Although the word memory may conjure up an image of a singular, “all-or-none” process, it is clear that there are actually many kinds of memory, each of which may, to some extent, be independent of the other.
- Visual memory involves the ability to store and retrieve previously experienced visual sensations and perceptions when the stimuli that originally evoked them are no longer present.
Most learning-disabled students have serious deficiencies in the area of visual memory, states Addie Cusimano in her book Learning Disabilities: There Is a Cure. Children who have not developed their visual memory fail to develop a good sight vocabulary and frequently experience serious writing and spelling difficulties.
- Auditory memory involves being able to take in information that is presented orally, to process that information, store it in one's mind and then recall what one has heard.
A poor auditory short-term memory is often the cause of a child’s inability to learn to read using the phonics method, says Cyndi Ringoen, a neurodevelopmentalist. “Phonics is an auditory learning system, and it is imperative to have a sufficient auditory short-term memory in order to learn, utilise and understand reading, using the phonics method.”
- Sequential memory requires items to be recalled in a specific order. Many learners with reading difficulties have poor visual sequential memory, i.e. a poor ability to perceive things in sequence and then remember the sequence. Naturally this will affect their ability to read and spell correctly. After all, every word consists of letters in a specific sequence.
- Iconic memory. If a line of print were flashed at you very rapidly, say, for one-tenth of a second, all the letters you can visualise for a brief moment after that presentation constitute your iconic memory. Your iconic memory, together with your ability to discriminate between foreground and background, determines your eye-span. Eye-span is one of the skills that determine reading speed.
- Short-term memory is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. The duration of short-term memory (when rehearsal or active maintenance is prevented) is believed to be in the order of seconds.
New research on dyslexia supports the hypothesis that dyslexia is caused by memory-related deficits. Researchers studied 52 musicians, including 24 who are dyslexic and 28 who are not dyslexic, and compared the performance of the two groups in a variety of auditory tests. While the dyslexic musicians performed just as well as their non-dyslexic peers in auditory perception tests, they scored much lower on tests of auditory short-term memory.
- Long-term memory is, obviously enough, intended for storage of information over a long period of time. Despite our everyday impressions of forgetting, it seems likely that long-term memory actually decays very little over time, and can store a seemingly unlimited amount of information almost indefinitely. Indeed, there is some debate as to whether we actually ever “forget” anything at all, or whether it just becomes increasingly difficult to access or retrieve certain items from memory.
- The term working memory was coined in the 1970s by two researchers named Baddeley and Hitch, referring to the ability to temporarily hold several facts or thoughts in memory while solving a problem or performing a task.
An important and consistent finding is that working memory problems interfere with reading comprehension. Reading is a complex skill that requires the simultaneous activation of many different brain processes. When reading a word, the reader must recognise the visual configuration of letters as well as the letter order, and he must engage in segmentation (breaking the word into individual sounds). Then, while being held in working memory, the phonemes (letter sounds) must be synthesised and blended to form recognisable words.
To comprehend sentences, several more skills are necessary. The reader must not only decode the words, but also comprehend the syntax, retain the sequence of words, use contextual cues, and integrate this with existing knowledge. This must be done simultaneously in order for sentences to be understood.
At the same time, sentences must be held in working memory and integrated with one another. Each sentence is read, understood, associated and integrated with the previous one and so forth. Eventually the entire paragraph is read and the reader continues to the next one.
By the end of the chapter both the details and main idea need to be retained in working memory, otherwise the reader may have retained isolated facts but may not know the sequence of events nor understand the main idea.
Logical thinking is the process in which one uses reasoning consistently to come to a conclusion. Problems or situations that involve logical thinking call for structure, for relationships between facts, and for chains of reasoning that “make sense.”
The skill of logical thinking gives readers the ability to make inferences, which involves using what you know to make a guess about what you don't know, or reading between the lines. Readers who make inferences use the clues in the text along with their own experiences to help them figure out what is not directly said.