Dyslexia

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Dyslexia is a condition which causes difficulty with reading and writing and literally means "difficulty with the lexicon" in Greek. Today, it is thought to be a neurological disorder with biochemical and genetic markers, although there is some dispute over this claim. People are diagnosed as dyslexic when their reading problems cannot be explained by a lack of intellectual ability, inadequate instruction, or sensory problems such as poor eyesight.

Although it can be caused by brain damage (usually referred to as "Alexia" in this case), the majority of Dyslexics show no evidence of brain trauma. There are two forms of dyslexia. Developmental dyslexia appears to be present from birth, and acquired dyslexia is the result of brain trauma. It is believed that developmental dyslexia is the result of developmental differences in the brain. Many studies have shown that often there are other family members who show and have shown similar difficulties, which suggests a genetic or developmental cause of the condition. Dyslexia, as a condition, can show a pronounced difference between individuals, from being very mild to severe. It is not restricted to childhood but can continue throughout a persons life. Nor is it restricted to one sex. Male dyslexics, however, may show different symptoms from females. Native language may also affect the symptoms and severity of dyslexia.^{[[Citing sources citation needed]]}

Problems can include a persons difficulty with reading and writing, poor short-term memory for sequences, (e.g. numbers and math), and a "confused" use of their hands (for example ambidextrous people often show signs of Dyslexia). In addition, occasionally males will show a slower development of language skills in the early part of their lives. Dyslexias include the inability to name letters, to read words or sentences, or to recognize words directly even though they can be sounded out. Dyslexia is not limited to reversing the order of letters in reading or writing, as is often implied in popular culture; it may, for instance, include unexpected spelling mistakes (including phonetic spelling in English) and unusual syntax, and may be associated with dyscalculia. Most theories focus on non-primary areas in the frontal lobe and the temporal lobe. Studies have linked several forms of dyslexia to genetic markers.

The term Dyslexia was coined in 1884 by R. Berlin . Dyslexia was originally defined as a difficulty with reading and writing that could not be explained by general intelligence. One diagnostic approach is to compare their ability in areas such as reading and writing to that which would be predicted by his or her general level of intelligence. Although a variety of modern methods exist to diagnose and assist dyslexics, the causes and nature of the disease remain largely unknown.

Dyslexia International definitions.

Dyslexia is widely accepted in the international community as a specific learning disability. The most widely accepted theories argue that the dyslexic individual has biological traits that differentiate them from other individuals.

The World Health Organization (WHO)

A disorder manifested by difficulty learning to read, despite conventional instruction, adequate intelligence and sociocultural opportunity. It is dependent upon fundamental cognitive disabilities which are frequently of constitutional origin". ICD-10, The International Statistical Classification of Diseases and Related Health Problems, tenth revision ICIDH-2, The International Classification of Impairments, Activities, and Participation

US National Institute of Child Health and Human Development (NICHD) / International Dyslexia Association

Defines Dyslexia as a specific learning disability of neurological origin. Characterized with difficulties with accurate and/or fluent word recognition, spelling and decoding abilities.

Canadian Government

The Government of Canada’s Health Portal links its description to the [BC HealthGuide web site] using their definition. Dyslexia is defined here with a difficulty with the alphabet, reading, writing, and spelling in spite of normal to above average intelligence, conventional teaching, and adequate sociocultural opportunity. Dyslexia is thought to be genetic and hereditary. Dyslexia is not caused by poor vision. Dyslexia is diagnosed following psychological and educational tests that determine language and other academic abilities, IQ and problem-solving skills, and is only diagnosed if the reading disability is not a result of another condition.

The British Dyslexia Association

Dyslexia is a difference in the brain area that deals with language. It affects the underlying skills that are needed for learning to read, write and spell. Brain imaging techniques show that dyslexic people process information differently. In a report on the House of Lords Dyslexia debate which took place on Wednesday 7 December 2005 is now available the Government confirms dyslexia is not a myth.

Variations and related disorders

Dyslexia is a learning disorder. Its underlying cause may be neurological in nature, but from there, the systems involved play out into visual, language, etc. FMRI (Functional Magnetic Resonance Imaging) has been used to demonstrate differences in the dyslexic brain patterns, but much research still needs to be done to apply this information.

In addition to the typical forms of dyslexia, there are numerous related disorders:

• Auditory Processing Disorder is the cause of the phonological problems that many dyslexics experience, and causes problems in the auditory memory or working memory and auditory sequencing issues. Many with Auditory Processing issues develop visual learning coping strategies, and benefit from a Whole Language approach to reading, and using multi-colored or multi-formatted text.
• Semantic dyslexia - a form of dyslexia characterized by an inability to properly attach words to their meanings in reading and/or in speech.
• Scotopic sensitivity syndrome - a form of dyslexia which makes it very difficult for a person to read black text on white paper, particularly when the paper is slightly shiny. Contrary to how it seems to be defined, this is not an optical problem. It is a problem with how the nervous system encodes and decodes visual information. For many dyslexics color overlays which are matte on onside and glossy on the other help reduce the glare on the paper and reduce the scotopic effects. Some dyslexics wear glasses which have a color tint to them which also help with the condition. In the scientific community the uses and why these filters work is debated.
• Dyspraxia - a neurological disorder characterized by a marked difficulty in carrying out routine tasks involving balance, fine-motor control, and kinesthetic coordination. Which is most common in dyslexics who also have an attention deficit disorder.
• Verbal Dyspraxia - a neurological disorder characterized by marked difficulty in the use of speech sounds, which is the result of an immaturity in the speech production area of the brain.
• Dysgraphia - a neurological disorder characterized by distorted and incorrect handwriting.
• Dyscalculia - a neurological disorder characterized by a problem with learning fundamentals and one or more of the basic numerical skills. Often people with this disorder can understand very complex mathematical concepts and principles but have difficulty processing formulas and even basic addition and subtraction.

Facts and statistics

Between 5 and 15 percent of the population can be diagnosed as suffering from various degrees of dyslexia. As previously mentioned, dyslexia can be substantially compensated for with proper therapy, training and equipment.

Most researchers agree that there is a fairly even gender balance amongst dyslexics, and that the fact that it is reported more in males is because of selection factors and bias.

Dyslexia's main manifestation is a difficulty in developing reading skills in elementary school children. Those difficulties result from reduced ability to associate visual symbols with verbal sounds. While motivational factors must also be reviewed in assessing poor performance, dyslexia is considered to be an inborn trait and rarely arises from environmental factors after the brain has matured beyond its especially plastic condition during infancy.

About half of all dyslexics also have an attention deficit disorder (ADD or ADHD). The combination of dyslexia and an attention deficit disorder is also known as DAMP or deficit attention motor perception.

Physiology and treatment

Only traditional educational remedial techniques have any record of improving the reading ability of those diagnosed with dyslexia . There is no evidence that colored lenses, any visual training, or similar proposed treatments are of any use. Anecdotal reports of success can be explained by other factors.

Even a few weeks of intense phonological training (often involving breaking down and rearranging sounds to produce different words) can help noticeably improve reading skills. The earlier the phonological regimen is taken on, the better the overall result. Advanced brain scans could identify children at risk of dyslexia before they can even read, although it is thought that simple tests of balance could do the same. It is claimed that many of the underlying causes of dyslexia are of a genetic nature and that there are no cures, only strategies to work around the causes of a person's dyslexia, however these two claims are disputed.

It had been believed that keeping a child active, perhaps by giving them housework, or performing physical exercises, would help with dyslexia. However, this is false . There is no scientific evidence in support of this theory.

Researchers studying the brains of dyslexics have found that during reading tasks, dyslexics show reduced activity in the left inferior parietal cortex. It is anecdotally claimed that it is not that uncommon for dyslexics who have trained themselves to cope with their affliction, to develop uncannily efficient visual memories which aid in reading and comprehending large quantities of information much faster than is typical. Commonly dyslexics show 10 times more brain activity when reading. Sometimes, depending of the type and extent, also writing, listening and speaking. However, increased brain activity is not necessarily a sign of better processing. Conversely, some dyslexics may show a natural dislike of reading and, in consequence, compensate by developing unique verbal communication skills, inter-personal expertise, visual-spatial abilities and leadership skills.

In 1979, anatomical differences in the brain of a young dyslexic were documented. Albert Galaburda of Harvard Medical School noticed that the language center in a dyslexic brain showed microscopic flaws known as ectopias and microgyria. Both affect the normal six-layer structure of the cortex. An ectopia is a collection of neurons that have pushed up from lower cortical layers into the outermost one. A microgyrus is an area of cortex that includes only four layers instead of six.

These flaws affect connectivity and functionality of the cortex in critical areas related to auditory processing and visual processing. These and similar structural abnormalities may be the basis of the inevitable and hard to overcome difficulty in reading.

Another study regarding genetic regions on chromosomes 1 and 6 have been found that might be linked to dyslexia. Presenting the argument, dyslexia is a conglomeration of disorders that all affect similar and associated areas of the cortex.

Some studies have concluded that speakers of languages whose orthography has a strong correspondence between letter and sound (e.g. Korean and Italian) have a much lower incidence of dyslexia than speakers of languages where the letter is less closely linked to the sound (e.g. English and French).

Characteristics

Ronald D. Davis places forth the argument that most dyslexics will exhibit about 10 of the following traits and behaviors. These characteristics can vary from day-to-day or minute-to-minute. The most consistent thing about dyslexics is their inconsistency. Symptoms increase dramatically with confusion, time pressure, emotional stress, or poor health. This may vary according to which of the suggested underlying causes of dyslexia affect the individual dyslexic.

General

• Appears bright, highly intelligent, and articulate but unable to read, write, or spell at grade level.
• High in IQ, yet may not test well academically; tests well orally, but not written.
• Labelled lazy, dumb, careless, immature, "not trying hard enough," or "behavior problem."
• Isn't "behind enough" or "bad enough" to be helped in the school setting.
• Feels dumb; has poor self-esteem; hides or covers up weaknesses with ingenious compensatory *strategies; easily frustrated and emotional about school reading or testing.
• Learns best through hands-on experience, demonstrations, experimentation, observation, and visual aids.
• Talented in art, drama, music, sports, mechanics, story-telling, sales, business, designing, building, or engineering.
• Seems to "Zone out" or daydream often; gets lost easily or loses track of time.
• Difficulty sustaining attention; seems "hyper" or "daydreamer."

Vision, reading, and spelling

There is no scientific evidence that a relationship exists between reading failure and perceptual ability or that visual training provides effective treatment.

• Dyslexics may have Irlen Syndrome - simply explained - the glare of the white page against black letters causes the words to shake, shiver, spin, etc. after a few minutes of reading. The treatment is testing and the use of colored plastic overlays that help anchor the words to the page.
• Spelling - Dyslexics appear to be unable to hear vowel sounds. Magic is spelled mjc.
• Reading - Due to dyslexics' excellent long term memory, young students tend to memorize beginning readers, but are unable to read individual words or phrases.

Hearing and speech

• Has extended hearing; hears things not said or apparent to others; easily distracted by sounds.
• Difficulty putting thoughts into words; speaks in halting phrases; leaves sentences incomplete; stutters under stress; mispronounces long words, or transposes phrases, words, and syllables when speaking.
• Dyslexics are auditory learners

Writing and motor skills

• Trouble with writing or copying; pencil grip is unusual; handwriting varies or is illegible.
• Clumsy, uncoordinated, poor at ball or team sports; difficulties with fine and/or gross motor skills and tasks; prone to motion-sickness.
• Can be ambidextrous, and often confuses left/right, over/under.
• May write in "mirror writing" (writing that appears backwards, but can be read when reflected in a mirror)
• Dyslexics tend to "draw" letters and numbers and take a long time before any automaticity is achieved.

Math and time management

• Has difficulty telling time, managing time, learning sequenced information or tasks, or being on time.
• Shows dependence on finger counting and other tricks when doing math; knows answers, but can't do it on paper.
• Can count, but has difficulty counting objects and dealing with money.
• Can do arithmetic, but fails word problems; when doing math must see the big picture before the detail.
• Dyslexics can be gifted in math while poor in reading and cognative skills.

Memory and cognition

• Excellent long-term memory for experiences, dates, names, locations, and faces.
• Poor memory for sequences, facts and information that have not been experienced.
• Thinks primarily with images and feeling, not sounds or words (little internal dialogue).
• Poor short-term memory - forgets things easily, particularly when a sequence of actions is required.

Behavior, health, development and personality

• Extremely disorderly or compulsively orderly.
• Can be class clown, trouble-maker, or too quiet.
• Had unusually early or late developmental stages (talking, crawling, walking, tying shoes).
• Prone to ear infections; sensitive to foods, additives, and chemical products.
• Extremely sensitive to human contact- when another person touches them they may feel very "uncomfortable."
• Can be an extra deep or light sleeper; bed wetting beyond appropriate age.
• Unusually high or low tolerance for pain.
• Strong sense of justice; emotionally sensitive; strives for perfection.
• Similar to other learning challenged people, dyslexics lag an average of two years behind their peers in emotional and social development.

Public support

In the United States, Canada, New Zealand and in the United Kingdom, some people say that there is a lack of adequate support and a general lack of interest in the learning disabilities of children in public schools. This has recently led to legal action by private parties against public schools in the United States and state schools in the United Kingdom. In English law, the recent case of Skipper v Calderdale Metropolitan Borough School (2006) EWCA Civ 238 the Court of Appeal applied Phelps v London Borough of Hillingdon (2001) 2 AC 619 as the landmark case on the failure to diagnose dyslexia (see duty of care in English law), and to hold that the appellant could pursue her claim against her school for humiliation, lost confidence, and lost self-esteem, and for loss of earnings following its failing to diagnose and treat her dyslexia despite the fact that, as Latham LJ. says at para 29:

"The extent to which her dyslexia could have been ameliorated or provided for will always remain uncertain, as will the extent to which that would have affected her performance in public examinations; the evidence that we have includes material to suggest that she, not surprisingly, reacted adversely to the break-up of her parents marriage when she was 15, in other words at a critical time in her education. Whether any improvement in her examination results would have led to her life taking a significantly different course will also be a matter for some speculation."

Some charitable organizations like the Scottish Rite Foundation have undertaken the task of testing for dyslexia and making training classes and materials available, often without cost, for teachers and students.

In England and Wales, the failure of schools to diagnose and provide remedial help for dyslexia following the House of Lords decision in the case of Pamela Phelps has created an entitlement in students with dyslexia in Higher Education to receive support funded via the Disabled Students Allowance. Support can take the form of IT equipment (software and hardware) as well as personal assistance, also known as non-medical helper support. Dyslexic students will also be entitled to special provision in examinations such as additional time to allow them to read and comprehend exam questions.

The British Disability Discrimination Act also covers dyslexia.

"In some cases, people have 'coping strategies' which cease to work in certain circumstances (for example, where someone who stutters or has dyslexia is placed under stress). If it is possible that a person's ability to manage the effects of the impairment will break down so that these effects will sometimes occur, this possibility must be taken into account when assessing the effects of the impairment." — Paragraph A8, Guidance to the Definitions of Disability

Many doctors and teachers diagnose students with Attention Deficit Disorder rather than dyslexia. Of all the conditions that can mimic, mask or co-exist with ADD, dyslexia is probably the most well known. It is also one of the most misunderstood. Dyslexia is a different learning style that affects 17-20% of school age children according to the Department of Health, Education and Welfare. Like ADD, the dyslexic mind functions differently than others. Dyslexic children, like ADD children, tend to have specific difficulties with words. They have difficulty recalling words, even words they are familiar with. They also have difficulty with sequencing. Letters and syllables can become inverted (like "aminal") as can entire words. ("Come here over.") The child may have trouble distinguishing between the letters "b," "d," "q" and "p."

Controversy

"The Dyslexia Myth" is a documentary that appeared as part of the Dispatches series produced by British broadcaster Channel 4. First aired in September 2005, it claims to expose myths and misconceptions that surround dyslexia. It argues that the common understanding of dyslexia is not only false but makes it more difficult to provide the reading help that hundreds of thousands of children desperately need. Drawing on years of intensive academic research on both sides of the Atlantic, it challenged the existence of dyslexia as a separate condition, and highlighted the many different forms of reading style.

Critics claim that through FMRI it has been demonstrated that the dyslexic mind processes information - mostly in pictures, sounds and emotion - about 1300 to 25000 times faster than the 'normal' brain, which is considered to work with verbal thought processes. The 'normal' person is limited to the speed of speech, as opposed to the dyslexic who thinks mainly in non-verbal terms. This means that much information is lost when trying to put thoughts into words, as to the dyslexic the process can feel similar to translating a foreign language.

References

See also

• International Dyslexia Association
• Picture thinking
• Double deficit
• List of people with dyslexia
• Alexia (disorder)
• Educational psychology
• Asfedia
• Landmark East School

External links

• [International Dyslexia Association (IDA)]
• [Help for Parents of Dyslexic Children]
• [Neuron Learning Fast ForWord]
• [Achieve Publications] Offers solutions for children and adults with learning disabilities or dysylexia
• [LD Support] Offers answers to FAQs for learning disabled and gifted students
• [ReadingDoctor Software] Literacy Development Software for dyslexic children made by a specialist Speech-Language Pathologist

Regional associations and organizations

• [Auditory Processing Disorder (UK)]
• [British Dyslexia Association]
• [Canadian Dyslexia Association]
• [Davis Dyslexia Association International (DDAI)]
• [Danks Davis Dyslexia]
• [Dyslexia Council (UK)]

 

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