This article on How to Diagnose Dyslexia will discuss the definition of dyslexia, the various types of dyslexia, the signs and warnings, and testing used to diagnose dyslexia.

The World Federation of Neurologists have defined dyslexia as “a disorder in children who, despite conventional classroom experience, fail to attain the language skills of reading, writing, and spelling commensurate with their intellectual abilities”. It is the most common learning disability in children and continues for their entire lives. Early treatment is important in children to improve their language skills. Even older individuals can benefit from treatment and show improvement in their language skills.http://www.medicinenet.com/dyslexia/article.htm

Dyslexia is caused by impairment in the ability of the brain to interpret images that are seen by the eyes or heard by the ears, into a language that is comprehensive. Even children who have the opportunity to receive good traditional learning and have average intelligence still have problems learning to read. This does not result from lack of intelligence, hearing or vision problems, brain damage, or mental retardation.http://www.medicinenet.com/dyslexia/article.htm

In many cases, children with dyslexia have problems in school and appear to be unmotivated and dislike school. They may also appear to be depressed, have low self-esteem, and have behavior problems both at home and at school. Dyslexia is often undetected and disguised by these appearances. If these children are not treated, they only become more frustrated by the difficulties they are experiencing with their language skills, which can increase their other problems.http://www.medicinenet.com/dyslexia/article.htm

Causes:

The major cause for dyslexia is both neurobiological and genetic. The genetic links for dyslexia are inherited. A child with dyslexia most likely has a parent, grandparent, aunt, or uncle that is dyslexic.http://www.depression-guide.com/dyslexia.htm

Dyslexia affects children who are academically capable, have good home environments, and are emotionally and physically healthy. Many children with dyslexia have high mental ability, attend good schools, and have well educated parents who value learning. While it is difficult to estimate how prevalent dyslexia is, it is felt approximately 15% of students could be classified as dyslexic.http://www.healthscout.com/ency/68/267/main.html

Categories of Dyslexia:

There are three major categories of dyslexia that affect a child’s ability to read and spell, including:

1. Traumatic dyslexia which may occur when a trauma or injury has happened to the area of the brain that controls writing and reading. This is not seen often in school-age population of today.
2. Primary dyslexia which is a dysfunction of the left side of the cerebral cortex and does not change with age. This is not caused by any damage to the brain. Individuals with primary dyslexia are seldom able to read at about a fourth grade level. As adults, they may struggle with spelling, writing and reading. This type of dyslexia is hereditary and is passed in family lines through their genes. It is occurs more often in boys than girls.
3. Secondary (developmental) dyslexia which occurs during the early stages of the development of the fetus and is caused by hormonal development. This type of dyslexia is more common in boys and lessens as the child ages.http://www.understanding-learning-disabilities.com/types-of-dyslexia.html

Dyslexia affects approximately 10% of the population (4% severely).http://www.depression-guide.com/dyslexia.htm

There is a huge spectrum of types of dyslexia and varying degrees of severity, such as:

1. Literal dyslexia is also called letter blindness where the person has difficulty naming letters, matching sounds with the letters, and matching uppercase and lowercase letters.
2. Word dyslexia is where the individuals may read the letters of the word but not the word itself, or not understand the meaning of the word. Sometimes tracing the outline of the word or tracing the letters in the air helps them do better.
3. Phonological dyslexia is where the individual has difficulty converting letters to sounds. They can read familiar words but may not be able to read novel or unfamiliar words.
4. Neglect dyslexia causes the individual to neglect either the beginning or the end of words. In words such as cowboy, the individual may read either cow or boy. The longer the word, the more difficulty they have.
5. In Semantic dyslexia the meaning of the word gets distorted because it is read incorrectly or the individual is confused about the meaning of a word. The person may say cat or fox when reading the word dog, or they may say shopped instead of shop.
6. Spelling dyslexia which causes individuals to have problems reading all types of words and may have trouble identifying individual letters. They read slowly and hesitantly, especially if the word is long. They may even read words one letter at a time even if they are familiar with the word.
7. Pure dyslexia (dyslexia without dysgraphia) is where the person has a problem reading but not writing. Sometimes it is never identified because the person may speak just fine and their writing and oral spelling may be unimpaired.
8. Deep dyslexia (dyslexia with dysgraphia) is where the individual has trouble with writing words and letters, getting the meanings of words, integrating the letter sounds, and in pronouncing familiar, as well as unfamiliar, words. These individuals face the biggest challenge and need the most attention in planning their education and careers.http://www.mindpub.com/art169.htm
9. Visual dyslexia (visual processing disorder) happens as a result of the immature development of the eyes and the process that gets the information from the eyes to the brain. This causes poor comprehension and results in reversals of numbers and letters, and an inability to write symbols in a sequence that is correct.
10. Phonological (auditory) dyslexia is a learning disability called auditory processing. It is also called Auditory Processing Disorder (OPD) when it is severe. This form of dyslexia causes received sounds to be jumbled or not heard properly.
11. Dyspraxia is a learning disability characterized by impairment of movement organization, with additional problems with perception, thought, and language. The child appears to be clumsy and lacks coordination. There are two types, true dyspraxia and developmental dyspraxia. True dyspraxia is a lifelong condition that can be helped somewhat by early, structured intervention. Developmental dyspraxia is a neurological immaturity that can be resolved over time with the proper treatment.
12. Verbal praxis is the inhibition of expressive language and the impairment of articulation. This is not considered a learning disability and is treated by speech and language therapy.
13. Dysgraphia is considered an immaturity in fine motor development where the individual is unable to control or hold a pencil to print or write cursive.
14. Dyscalculia, while lesser known, is related to dyslexia and developmental dyspraxia. It involves impairment in the ability to solve math problems, which ordinarily results from brain dysfunction.http://www.understanding-learning-disabilities.com/types-of-dyslexia.html

While teachers may not be able to determine whether a child has dyslexia, they may be able to detect early signs and refer the child for further assessment by a psychologist or health professional. Children often reverse their letters and numbers until they are 7 or 8, but if it does not diminish after that, it is a common warning sign that the child may have dyslexia. Another sign may be difficulty-copying material from the blackboard or a book. Their written work may be disorganized. Not remembering content of a favorite video or storybook is another telltale sign.

On the playground the teacher may notice that the child is uncoordinated and has problems with organized sports or games. They may have problems with right and left, and their dominant hand may not be established. The child with dyslexia may also have problems with moving to music rhythms.

Children with dyslexia may have trouble remembering what they hear or sequences of things. They may be unable to respond to more than one command at a time. Parts of sentences or words may be missed. Wrong or similar words may be used instead of the correct ones. They may know what they want to say but cannot find the correct words to say it.

Children with dyslexia may appear to be depressed because they have become withdrawn. They may act out to cover up for their difficulty with learning. They may lose interest in school activities and appear to be lazy or unmotivated. They may have problems with self-esteem and strained interactions with their siblings. These emotional issues require just as much attention as the learning issues.http://www.medicinenet.com/dyslexia/page2.htm

More specific symptoms will be discussed in the article on How to Treat Dyslexia.

Diagnosis:

The first step in diagnosing dyslexia is getting a medical history from the individual and performing a complete physical examination and eye examination. This will rule out other possible causes of reading difficulties. A physician will obtain a medical history and perform a physical exam in order to rule out other causes of reading difficulty, including vision problems. Testing by a psychologist is often recommended.

Testing can be stressful for children, especially when they are already concerned with their school performance, so alternative strategies are tried first. After an assessment plan has been determined, it is discussed with the child’s parent(s) to get permission to perform the testing. The assessment plan is created based on the specific problems the child has. It should include testing in five different areas, such as: intelligence (cognition), academic performance, communication, sensory and motor, and health and developmental. After the child is tested, the school team meets with the parent(s) and discusses the results of the tests and the specific type of dyslexia the child may have.http://www.medicinenet.com/dyslexia/page3.htm

Some of the specific things this battery of tests determines are:

1. the child’s functional reading level and where the breakdown is happening;
2. how the child receives and processes information, and what they do with the information;
3. whether the child learns better by hearing information, visualizing information, or by doing it (kinesthetic); and
4. whether the child performs better when giving information, by saying something, or by doing something with their hands.

Before testing, the child should get a good night’s rest and eat a good breakfast. They should be reassured that there is nothing wrong because they are being tested. If possible, they should meet the person giving the tests beforehand. The parents should not be present when the child is being tested.

Testing Options:

1. Wechsler Intelligence Scale for Children-Third Edition (WISC-III)
2. Kaufman Assessment Battery for Children (KABC)
3. Stanford-Binet Intelligence Scale
4. Woodcock-Johnson Psycho-Educational Battery
5. Peabody Individual Achievement Tests-Revised (PIAT)
6. Wechsler Individual Achievement Tests (WIAT)
7. Kaufman Tests of Educational Achievement (KTEA)
8. Bender Gestalt Test of Visual Motor Perception
9. Beery Developmental Test of Visual-Motor Integration
10. Motor-Free Visual Perception Test
11. Visual Aural Digit Span Test (VADS)
12. Test of Auditory Perception (TAPS)
13. Test of Visual Perception (TVPS)
14. Peabody Picture Vocabulary Test-Revised
15. Expressive One-Word Picture Vocabulary Test
16. Test for Auditory Comprehension of Languagehttp://www.medicinenet.com/dyslexia/page4.htm/ref

The content on this page is for information purposes only and is not a substitute for professional medical advice. Speak with a qualified heath care professional to ensure that you have the most accurate information regarding any medical diagnosis.