April 27, 2011

Dyslexia

Developmental reading disorder, also called dyslexia, is a reading disability that occurs when the brain does not properly recognize and process certain symbols. It is caused by impairment in the brain's ability to translate images received from the eyes or ears into understandable language. It does not result from vision or hearing problems.  

Different types of dyslexia

There are several types of dyslexia that can affect the child's ability to spell as well as read.

"Trauma dyslexia" usually occurs after some form of brain trauma or injury to the area of the brain that controls reading and writing. It is rarely seen in today's school-age population.

A second type of dyslexia is referred to as "primary dyslexia." This type of dyslexia is a dysfunction of, rather than damage to, the left side of the brain and does not change with age. Individuals with this type are rarely able to read above a fourth-grade level and may struggle with reading, spelling, and writing as adults. Primary dyslexia is passed in family lines through their genes (hereditary). It is found more often in boys than in girls.

A third type of dyslexia is referred to as "secondary" or "developmental dyslexia" and is felt to be caused by hormonal development during the early stages of foetal development. Developmental dyslexia diminishes as the child matures. It is also more common in boys.

Dyslexia may affect several different functions. Visual dyslexia is characterized by number and letter reversals and the inability to write symbols in the correct sequence. Auditory dyslexia involves difficulty with sounds of letters or groups of letters. The sounds are perceived as jumbled or not heard correctly.

Symptoms

The symptoms of dyslexia vary according to the severity of the disorder as well as the age of the individual.

Preschool-aged children

It is difficult to obtain a certain diagnosis of dyslexia before a child begins school, but many dyslexic individuals have a history of difficulties that began well before kindergarten. Children who exhibit these symptoms early in life have a higher likelihood of being diagnosed as dyslexic than other children. 

These symptoms include:

Delays in speech

Slow learning of new words

Difficulty in rhyming words, as in nursery rhymes

Low letter knowledge

Letter reversal or mirror writing (for example, "Я" instead of "R")

Early primary school children

Difficulty learning the alphabet or letters order

Difficulty with associating sounds with the letters that represent them (sound-
symbol correspondence)

Difficulty identifying or generating rhyming words, or counting syllables in words (phonological awareness)

Difficulty segmenting words into individual sounds, or blending sounds to make words (phonemic awareness)

Difficulty with word retrieval or naming problems

Difficulty learning to decode written words

Difficulty distinguishing between similar sounds in words; mixing up sounds in polysyllabic words (auditory discrimination) (for example, "aminal" for animal, 
"bisghetti" for spaghetti)

Older primary school children

Slow or inaccurate reading (although these individuals can read to an extent).

Very poor spelling 

Difficulty reading out loud, reading words in the wrong order, skipping words and sometimes saying a word similar to another word (auditory processing disorder)

Difficulty associating individual words with their correct meanings

Difficulty with time keeping and concept of time when doing a certain task

Difficulty with organization skills (working memory)

Children with dyslexia may fail to see (and occasionally to hear) similarities and differences in letters and words, may not recognize the spacing that organizes letters into separate words, and may be unable to sound out the pronunciation of an unfamiliar word (auditory processing disorder).

In general, symptoms of DRD may include:

Difficulty determining the meaning (idea content) of a simple sentence

Difficulty learning to recognize written words

Difficulty rhyming

DRD may occur in combination with writing or math learning problems.

How is dyslexia diagnosed?

Dyslexia is a difficult disorder to diagnose. There are many factors the psychologist or other health professional reviews to diagnose the disability. The testing determines the child's functional reading level and compares it to reading potential, which is evaluated by an intelligence test. All aspects of the reading process are examined to pinpoint where the breakdown is occurring. The testing further assesses how a child takes in and processes information and what the child does with the information. The tests determine whether a child learns better by hearing information (auditory), looking at information (visual), or doing something (kinesthetic). They also assess whether a child performs better when allowed to give information (output), by saying something (oral), or by doing something with their hands (tactile-kinesthetic). The tests also evaluate how all of these sensory systems (modalities) work in conjunction with each other.

A standard battery of tests can include, but is not limited to, the following:

Wechsler Intelligence Scale for Children-Third Edition (WISC-III)

Kaufman Assessment Battery for Children (KABC)

Stanford-Binet Intelligence Scale

Woodcock-Johnson Psycho-Educational Battery

Peabody Individual Achievement Tests-Revised (PIAT)

Test of Auditory Perception (TAPS)

Test of Visual Perception (TVPS)

Expressive One-Word Picture Vocabulary Test

Test for Auditory Comprehension of Language

Treatment

Every person with DRD requires a different strategy. An individual education plan should be created for each child with the condition.

The following may be recommended:

Extra learning assistance, called remedial instruction

Private, individual tutoring

Special day classes

Positive reinforcement is important as many students with learning disabilities have poor self-esteem.

Psychological counselling may be helpful.

No comments:

Post a Comment