Developmental Dyslexia: An Overview

from School Health Reporter, Spring 2003

Dyslexia is a language-based learning disability. An individual with dyslexia may have difficulty reading, spelling, understanding spoken language and expressing thoughts and ideas clearly when speaking or writing.  However, the core difficulty for most people with dyslexia is in the ability to make rapid and accurate associations between speech sounds and the letter or letters used to represent those sounds.

Many people commonly tend to understand dyslexia as a condition in which such letters as b and d are reversed and words are read backwards, such as was for saw. This understanding of dyslexia is based on superficial observation however, and is not grounded in science. In fact, the primary characteristic of dyslexia is a specific problem in processing sounds within words and breaking the sound-symbol code of language. It is important to be aware that results of well-founded scientific research indicate that only in very rare cases are dyslexic difficulties related to problems with vision.  People with dyslexia have difficulty recognizing, manipulating and learning the speech sounds (phonemes) that correspond to letters in our alphabet – a skill called “phonological processing.”

As a result, learning to read and spell becomes a significant challenge.  In addition, children with dyslexia often experience difficulty with a wide variety of other language-related tasks. Common symptoms include:

• Difficulty learning the sounds that go with letters
• Labored and effortful word recognition and identification (both in isolation and in context)
• Word retrieval problems
• Incorrect pronunciations (“tesacope” for stethoscope)
• Difficulty forming letters
• Poor ability to remember spellings of words that may have been adequately memorized to pass the Friday morning test
• Trouble memorizing math facts
• Poor ability to simultaneously process word choice, sentence structure, mechanics of punctuation and capitalization, and spelling when writing
• Difficulty learning a foreign language

Evidence-based scientific research has also provided other important data about dyslexia during the last two decades. We know that the reading problems most characteristic of dyslexia affect approximately 20 percent of children learning to read, and that girls and boys are equally affected. Researchers (including a team headed by Dr. Bruce Pennington at the University of Denver ) have established that dyslexia runs in families.  They also have identified the genes and chromosomes that appear to carry dyslexia as a heritable trait.

We know that early signs of reading difficulty should not be ignored, or attributed to immaturity or developmental delay. A 1988 study by Connie Juel, reported in the Journal of Educational Psychology, found that nine out of ten children with deficient reading skills in first grade were poor readers in fourth grade. And a 1996 study by D.J. Francis, et. al., reported in the same journal, concluded that 74 percent of poor readers in third grade remained poor readers in ninth grade.

Diagnosis

Developmental dyslexia is generally considered to be a clinical and/or medical diagnosis. It can be accurately diagnosed by a competent learning specialist, speech-language pathologist or clinical psychologist with training in language and learning disabilities.  There is no one specific “test” for dyslexia. Insurance companies differ in their willingness to pay for such independent evaluations. Those companies who provide such a benefit recognize the evaluation as a clinical assessment of cognitive, behavioral, perceptual, attentional and processing difficulties beyond the scope of typical school-based assessments. Other companies persist in believing that reading problems are exclusively educational concerns that can be adequately diagnosed in school settings.

Dyslexia, as a diagnostic term, is often not used in school-based assessments and reports, although the common symptoms and characteristics of dyslexia are generally similar, or identical to, the problems that make children eligible for special education support under the category of “perceptual/communicative disorders.”  Children who qualify in this category have processing and learning disability features, and would often be diagnosed as dyslexic if evaluated in a clinical setting.

More problematic for parents and educators however, are the children who do not qualify for special education services, in spite of reading, spelling and language difficulties which are easily observed by parents and classroom teachers. These are the children who clearly struggle with many classroom and homework requirements, but who perform adequately on the measures of basic academic skills that are commonly used in school-based assessments.

It is extremely important for parents and teachers to understand that mfailure to qualify for special education services does not necessarily mean that a child has no learning disability or dyslexic features. In these cases, additional independent testing is often necessary to provide a more in-depth assessment of such processing features as phonological awareness, nonsense word decoding, reading and retrieval fluency, cognitive efficiency, processing speed and rapid naming speed, which are indicative of dyslexia.

Treatment

Reading experts have concluded that approximately one-third of children can learn to read regardless of approach, because they have a strong, innate ability to link speech sounds to letters and to make implicit associations between speech and print. Many children however, lack this ability to intuitively figure out phonics and to teach themselves new sound/letter patterns as they are encountered.

Twenty years of scientific research on the components of effective classroom reading instruction are presented clearly in the 2000 report from the National Reading Panel (see References). These findings pertain to regular classroom instruction, but it is striking that their recommendations are highly consistent with the methods that have long been advocated by learning disability specialists and such organizations as the International Dyslexia Association.

The conclusions drawn are that effective reading instruction for all students, including those with dyslexia, is based upon principles of multi-sensory, structured language.  Effective classroom or tutorial practices include:

• Direct teaching of phonemic awareness, including segmentation and blending, so that children develop automatic ability to identify and remember speech sounds and to represent them correctly with letters
• Systematic, direct teaching of phonics and sounding-out strategies to read unknown words
• Explicit instruction in English syllable types and syllabic analysis for decoding
• Reading practice using “decodable” texts
• Deliberate development of reading fluency, with an emphasis on guided and repeated oral reading, rather than independent silent reading
• Direct instruction in English word origins and etymologies, roots, prefixes and suffixes
• Vocabulary instruction with an emphasis on definitions and use in context before, during and after reading
• Direct teaching of such comprehension strategies as summaries, diagrams, visual representations, literal and inferential reasoning

There are many multi-sensory structured language approaches. These approaches vary according to whether they are designed for classroom or individual instruction, and whether the students are in early, middle or later grades. They are all largely variations on the Orton-Gillingham approach and are widely used by schools, clinics and private practitioners.  Outcomes of recent research also have compelled a number of major reading textbook publishers to revise and improve their products to include direct, systematic, multi-sensory instruction components in regular classroom reading instruction.

If you have additional questions or concerns about a student who demonstrates features of dyslexia, please call (720) 777-6806, or send an e-mail to puls.meredith@tchden.org .