Dyslexia is a learning disability related to reading and writing that is neurological in origin. It is the most common learning disorder among children of school age.
Dyslexia is not a single condition but rather a cluster of symptoms related to reading difficulties and other language skills. Children with dyslexia usually have problems pronouncing words and spelling them correctly as well as difficulties with writing words and sentences. Most people with dyslexia have trouble identifying the separate speech sounds within a word or learning how letters represent those sounds. This particular language skill is known as decoding. Although there is a popular belief that dyslexia is a visual problem that involves reading letters or words backward or upside down, this belief is not true. Reversals of letters or words are also not a defining characteristic of dyslexia.
Dyslexia is not associated with mental retardation; it can affect children at all levels of intelligence. Most children with dyslexia are of normal intelligence; some are highly gifted, and many excel in fields that do not require high-level language skills, including the visual arts, computer science, design, drama, electronics, math, mechanics, music, physics, dance, and athletic competition.
Dyslexia does not affect all children equally. Some children diagnosed with the condition are able to master the basics of reading and
spelling, particularly if they have competent and dedicated teachers. They may, however, run into difficulty when they reach the upper grades and are confronted with the need for more complex language skills that include a knowledge of grammar, the ability to read and remember textbook material, and the ability to write longer compositions.
Some children with dyslexia have problems with understanding spoken language even though they have teachers and parents with good spoken language skills. These children may have trouble expressing themselves or may misunderstand what others say. Problems with spoken language place this group of dyslexics at a severe disadvantage not only in school and later on in the workplace but also in their relationships with other people.
Dyslexia is thought to affect about five out of every 100 school-age children in the United States, with another 5–10 percent having difficulty with reading. Some researchers think that as many as 20 percent of American adults have some of the symptoms of dyslexia, including slow or inaccurate reading, problems with spelling and writing, or mixing up words that sound similar.
At one time it was thought that boys were more likely to be dyslexic than girls; however, researchers now think that boys and girls are equally likely to have the disorder.
The causes of dyslexia are not completely understood but are thought to be related to differences in the structure and functioning of the brain. Dyslexics appear to process information in a different part of the brain than nondyslexics. Although the condition has not yet been conclusively traced to specific genes, it is known to run in families. In 2005, researchers identified a region on chromosome 6 as possibly related to dyslexia, but this finding has not yet been verified.
The Fonz Becomes a Writer
Henry Winkler (1945–), the actor who played the Fonz in the long-running television show Happy Days, had a miserable childhood because of undiagnosed dyslexia. He recalls that lunch was the only subject he was good at doing. Even his parents thought he was dumb and lazy. Winkler eventually finished his education, including a master's degree from the Yale School of Drama, and went on to become a well-regarded actor but still has painful memories of his early years. He was finally diagnosed with dyslexia at the age of thirty-one, when his stepson was also diagnosed with the disorder.
Winkler decided to make a career change and help children who have trouble with language skills. He has produced a series of books together with a writer named Lin Oliver about a boy named Hank Zipzer, “The World's Greatest Underachiever.” The books follow Hank's adventures at Winkler's old school, P.S. 87 in New York City. Winkler told an interviewer in 2007 that he tries to make the books as good-humored as possible to encourage young readers. He was delighted by a letter he received recently
from a boy in Montana who said, “I laughed so hard, my funny bone fell out of my body.”
One surprising finding, reported by a team of researchers at Hong Kong University in 2008, is that the part of the brain affected by dyslexia appears to differ according to the child's primary language. The researchers used magnetic resonance imaging (MRI) to compare a group
of children whose first language is English with a second group raised to speak Chinese. The scientists found that the English speakers use a different part of the brain when reading from that used by the Chinese students. The difference is apparently related to the fact that English is an alphabetic language whereas Chinese uses symbols to represent words.
In addition to having trouble associating letters with sounds and forming memories for words, children with dyslexia may have some of the following problems with learning:
- Learning to speak.
- Organizing thoughts and ideas into clear written and spoken language.
- Memorizing number facts, such as the multiplication tables.
- Reading quickly enough to understand what is being read. Some children with dyslexia read so slowly that they cannot remember the beginning of a sentence by the time they reach the end of it, particularly if it is a long and complicated sentence.
- Making their way through longer reading assignments.
- Spelling words correctly.
- Trouble with making rhymes.
- Learning foreign languages, which involves a basic understanding of grammar and the parts of speech.
- Performing mathematical calculations correctly.
The diagnosis of dyslexia can be a complicated process that usually involves a psychologist and an education expert as well as the child's family doctor. The first step is to rule out any disorders of vision or hearing that could interfere with learning. The child may also be referred to a neurologist (a specialist in disorders of the nervous system) for further evaluation to make sure that the child does not have a brain tumor or other physical disease of the brain.
The next step is usually intelligence testing and an evaluation of the child's reading and speaking skills by a qualified expert. This type of evaluation involves testing the child's short-term memory or asking the child to read nonsense words as a test of his or her ability to link letters and sounds. In addition, the child may be evaluated psychologically to see whether depression, anxiety, or social problems are causing the learning difficulty.
There is no medical or surgical cure for dyslexia; however, dyslexic individuals can learn to read and write with appropriate education or treatment. Treatment for dyslexia is highly individualized. After the child's specific difficulties in reading and understanding language have been analyzed by an expert, a treatment program is drawn up tailored to his or her needs. Most children with dyslexia benefit from a multisensory approach to language. A multisensory approach is one that involves several senses (seeing, hearing, touching) all at the same time. Teachers who use this approach teach children to link the sounds of the letters with the written symbol. Children also link the sound and symbol with how it feels to form the letter or letters. Another way to use the multisensory approach is to have the child listen to an audiotape while tracing the shapes of letters with the fingers and the words spoken.
Children with severe dyslexia may require tutoring on a one-to-one basis or in small group sessions several times a week. Whereas a child with normal language skills may need sixty to ninety hours to master a specific set of tasks involving reading, children with dyslexia may need between eighty and 100 hours to make the same progress. In general, the earlier a child is diagnosed and special education programs are started, the greater the likelihood that he or she will learn to read well enough to succeed in school. Some children with severe dyslexia, however, may never learn to read or write well and are usually helped by training for occupations or career paths that do not require strong language skills.
Children with dyslexia often need and benefit from psychotherapy because of their struggles with low self-esteem. Many come to feel that they are stupid or less capable than they really are; they are likely to drop out of school if they are not diagnosed and treated early.
The prognosis of dyslexia is difficult to predict because an individual child's outcome depends on a number of factors: the severity of the child's language difficulties; the stage at which the dyslexia is diagnosed; the supportiveness of the child's family; the presence of other health problems; and the quality of supplemental teaching and tutoring that the child receives. Many people with dyslexia, however, do achieve personal and professional success; some go on to complete advanced degrees while others do well in such fields as business and the performing arts.
There is no known way to prevent dyslexia.
Research in dyslexia is focused not only on experimentation with new types of educational techniques but also on research into the genetic factors involved in dyslexia. In addition, ongoing work with such tools as magnetic resonance imaging and positron emission tomography (PET) may yield new insights into the structural differences between the brains of children with dyslexia and the brains of children with normal language skills.
Still another area of research is the relationship between specific languages and children's difficulty in learning to read or speak. Some scientists have suggested, for example, that English-speaking children have a harder time learning to read than Italian-speaking children because English has many more irregular spellings and pronunciations than Italian.
SEE ALSO Developmental disability
WORDS TO KNOW
Decoding: In education, the ability to associate letters of the alphabet with sounds.
Neurologist: A doctor who specializes in diagnosing and treating disorders of the nervous system.
Hultquist, Alan M. What Is Dyslexia?: A Book Explaining Dyslexia for Kids and Adults to Use Together. Philadelphia: Jessica Kingsley Publishers, 2008.
Moats, Louisa Cook, and Karen E. Dakin. Basic Facts about Dyslexia and Other Reading Problems. Baltimore: International Dyslexia Association, 2008.
Moore-Mallinos, Jennifer. It's Called Dyslexia. Hauppauge, NY: Barron's, 2007.
Goodnow, Cecilia. “Author Winkler Turned the Tables on Dyslexia.” Seattle Post-Intelligencer, May 17, 2007. Available online at http://seattlepi.nwsource.com/books/316160_winkler18.html (accessed June 4, 2008).
Schmid, Randolph E. “Study: Dyslexia Differs by Language.” Associated Press, April 8, 2008. Available online at http://www.wtop.com/?nid=106&sid=1382290 (accessed June 4, 2008).
eMedicineHealth. Dyslexia (Learning Disorders: Reading). Available online at http://www.emedicinehealth.com/dyslexia/article_em.htm (updated March 6, 2007; accessed June 4, 2008).
International Dyslexia Association (IDA). Frequently Asked Questions about Dyslexia. Available online at http://www.interdys.org/FAQ.htm (accessed June 4, 2008).
National Institute of Neurological Disorders and Stroke (NINDS). Dyslexia Information Page. Available online at http://www.ninds.nih.gov/disorders/dyslexia/dyslexia.htm (updated December 11, 2007; accessed June 3, 2008).
"Unknown: Dyslexia." UXL Encyclopedia of Diseases and Disorders. . Encyclopedia.com. (November 19, 2018). https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/unknown-dyslexia
"Unknown: Dyslexia." UXL Encyclopedia of Diseases and Disorders. . Retrieved November 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/unknown-dyslexia
Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).
Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.
Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:
Modern Language Association
The Chicago Manual of Style
American Psychological Association
- Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
- In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.