$Unique_ID{BRK03681} $Pretitle{} $Title{Dyslexia} $Subject{Dyslexia Congenital Word Blindness Primary Reading Disability Specific Reading Disability Developmental Reading Disorder} $Volume{} $Log{} Copyright (C) 1986 National Organization for Rare Disorders, Inc. 207: Dyslexia ** IMPORTANT ** It is possible the main title of the article (Dyslexia) is not the name you expected. Please check the SYNONYMS listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Congenital Word Blindness Primary Reading Disability Specific Reading Disability Developmental Reading Disorder General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Dyslexia is a condition in which an individual with normal vision is unable to interpret written language, and therefore is unable to read. Onset is during childhood, and males are affected most often. Symptoms The primary characteristic of Dyslexia is confusion in the orientation of letters. This is manifested by reading from right to left, failure to see (and sometimes to hear) similarities or differences in letters or words, or inability to work out the pronunciation of unfamiliar words. Attempts to read or write are often characterized by letter and word reversal (e.g., "p" for "g", "saw" for "was"). This condition is typical of normal first- and second-graders, but it persists in the dyslexic child or adult. Educationally, the term Dyslexia is usually applied when a child, usually of average or above average intelligence, is two or more years behind his expected grade level in reading. However, underachievers who are less than two years behind reading level may also be affected. The inability to read is inconsistent with achievement in other school subjects such as arithmetic. Spelling ability may or may not be impaired. The child may not be able to determine left from right. Abnormalities of the senses and obvious neurological impairments are usually absent. The child may be left-handed, right-handed, or able to use both hands with equal skill (ambidextrous). A better than normal facility at mirror-reading or writing is common. In some dyslexic children, images seem to blur at a relatively low speed. In attempting to satisfy demands that he read, a dyslexic child may make up a story if the text contains a picture or may substitute words for those he cannot read. He may not be able to vocalize words, i.e., to read aloud. Symptoms of frustration are inevitable. The reading disability and its effects on learning and school performance may lead to behavior problems, delinquency, aggression, withdrawal, or alienation from other children, parents, and teachers. Early diagnosis from ophthalmic, auditory, psychological, and neurological examinations is important so the defect can be treated before a pattern of frustration and failure is established. Causes The cause of Dyslexia is unknown, but a central nervous system defect in the ability to organize graphic symbols has been suggested. One type of Dyslexia may be caused by a defect in the dorsal part of the brain (cerebellum). Dyslexia is often inherited, so other family members also may be affected. Dyslexia can also result from injury to the language centers in the grey surface of the brain (cerebral cortex), (e.g., head injury). Affected Population Onset of Dyslexia occurs during childhood, and lasts throughout life. However, compensatory strategies can often decrease the impact of this disorder in adulthood. Dyslexia affects males more frequently than females. While a family history of language disorders is common, Dyslexia can sometimes occur during adulthood as a result of injury to the language centers in the cerebral cortex. Related Disorders Alexia is a similar defect in the ability to interpret written language, and the subsequent inability to read. This disorder develops later in life as the result of a neurological lesion. Therapies: Standard Treatment of Dyslexia is by remedial education since there is no medical way to correct perceptual deficits at the present time. Psychological test results help to identify the child's areas of strengths and weaknesses so that a suitable teaching program can be designed. Remedial steps are aimed at using the child's abilities and unimpaired capabilities to compensate for visual symbol deficits. Special education services at school are often necessary to assure that the child can reach his/her potential. Therapies: Investigational This disease entry is based upon medical information available through April 1989. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Dyslexia, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 Orton Dyslexia Society 724 York Road Baltimore, MD 21204 (301) 296-0232 NIH/National Institute of Neurological Disorders & Stroke (NINDS) 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5751 (800) 352-9424 NIH/National Institute of Neurological Disorders & Stroke (NINDS) 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5751 Association for Children and Adults with Learning Disabilities 4156 Library Road Pittsburgh, PA 15234 (412) 341-1515 National Network of Learning Disabled Adults, Inc. P.O. Box Z, E.T. Station Commerce, TX 75428 (214) 886-5937 HEATH Resource Center (Higher Education and the Handicapped) One Dupont Circle, NW Washington, DC 20036 (800) 544-3284 For information on genetics and genetic counseling referrals, please contact: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 8th ed.: Victor A. McKusick; Johns Hopkins University Press, 1986. P. 211. THE MERCK MANUAL 15th ed: R. Berkow, et al: eds; Merck, Sharp & Dohme Research Laboratories, 1987. Pp. 1975, 1980.