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DictionarySeelearning disabilityEncyclopediaSeelearningLearning Disorders
Learning Disorders DefinitionLearning disorders are academic difficulties experienced by children and adults of average to above-average intelligence. People with learning disorders have difficulty with reading, writing, mathematics, or a combination of the three. These difficulties significantly interfere with academic achievement or daily living.DescriptionLearning disorders, or disabilities, affect approximately 2 million children between the ages of six and 17 (5% of public school children), although some experts think the figure may be as high as 15%. These children have specific impairments in acquiring, retaining, and processing information. Standardized tests place them well below their IQ range in their area of difficulty. The three main types of learning disorders are reading disorders, mathematics disorders, and disorders of written expression. The male: female ratio for learning disorders is about 5:1.Reading disordersReading disorders are the most common type of learning disorder. Children with reading disorders have difficulty recognizing and interpreting letters and words (dyslexia). They aren't able to recognize and decode the sounds and syllables (phonetic structure) behind written words and language in general. This condition lowers accuracy and comprehension in reading.Mathematics disordersChildren with mathematics disorders (dyscalculia) have problems recognizing and counting numbers correctly. They have difficulty using numbers in everyday settings. Mathematics disorders are typically diagnosed in the first few years of elementary school when formal teaching of numbers and basic math concepts begins. Children with mathematics disorders usually have a co-existing reading disorder, a disorder of written expression, or both.Disorders of written expressionDisorders of written expression typically occur in combination with reading disorders or mathematics disorders or both. The condition is characterized by difficulty with written compositions (dysgraphia). Children with this type of learning disorder have problems with spelling, punctuation, grammar, and organizing their thoughts in writing.Causes and symptomsLearning disorders are thought to be caused by neurological abnormalities that trigger impairments in the regions of the brain that control visual and language processing and attention and planning. These traits may be genetically linked. Children from families with a history of learning disorders are more likely to develop disorders themselves. In 2003 a team of Finnish researchers reported finding a candidate gene for developmental dyslexia on human chromosome 15q21.Learning difficulties may also be caused by such medical conditions as a traumatic brain injury or brain infections such as encephalitis or meningitis.The defining symptom of a learning disorder is academic performance that is markedly below a child's age and grade capabilities and measured IQ. Children with a reading disorder may confuse or transpose words or letters and omit or add syllables to words. The written homework of children with disorders of written expression is filled with grammatical, spelling, punctuation, and organizational errors. The child's handwriting is often extremely poor. Children with mathematical disorders are often unable to count in the correct sequence, to name numbers, and to understand numerical concepts.DiagnosisProblems with vision or hearing, mental disorders (depression, attention-deficit/hyperactivity disorder), mental retardation, cultural and language differences, and inadequate teaching may be mistaken for learning disorders or complicate a diagnosis. A comprehensive medical, psychological, and educational assessment is critical to making a clear and correct diagnosis.A child thought to have a learning disorder should undergo a complete medical examination to rule out an organic cause. If none is found, a psychoeducational assessment should be performed by a psychologist, psychiatrist, neurologist, neuropsychologist, or learning specialist. A complete medical, family, social, and educational history is compiled from existing medical and school records and from interviews with the child and the child's parents and teachers. A series of written and verbal tests are then given to the child to evaluate his or her cognitive and intellectual functioning. Commonly used tests include the Wechsler Intelligence Scale for Children (WISC-III), the Woodcock-Johnson Psychoeducational Battery, the Peabody Individual Achievement Test-Revised (PIAT-R) and the California Verbal Learning Test (CVLT). Federal legislation mandates that this testing is free of charge within the public school system.Key termsDyslexia — An inability to read, write, or spell words in spite of the ability to see and recognize letters. Dyslexia is an autosomal dominant disorder thst occurs more frequently in males.IQ — Intelligence quotient; a measure of intellectual functioning determined by performance on standardized intelligence tests.Phonics — A system to teach reading by teaching the speech sounds associated with single letters, letter combinations, and syllables.TreatmentOnce a learning disorder has been diagnosed, an individual education plan (IEP) is developed for the child in question. IEPs are based on psychoeducational test findings. They provide for annual retesting to measure a child's progress. Learning-disordered students may receive special instruction within a regular general education class or they may be taught in a special education or learning center for a portion of the day.Common strategies for the treatment of reading disorders focus first on improving a child's recognition of the sounds of letters and language through phonics training. Later strategies focus on comprehension, retention, and study skills. Students with disorders of written expression are often encouraged to keep journals and to write with a computer keyboard instead of a pencil. Instruction for students with mathematical disorders emphasizes real-world uses of arithmetic, such as balancing a checkbook or comparing prices.PrognosisResourcesBooksAmerican Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed., revised. Washington, DC: American Psychiatric Association, 2000.Beers, Mark H., MD, and Robert Berkow, MD., editors. "Learning Disorders." In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.PeriodicalsGalaburda, D. M., and B. C. Duchaine. "Developmental Disorders of Vision." Neurologic Clinics 21 (August 2003): 687-707.Gillberg, C., and H. Soderstrom. "Learning Disability." Lancet 362 (September 6, 2003): 811-821.Taipale, M., N. Kaminen, J. Nopola-Hemmi, et al. "A Candidate Gene for Developmental Dyslexia Encodes a Nuclear Tetratricopeptide Repeat Domain Protein Dynamically Regulated in Brain." Proceedings of the National Academy of Sciences in the USA 100 (September 30, 2003): 11553-11558.Taylor, K. E., and J. Walter. "Occupation Choices of Adults With and Without Symptoms of Dyslexia." Dyslexia 9 (August 2003): 177-185.Witt, W. P., A. W. Riley, and M. J. Coiro. "Childhood Functional Status, Family Stressors, and Psychosocial Adjustment Among School-Aged Children with Disabilities in the United States." Archives of Pediatric and Adolescent Medicine 157 (July 2003): 687-695.OrganizationsThe Interactive Guide to Learning Disabilities for Parents, Teachers, and Children. http://www.ldonline.org.Learning Disabilities Association of America. 4156 Library Road, Pittsburg, PA 15234. (412) 341-1515. http://www.ldanatl.org.National Center for Learning Disabilities (NCLD). 381 Park Avenue South, Suite 1401, New York, NY 10016. (410) 296-0232. http://www.ncld.org.OtherLD Online Page. http://www.ldonline.org.learning [lern´ing] (pl. learn·ing) education (def. 2).the acquisition of knowledge.learning disorders a group of disorders characterized by academic functioning that is substantially below the level expected on the basis of the patient's chronological age, measured intelligence, and age-appropriate education.lifelong learning the continuation of the process of education throughout life.LegalSeedisorder |