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Dyslexia

Reading And The Brain, How We Read, Causes Of Dyslexia, Treating DyslexiaFuture developments



Dyslexia is a disorder that falls under the broad category of learning disabilities. It is often described as a neurological syndrome in which otherwise normal people have difficulty reading and writing. Frequently, dyslexia is defined by what it is not—dyslexia is not mental retardation, a psychiatric or emotional disorder, or a vision problem. Dyslexia is not caused by poverty, psychological problems, lack of educational opportunities, or laziness; those who are identified as dyslectic have normal or above-normal intelligence, normal eyesight, and tend to come from average families.



There are dozens of symptoms associated with dyslexia. In reading and writing, those with dyslexia may skip words, reverse the order of letters in a word (for instance, writing or reading "was" for "saw"), or drop some letters from a word (for example, reading "run" instead of "running"). They may concoct strange spellings for common words, have difficulty remembering and following sequences (like reciting the alphabet in order), and have cramped, illegible handwriting. There is often a gap between what the person seems to be capable of doing and performance; it's not unusual for a student with dyslexia to earn straight As in science and fail English.


Researchers are exploring the use of various drugs known to affect chemical activity in the brain. Although fMRI can not yet be used as a diagnostic tool, its use has proven the neurobiologic root to dyslexia and may help in devising methods of treatment.


Resources

Books

Selikowitz, Mark. Dyslexia and Other Learning Difficulties: The Facts. New York: Oxford University Press, 1993.

Ziminsky, Paul C. In a Rising Wind: A Personal Journey Through Dyslexia. Lanham: University Press of America, 1993.

Other

Facts About Dyslexia. National Institutes of Health, National Institutes of Child Health and Human Development. Washington, DC: U.S. Government Printing Office, 1993 (U.S. Government Printing Office NIH Publication 93-0384-P).


A. Mullig

KEY TERMS

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Angular gyrus

—A portion of the brain directly related to reading, located in the left side of the brain.

Frontal lobe

—A portion of the brain that controls planning, problem solving, and writing. Broca's area (the part of the brain that coordinates the movements of muscles used in speech) is located in the frontal lobe.

Occipital lobe

—The portion of the brain that accepts visual signals and combines and interprets them.

Wernicke's area

—The portion of the left side of the brain that stores and retrieves words and word patterns.

Additional topics

Science EncyclopediaScience & Philosophy: Direct Variation to Dysplasia