Dyslexia is a specific learning disability that is neurological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge. (Adopted by the IDA Board, November 2002. This definition is also used by the National Institutes of Child Health and Human Development (NICHD), 2002.)
Dyslexic individuals have average to above average cognitive abilities; however, they unexpectedly struggle with reading, writing, and spelling. Many dyslexics are quite verbal and perform orally well in school, but their written work is slow and often appears like the work of a younger child. The dyslexic student processes written symbols more slowly than a normal reader and is often slow in completing work. The dyslexic may read a word several times correctly, and then reverse or jumble the letters in the word or omit the word altogether. Reading comprehension is compromised by poor oral fluency and laborious decoding. Listening comprehension of stories is generally average or above average. Achievement in math may not be affected for some dyslexics, although immediate recall of number facts or spatial errors in computing math problems may be problematic.
