This revision: 23rd July 2013 .
Read Full Article at Wikipedia
Dyslexia is a learning disability that impairs a person's fluency or comprehension accuracy in being able to read, and which can manifest itself as a difficulty with phonological awareness, phonological decoding, processing speed, orthographic coding, auditory short-term memory, language skills/verbal comprehension, and/or rapid naming.
Dyslexia is distinct from reading difficulties resulting from other causes, such as a non-neurological deficiency with vision or hearing, or from poor or inadequate reading instruction. It is believed that dyslexia can affect between 5 and 10 percent of a given population although there have been no studies to indicate an accurate percentage.
There are three proposed cognitive subtypes of dyslexia (auditory, visual and attentional), although individual cases of dyslexia are better explained by specific underlying neuropsychological deficits and co-occurring learning disabilities (e.g. attention-deficit/hyperactivity disorder, math disability, etc.).
Reading disability, or dyslexia, is the most common learning disability. Although it is considered to be a receptive language-based learning disability in the research literature, dyslexia also affects one's expressive language skills. Researchers at MIT found that people with dyslexia exhibited impaired voice-recognition abilities.
Adult dyslexics can read with good comprehension, but they tend to read more slowly than non-dyslexics and perform more poorly at spelling and nonsense word reading, a measure of phonological awareness.
There is no cure for dyslexia, but dyslexic individuals can learn to read and write with educational support. There are techniques and technical aids that can manage or even conceal symptoms of the disorder. Removing stress and anxiety alone can improve written comprehension.
For dyslexia intervention with alphabet writing systems the fundamental aim is to increase a child's awareness of correspondences between graphemes and phonemes, and to relate these to reading and spelling. It has been found that training focused towards visual language and orthographic issues yields longer-lasting gains than mere oral phonological training.
Intervention early on while language areas in the brain are still developing is most successful in reducing long-term impacts of dyslexia.