Dyslexia, or developmental reading

Dyslexia, or developmental reading disorder,[1] is characterized by difficulty with learning to read fluently and with accurate comprehension despite normal or above-average intelligence.[2][3] This includes difficulty with phonological awareness, phonological decoding, processing speed, orthographic coding, auditory short-term memory, language skills/verbal comprehension, and/or rapid naming.[4][5][6]

Dyslexia is the most common learning difficulty[7] and most recognized reading disorder. There are other reading difficulties that are unrelated to dyslexia.

Some see dyslexia as distinct from reading difficulties resulting from other causes, such as a non-neurological deficiency with vision or hearing, or poor or inadequate reading instruction.[8][9] 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 (e.g. an auditory processing disorder, an attention deficit hyperactivity disorder, a visual processing disorder) and co-occurring learning difficulties (e.g. dyscalculia and dysgraphia).[10][11][12][13][14][15] Although it is considered to be a receptive (afferent) language-based learning disability in the research literature, dyslexia also affects one's expressive (efferent) language skills.[16] Researchers at MIT found that people with dyslexia exhibited impaired voice-recognition abilities.[17] A study published online (and in the July issue of the American Journal of Human Genetics), reported a possible genetic origin to the disorder, and other learning disabilities, that could help lead in some cases to earlier diagnoses and more successful interventions.