“Dyslexia is a specific learning disability that is neurobiological 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 of Directors, Nov. 12, 2002. Many state education codes, including New Jersey, Ohio and Utah, have adopted this definition. Learn more about how consensus was reached on this definition: Definition Consensus Project.

Dyslexia symptoms can vary from person to person, but common markers include:

• Struggling with phonemic awareness, or the ability to differentiate between and use individual sounds in words

• Slow or distorted phonological processing, or differentiating between various phonemes (or “speech sounds”)

• Reading or writing letters or words out of order; poor spelling

• Reading slowly or with frequent pauses

• Difficulty sounding out unknown words

• Misuse or total disregard of punctuation

• Difficulty mastering correct spelling or age-appropriate vocabulary

• Trouble with handwriting

• Difficulty recalling known words

• Delayed speech development

• Trouble rhyming

• Short attention span

• Difficulty following directions

• Trouble distinguishing letters, numerals or sounds