Research-based Definition of Dyslexia

(Revised January 1, 2003)

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 experience that can impede growth of vocabulary and background knowledge.

International Dyslexia Association’s Definition

Dyslexia is a neurologically-based, often familial, disorder that interferes with the acquisition and processing of language.  Varying in degrees of severity, dyslexia causes difficulty in receptive and expressive language.

Symptoms can include difficulty in phonological processing, reading, writing, spelling, handwriting, and sometimes, in arithmetic.

Dyslexia is not the result of lack of motivation, sensory impairment (such as eyesight or hearing), inadequate instructional or environmental opportunities, or other limiting conditions.  But dyslexia may occur together with those conditions.

Although dyslexia is lifelong, individuals with dyslexia frequently respond successfully to timely and appropriate interventions.

Dyslexia is a language processing disorder that affects about one-fifth of the population!