dyslexia

Dyslexia is a learning difference characterized by persistent difficulties with accurate and fluent word recognition and spelling, despite normal intelligence and adequate instruction. It is typically linked to deficits in phonological processing, the ability to segment and manipulate sounds in spoken language. Dyslexia is a neurobiological condition with a strong genetic component and varies in severity. It is not the result of vision problems, lack of schooling, or low motivation.

Signs include slow or inaccurate reading, difficulty decoding unfamiliar words, poor spelling, and trouble with phonemic awareness. People may have strengths in reasoning, creativity, or visual-spatial skills. Early indicators can appear in kindergarten or first grade but may not be noticed until later.

Causes and risk factors: genetic influence; brain differences in areas supporting reading and phonological processing; family history; environmental and instructional factors may affect development but do not cause dyslexia by themselves. It is not caused by poverty or poor teaching alone.

Diagnosis and assessment: Official diagnosis typically follows a comprehensive evaluation by specialists in learning disorders, combining tests of reading, listening, writing, language processing, and cognitive abilities. Current practice emphasizes identifying specific cognitive profiles and functional impairments rather than relying on IQ disparities alone.

Management and supports: Evidence-based instruction, especially structured literacy with explicit, systematic instruction in phonics, phonological awareness, decoding, and fluency. Accommodations in school, such as extra time, audio records, and assistive technology. Early identification and consistent instruction improve outcomes; many individuals with dyslexia achieve literacy and academic success with ongoing support.

Prevalence and public health: Affects approximately 5-10% of the population; occurs worldwide across languages, with variation depending on orthography. The condition is chronic but manageable with appropriate education and supports. Research continues into genetic, neural, and instructional factors.