What Is Dyslexia?
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.
-IDA Board of Directors, Nov. 12, 2002
According to the National Center for Improving Literacy, dyslexia affects about one in every five individuals, making it the most commonly diagnosed learning disability. The National Institutes of Health (NIH) describes dyslexia as a brain-based learning disability that specifically impairs a person’s ability to read. The reading impairments associated with dyslexia are also unexpected in that individuals with dyslexia typically demonstrate otherwise typical intellectual functioning and developmental growth. To better understand dyslexia let’s look at what it is and is not.
Dyslexia is Brain-Based
Individuals with dyslexia have fundamental differences in brain regions linked with reading and language which are primarily located in the left hemisphere. Dyslexia affects areas associated with detection and processing of sounds and their corresponding letters. These letter-sound linkages are fundamental to reading. Dyslexia tends to be inherited. A student that has a dyslexic parent or sibling is at a 50% greater risk of having dyslexia.
Dyslexia Impairs the Ability to Read and Spell
Individuals with dyslexia often have difficulty with phonological processing which inhibits the ability to effectively decode blended sounds to form words. They also have difficulty efficiently writing the letters comprising words from memory required for efficient spelling.
What Dyslexia Is Not
Dyslexia is not a result of low intellectual functioning. Having dyslexia does not imply that an individual cannot read. With the appropriate intervention, people with dyslexia can learn to read but may still need to put forth more effort. Individuals with dyslexia do not “see letters of words backwards.” Dyslexia is associated with brain-based phonological impairments, not visual problems.
Helping Students With Dyslexia Succeed
Providing students with dyslexia with evidence-based reading instruction and the necessary supports to succeed involves may individuals within a school system. Schools should:
Screen all students for dyslexia risk
Intensify supports for students who need them to succeed and individualize intervention for students with dyslexia
Provide high-quality, evidence-based reading instruction to all students with or at risk for dyslexia
Continue to nurture students’ interests and strengths to help them become successful learners.