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What is Dyslexia Really?

Dyslexia is a fundamental deficit in the ability to read efficiently. I cannot emphasize the word efficiently enough, because some people think that dyslexia means a student basically cannot read. I have evaluated over 500 people with dyslexia and of those only one was essentially not able to read (even though he had a very high IQ). First, let’s clarify our terms: dyslexia is the term used in the educational therapy domain to signify a reading deficit. Concurrently, psychologists use the term Reading Disorder to denote dyslexia; these two conditions are usually synonymous, but not always.

Myth: Dyslexia is best detected by noticing students who persistently reverse or switch letters. In fact, only 15% of students who have dyslexia have the propensity to switch letters when writing or reading. Most commonly the letters which baffle students are those that look most alike –eg., p and q, and b and d. If a young student does make these reversals for a prolonged period, this is a strong indicator that he/she probably does have dyslexia.

Fact: Dyslexia is best detected by observing:

  • Weak fluency when reading
  • Awkwardness and embarrassment when reading out loud
  • An inability to sound out new words
  • Difficulty consistently reading known sight words
  • Poor spelling
  • Measured slow word naming speed

This pattern of weaknesses continues into adulthood with spelling skills improving but the lack of reading efficiency persisting. The adult with dyslexia reports poor reading comprehension efficiency.

Dyslexia is a clearly defined condition that can be identified in fMRI scans. The neural circuitry of a person with dyslexia is fundamentally different and less efficient. Brain scans reveal that a person with dyslexia takes 10 times longer to recognize words and the meaning of those words -10 times!!! Imagine that slowness compounded over the course of reading a chapter.

What can be done?

Changing the neural circuitry of the brain to improve this deficit is very difficult and must be done before age 9. By the time most students are identified with the condition, this neural window has closed and working with the symptoms is the best/only method. For adults and teens, reading comprehension, retention, and efficiency can improve by listening to text, rather than reading text. Thus, converting text to speech is very helpful. The core hard-wired deficit in the pace of reading is the reason why additional time is the essential accommodation for students with dyslexia. If poor spelling remains highly problematic, then use of a Word Processor with Spell check is necessary.