Put most simply, people with dyslexia have difficulty with the written—and sometimes the spoken—word. A language-based learning disorder, people with dyslexia process and interpret information differently than others. Dyslexia is shown to have neurobiological and genetic causes, and therefore often runs in families. It can often be a lifelong challenge, as it impacts reading, writing, spelling, and sometimes speech.
In the past, dyslexia was mistakenly thought to be a sign of low intelligence, laziness, or the result of vision impairment. On the contrary, most individuals with dyslexia have average to gifted intellect and tend to work very hard academically (and otherwise!) in order to compensate for the challenges dyslexia causes. While vision problems can interfere with the process of reading, scientific studies show that vision problems are not a cause of dyslexia.
Sally Shaywitz, M.D., a leading expert on dyslexia, wrote an article that appeared in Scientific American in 1996. Although the article itself was remarkable, the response to it was even moreso. According to Dr. Shaywitz: “From all parts of the globe came stories of children and adults who were experiencing problems exactly like those described in the article. Diplomats, scientists, and CEOs have all told me about their difficulties with reading. Clearly, dyslexia knows no boundaries, neither geographic nor ethnic nor intellectual.” Full Article Here.
Types of dyslexia
Dyslexia can manifest itself in different ways, with different people exhibiting different signs. It can be developmental, meaning that it develops in childhood (most kids with dyslexia fall into this category); or acquired, resulting from a brain injury (such as a stroke, accident, or other trauma).
Scientific researchers have proposed several other ways of categorizing the various types of dyslexia. Generally, experts recognize the following dyslexia subtypes:
People with phonological dyslexia (also called dysphonetic or auditory dyslexia) have difficulty with phonological awareness and phonics rules. It can be identified by poor “nonword” reading skills; for example, a child may be unable to decipher meaningless, invented words that are used to test phonetic skills (such as “framble” or “zarp”) .
Surface dyslexia (also called dyseidetic or visual dyslexia) is characterized by diffculty with syntax (applying the “rules” of language) and laborious reading, despite the ability to sound out words. Learning to recognize whole words visually is difficult (if not impossible), and deciphering words that don’t follow regular phonetic rules is a challenge. Children with surface dyslexia tend to spell phonetically (for example, “school” might be spelled “skul”).
Semantic dyslexia (also known as dysnomia, anomia or naming-speed deficits) is primarily diagnosed by poor rapid automatic naming (how quickly objects, colors, letters/numbers or other symbols can be properly named aloud). Difficulty with word retrieval and hesitatation in speech is prevalent. Instead of specific nouns, generic words (“thing,” or “place”) or descriptive phrases (“the eating thing” rather than “spoon”) may routinely be used. Substituting a different word for what is actually meant is also common (saying “tornado” when meaning “volcano,” for example).
What is specifically referred to as deep dyslexia (or alexia) is an acquired rather than developmental dyslexia, also characterized primarily by semantic errors.