Types of Dyslexia
Updated: Aug 29
Dyslexia affects each person differently. As more and more research is done to identify root causes, symptoms, and effective instructional strategies and programs, researchers have determined multiple types of Dyslexia. In today's post, we'll be discussing three types: Phonological, Surface, and Letter Position (Hanley, 2017).
People with Phonological Dyslexia often have difficulty with phonemic awareness. They have trouble breaking words down into individual sounds. Phonological Dyslexia also affects a person's ability to decode when reading and encode when spelling. They primarily rely on whole word recognition and remembering words by sight.
People with Surface Dyslexia often have poor visual memory, which results in difficulty remembering sight words. It is especially difficult when words don't follow rules and patterns. They have decoding skills, but it is slow and laborious, and they tend to spell words phonetically (sounding them out).
Letter Position Dyslexia
People with Letter Position Dyslexia (LPD) often substitute similarly spelled words. This is because letters "move around" within a word. For example, the words form and from have all 4 of the same letters, but the letters o and r are in different places. Since most words are identifiable regardless of letter position, people with LPD will recognize most words in this way. When it comes to similar-looking words more frequently used in writing, they use this same technique; however, it results in the incorrect reading of the word.
People with LPD also often omit letters appearing more than once in a word. For example, the word drivers has the letter r showing up twice. In this case, a person with LPD may read the word as divers or drives, leaving off one of the letters. Again, this has to do with their ability to recognize most words regardless of letter positioning. The words drivers, divers, and drives all begin and end with the same letters.
Hanley, J.R. (2017). Is there just one dyslexic reader? Evidence for the existence of distinct dyslexic sub-groups. Current Developmental Disorders Report, 4, 101-107. doi: 10.1007/s40474-017-0125-y