Phonological dyslexia

Phonological dyslexia is a reading disability that is a form of alexia (acquired dyslexia), resulting from brain injury, stroke, or progressive illness and that affects previously acquired reading abilities. The major distinguishing symptom of acquired phonological dyslexia is that a selective impairment of the ability to read pronounceable non-words occurs although the ability to read familiar words is not affected. It has also been found that the ability to read non-words can be improved if the non-words belong to a family of pseudohomophones.

Individuals who suffer from phonological dyslexia have the opposite problem to surface dyslexics. These individuals are able to read using the whole word method. However, they struggle when it comes to sounding words out. Phonological dyslexics are able to read familiar words, but have difficulties when it comes to unfamiliar words or non-words that are pronounceable. Several studies have found that many phonological dyslexics have a good reading ability if the individual has developed a large vocabulary prior to suffering from brain damage. These individuals seem to stop developing their vocabulary post-brain damage, which affects their reading capacity.

Phonological dyslexia is a reading disorder in which the patient has impaired reading of nonwords. The symptoms of phonological dyslexia are very similar to those of deep dyslexia. The major difference between these two dyslexias is that phonological dyslexics do not make semantic errors associated with deep dyslexia. Beauvois and Dérouesné (1979) studied the first case of phonological dyslexia and came up with this term. The problem people with phonological dyslexia have is that they are able to read words using the whole word method; however, they are not able to sound words out. This means that they are able to read familiar words, but have difficulties reading new words.

Initially it was believed that the factor causing phonological dyslexia was lexicality; however, other factors such as imageability and concreteness also play a critical role in reading. A study done by Crisp and Lambon Ralph concluded that imageability has a significant effect on phonological dyslexia. The study found that eleven out of the twelve patients had more accuracy when reading words with high imageability. In that study, the patient who was the exception was the least severely damaged, contributing to a view of phonological dyslexia and deep dyslexia as points on a continuum rather than discrete disorders.

...
Wikipedia