Orthographic learning in developmental surface and phonological dyslexia

Abstract

Phonological decoding skill has been proposed to be key to successful sight word learning (orthographic learning). However, little is known about how children with phonological dyslexia, who have impaired phonological decoding, acquire sight words, or why children with surface dyslexia can have normal phonological decoding skill yet impaired sight word acquisition. This study addressed this issue by investigating orthographic learning in two 10-year-old children: S.D., with a reading profile of surface dyslexia, and P.D., with a reading profile of phonological dyslexia. They participated in two experiments exploring the role of phonological decoding and paired-associate learning in orthographic learning. The results showed that, first, P.D.'s orthographic learning ability was better than S.D.'s, despite her phonological decoding skills being poorer. Second, S.D. showed impaired paired-associate learning abilities while P.D. did not. Overall, the results indicate that phonological decoding ability does not translate directly to orthographic learning ability, and that paired-associate learning ability may also be associated with success in orthographic learning.

Studies on spelling in the context of dyslexia: a literature review

“…Researchers have highlighted that, beyond phonological decoding difficulties, learning to read new words is a challenge to dyslexic children, especially sight words, which are common words in English language that children deal with in written materials throughout their whole schooling process 22 .…”

“…Research about learning disorder, in special dyslexia, have focused on the difficulties in acquisition of the correspondence between phonemegrapheme 12,18,22,[28][29][30] . The phonic intervention is a way to stimulate phonological skills in advance in dyslexic children 29 and on children that present early learning profile with dyslexic characteristics or other learning disabilities 4 .…”

“…Spelling difficulties have been frequently observed in dyslexic children 1,2,[7][8][9]20,22 and persist until adulthood 14,[23][24][25][26][27] .…”

Specific learning disability

“…Reading disability appears to arise from a broad set of possible neuropsychological processes, in addition to phonological processing problems. These include auditory working memory and a complex set of processes necessary to visually recognise letters and automate sight words …”

“…These include auditory working memory 34 and a complex set of processes necessary to visually recognise letters and automate sight words. 35 Each child may struggle with reading for individually different reasons. This biological and neurophysiological heterogeneity has important implications for selecting interventions intended to remediate weaknesses through repetition-based (neuroplastic) training.…”