Contributions of Phonology and Orthography to Spelling in Children with Dyslexia

Abstract

Learning to spell is dependent on a child’s ability to simultaneously process phonological (i.e., related to sounds) and orthographic (i.e., related to letters) information. The contributions of phonological and orthographic processes in children with dyslexia have been explored more in reading than in spelling. Evidence from reading research indicates that children with dyslexia tend to rely on relatively preserved orthographic knowledge to compensate for their phonological weaknesses. More studies are needed in spelling, as existing evidence is not clear as to whether phonological and orthographic processes make joint or separate contributions. The present study used phonological and orthographic neighbors (i.e., words differing by a single sound or letter) to examine processing abilities in children with dyslexia and children with typical reading skills. A total of 57 children with dyslexia (grade 4), age-matched typically developing children (grade 4), and reading-level-matched typically developing children (grades 1 and 2) were recruited from elementary schools in Kansas. Participants were asked to spell and read nonwords that varied in the number of phonological and orthographic neighbors (i.e., dense/large neighborhoods vs. sparse/small neighborhoods). Our results revealed that nonwords with many phonological neighbors facilitated spelling and reading performances, whereas nonwords with many orthographic neighbors did not. Performances were similar between children with dyslexia and typical readers. Our findings do not support the idea of orthographic compensation in children with dyslexia and instead, they suggest that children rely more on their phonological knowledge than their orthographic knowledge. We discuss how our findings inform theoretical models of spelling and reading, and how methodological characteristics may explain discrepancies between our study and previous studies.