Phonological and orthographic spelling in high‐functioning adult dyslexics

Abstract

Despite a history of reading or spelling difficulties, some adults attain age-appropriate spelling skills and succeed at university. We compared the spelling of 29 such high-functioning dyslexics with that of 28 typical students, matched on general spelling ability, and controlling for vocabulary and non-verbal intelligence. Participants wrote derived real and pseudo words, whose spelling relationship to their base forms was categorized as phonologically simple (apt-aptly), orthographically simple (deceit-deceitful), phonologically complex (ash-ashen), or orthographically complex (plenty-plentiful). Dyslexic participants spelled all word and pseudoword categories more poorly than controls. Both groups spelled simple phonological words best. Dyslexics were particularly poor at spelling simple orthographic words, whose letter patterns and rules must likely be memorized. In contrast, dyslexics wrote more plausible spellings of orthographic than phonological pseudowords, but this might be an artefact of their more variable spelling attempts. These results suggest that high-functioning dyslexics make some use of phonological skills to spell familiar words, but they have difficulty in memorizing orthographic patterns, which makes it difficult to spell unfamiliar words consistently in the absence of sufficient phonological cues or orthographic rules.

Orthographic processing efficiency in developmental dyslexia: an investigation of age and treatment factors at the sublexical level

“…For instance, even with practiced words, second-to sixth-grade children with learning disorders were unable to organize and rapidly access previously learned information for spelling (Gerber, 1984). Kemp, Parrilla and Kirby (2008) also find that adults with dyslexia make use of phonological skills to spell familiar words, but that they have "particular difficulty with the simple orthographic words, which required memory for correct letter sequences" (p. 117). Children with binocular instability as well rely more on phonology than visual memory for spelling, indicating that these children have restricted access to orthographic images (Cornelissen, Bradley, Fowler & Stein, 1994).…”

Developmental Dyslexia in Adults: Behavioural Manifestations and Cognitive Correlates

“…Previous studies show that English adults with dyslexia have deficits in phoneme awareness (Lefly & Pennington, 1991) and phonological processing (Gottardo, Siegel, & Stanovich, 1997;Snowling et al, 1997) and that they demonstrate inaccurate and slow word recognition skills (Bruck, 1990), poor nonword reading (Hanley, 1997;Snowling et al, 1997) and poor spelling (Everatt, 1997;Kemp, Parrila, & Kirby, 2009). Previous studies show that English adults with dyslexia have deficits in phoneme awareness (Lefly & Pennington, 1991) and phonological processing (Gottardo, Siegel, & Stanovich, 1997;Snowling et al, 1997) and that they demonstrate inaccurate and slow word recognition skills (Bruck, 1990), poor nonword reading (Hanley, 1997;Snowling et al, 1997) and poor spelling (Everatt, 1997;Kemp, Parrila, & Kirby, 2009).…”

Assessment of lexical and non-lexical spelling in students in Grades 1–7

“…In the English orthography, there are at least five relatively distinct sources of knowledge that contribute to accurate spelling (e.g. Bourassa & Treiman, 2001;Egan & Tainturier, 2011;Joshi, Treiman, Carreker, & Moats, 2008;Kemp, Parrila, & Kirby, 2009;Moats, 2009): (1) knowing how to translate sounds into letters (spelling phonics, or "non-lexical spelling"), (2) orthographic memory (sight word knowledge, or "lexical spelling"), (3) semantic principles, (4) morphology and (5) etymology.…”