Dutch dyslexic adolescents: phonological-core variable-orthographic differences

Abstract

The phonological-core variable-orthographic differences (PCVOD) model [van der Leij, & Morfidi (2006). Journal of Learning Disabilities, 39,[74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90] has been proposed as an explanation for the heterogeneity among dyslexic readers in their profiles of reading-related subskills. The predictions of this model were investigated in a sample of 72 Dutch secondary school students (dyslexics and controls). First, the PCVOD assumption was confirmed that phonological processing and orthographic competence are independent contributors to the prediction of reading fluency and spelling. Among the phonological processing tasks, phonological recoding explained substantial unique variance, but not phonemic awareness or rapid serial naming. Next, the dyslexic readers were divided into two subgroups based on high (ORTH + ) and low levels (ORTH -) of orthographic competence. Both subgroups performed below controls on all measures tapping phonological processing, reading and spelling but the ORTH + group performed as well as nondisabled controls on Dutch and English orthographic choice. As predicted by the model, there were no differences between the subgroups on the tasks that depend on phonological processing, with or without reading. There were differences on Dutch word reading fluency and spelling. Furthermore, the ORTH + subgroup outperformed ORTH -on tasks demanding speeded word processing such as 'flashed' presentation. This finding was independent of lexicality (words or pseudowords), language (Dutch or English) or response mode (lexical decision or typing), but restricted to silent reading. This supports the view that the ORTH + subgroup is better at identifying larger orthographic units. There was no indication of differences between the subgroups in reading experience. Our data, therefore, support the PCVOD model.

Dutch children at family risk of dyslexia: precursors, reading development, and parental effects

“…Together with the finding that this group remains to lag behind in pseudoword reading, these results might be taken to suggest that at-risk non-dyslexics need more exposure to letters and words to reach the same level as the controls. As a related possibility, it could be that this group has a larger orthographic competence, the ability to store associations between written and spoken word forms at the word and subword levels (Bekebrede, van der Leij, & Share, 2009), than their at-risk dyslexic peers. At the beginning of learning to read differences between the at-risk dyslexic and non-dyslexic groups are relatively small, as word reading is highly dependent on phonological recoding.…”

Predictive and concurrent relations between literacy skills in Grades 1 and 3: A longitudinal study of Italian children

“…For many transparent orthographies, such as German (Wimmer & Mayringer, 2002), Spanish (Defior, Jimenez Fernandez, & Serrano, 2009), Dutch (Bekebrede, van der Leij, & Share, 2009) and Italian too (Angelelli, Notarnicola, Judica, Zoccolotti, & Luzzatti, 2010), regularity refers more to graphemeephoneme (forward regularity) than to phonemeegrapheme (backward regularity) conversion. In fact these orthographies present a certain degree of ambiguity in the sound-to-print direction as some phonological strings have more than one possible orthographic solution, though only one is correct.…”

Dutch Dyslexia in Adulthood: Core Features and Variety

“…Instead, the data favor an approach to dyslexic heterogeneity characterized by greater heterogeneity in orthographic coding coupled with relative homogeneity as regards phonological deficits as exemplified in the PCVOD model. Bekebrede, van der Leij, and Share (2009) tested the PCVOD model in a study of Dutch adolescents. Supporting the universality of the phonological core hypothesis, all dyslexics performed poorly on phonological coding and phonological recoding (pseudoword reading fluency).…”

“…Other predictions addressed the issue of heterogeneity within the dyslexic group. The foundation assumptions of the PCVOD model were tested using the methodology of DUTCH DYSLEXIA IN ADULTHOOD Bekebrede et al (2009). Given that orthographic coding is considered to be only partly parasitic on phonological skills, orthographic coding was expected to account for significant additional variance in fluency of word reading after phonological coding was partialled out.…”

“…Additional external validity was adduced using a stimulus presentation condition that necessitates the processing of larger orthographic units, namely, brief or "flashed" presentation of words (see, e.g., Bekebrede et al, 2009). Presenting words for 200 msec followed by masking deters the use of an exhaustive grapheme-phoneme decoding strategy, and increases reliance on larger (orthographic) units.…”