Vocabulary skills are well developed in university students with dyslexia: Evidence from multiple case studies

Abstract

Most studies in adults with developmental dyslexia have focused on identifying the deficits responsible for their persistent reading difficulties, but little is known on how these readers manage the intensive exposure to written language required to obtain a university degree. The main objective of this study was to identify certain skills, and specifically vocabulary skills, that French university students with dyslexia have developed and that may contribute to their literacy skills. We tested 20 university students with dyslexia and 20 normal readers (matched on chronological age, gender, nonverbal IQ, and level of education) in reading, phonological, vocabulary breadth (number of known words), and vocabulary depth (accuracy and precision) tasks. In comparing vocabulary measures, we used both Rasch model and single case study methodologies. Results on reading and phonological tasks confirmed the persistence of deficits in written word recognition and phonological skills. However, using the Rasch model we found that the two groups performed at the same level in the vocabulary breadth task, whereas dyslexics systematically outperformed their chronological age controls in the vocabulary depth task. These results are supplemented by multiple case studies. The vocabulary skills of French university students with dyslexia are well developed. Possible interpretations of these results are discussed.

Socio-emotional and cognitive resilience in children with reading disabilities

“…Other studies have similarly found that children with RD can rely on morphological structure to decode words faster, despite decoding difficulties [38,39]. Vocabulary skills have also been implicated as a compensatory mechanism for college students with RD [40], and have been shown to mediate between impaired verbal working memory and oral reading fluency in adolescents with RD [41]. More superior verbal reasoning skills in general have been shown to explain higher reading, spelling, morphological, and syntactic skills in students with RD [42].…”

Phonemic—Morphemic dissociation in university students with dyslexia: an index of reading compensation?

“…Secondly, since the semantic knowledge associated with words seems to be preserved both in children (Vellutino et al, 1995) and adults (Cavalli et al, 2016;Elbro et al, 1994) with dyslexia, and since neuroimaging studies show no differences between the spatial distribution of the brain areas involved in semantic processing by dyslexic and skilled readers (Helenius, Salmelin, Service, & Connolly, 1999;Rüsseler, Becker, Johannes, & Münte, 2007), we assume that dyslexics are likely to capitalize on the semantic dimension of morphology to develop morphological knowledge. In accordance with this hypothesis, a recent study conducted in Dutch showed that in the context of a productive dictation task, university students with dyslexia made slightly fewer grammatical errors and proportionally more phonological and orthographic errors than their control peers in spelling words and sentences to dictation.…”

A Review about Functional Illiteracy: Definition, Cognitive, Linguistic, and Numerical Aspects

“…In contrast, dyslexic adults performed well in the semantic fluency task (Hatcher et al, 2002) and vocabulary tasks (e.g., Cavalli et al, 2016) but the success of children were mixed (Joanisse et al, 2000; White et al, 2006; Everatt et al, 2008; Landerl et al, 2009; Varvara et al, 2014). …”