Morphological and Semantic Processing in Developmental Dyslexia

Abstract

semantic representations. According to this theoretical approach, dyslexics' impairments in phonological decoding lead to reliance on the lexical route. More recent conceptualizations of dual-route models suggest that the use of morphological information speeds lexical access, with both direct and indirect lexical access via letter co-occurrences, such as complex graphemes and morphemes (e.g., TH, CH and RE, ED, respectively;Grainger & Ziegler, 2011). This provides a theoretical context for the speculation that dyslexics might rely on a lexical route that includes morphemes.Nonetheless, Betjemann and Keenan ( 2008) argued against the notion that semantic processing is a strength in dyslexia, an idea that can be applied equally to morphological processing. The authors explained that dyslexic children rely on semantic cues more than typical readers because they need to compensate for their poor phonological skills when trying to read, rather than because they have particularly strong semantic skills. Like Stanovich's (1980) interactive-compensatory model, Betjemann and Keenan (2008) incorporate the paradoxical hypotheses that dyslexics have impaired morphological and semantic processing, and yet rely greatly on these while reading. Together, these approaches provide theoretical justification for the possibility that dyslexics' established phonological deficits might be associated with relative strengths in morphological and/or semantic processing.

Morphological awareness and reading achievement in university students

“…Outcomes for our second research question were not straightforward to predict. That is, morphological awareness may be an additional and persistent deficit in students with a self-reported history of reading difficulties, as found for younger students with diagnosed disabilities (Deacon et al, 2016) and in some studies of university students with dyslexia. Alternatively, morphological awareness may be a strength for students with a history of reading difficulties as reported in other studies with university students with dyslexia, helping them to read university material.…”

“…It has been shown that morphology has a role in skilled word reading (e.g., Crepaldi, Rastle, Coltheart, & Nickels, 2010;Taft, 1994). Furthermore, both developmental research (Deacon, Tong, & Mimeau, 2016) and theoretical models support the notion that individual differences in morphological processing are related to reading achievement (Scarborough, 2001;Stafura & Perfetti, 2017). Consistent with some research on university students with dyslexia (e.g., Cavalli, Duncan, Elbro, El Ahmadi, & Colé, 2017;Law, Wouters, & Ghesquière, 2015;Martin, Frauenfelder, & Cole, 2014), morphological awareness may also be a strength for students with a selfreported history of reading difficulties, acting as a compensation for core deficits in the word reading of these students.…”

“…There is limited research that simultaneously examines the three reading-related skills included in this study and their relationship to reading comprehension in university students or young adults. Theoretically, morphological awareness is proposed to have a direct influence on reading comprehension (Scarborough, 2001;Stafura & Perfetti, 2017), and this has been found to be the case for elementary and adolescent students (Carlisle, 1995;Deacon et al, 2016;Kirby et al, 2012;Tong, Deacon, Kirby, Cain, & Parrila, 2011). Less is known about the unique contribution of morphological awareness to reading comprehension in university students; however, it has been proposed that over the school years, as words become more structurally complex with increasing text difficulty, the contribution of morphological awareness to reading comprehension should increase (Nagy, 2007).…”

Language and Reading: the Role of Morpheme and Phoneme Awareness

“…In alphabetic orthographies, the involvement of morpheme awareness in developmental dyslexia is still under investigation. Broadly, dyslexics tend to show reading-level appropriate morpheme awareness, an argument against morpheme awareness being a causal factor in dyslexic difficulties [ 65 ••]. Where dyslexics do perform poorly in morphemic tasks, this may simply be due to a lack of phonological transparency in the morphological relationships assessed [ 44 ].…”

Morphological awareness and visual processing of derivational morphology in high-functioning adults with dyslexia: An avenue to compensation?

“…It is theorized that when dealing with novel or less automatized words, dyslexics' phonological impairment limits their reliance on the sublexical route that involves decoding prior to lexical access. Thus, individuals with dyslexia are bound to utilize the lexical route, which in a recent reconceptualization of the dual-route model of reading (Grainger & Ziegler, 2011) has been argued to include not only direct lexical access but also indirect access through the aid of complex graphemes and morphemes (Deacon, Tong, & Mimeau, 2016).…”