Does surface dyslexia/dysgraphia relate to semantic deficits in the semantic variant of primary progressive aphasia?

Publication date: Available online 1 November 2019Source: NeuropsychologiaAuthor(s): Marc Teichmann, Clara Sanches, Julia Moreau, Sophie Ferrieux, Marie Nogues, Bruno Dubois, Meggane Cacouault, Saghie SharifzadehAbstractThe semantic variant of primary progressive aphasia (sv-PPA) is a degenerative condition which causes surface dyslexia/dysgraphia, resulting in reading/writing errors of irregular words with non-transparent grapheme-to-phoneme correspondences (e.g., ‘plaid’) as opposed to regular words (e.g., ‘cat’). According to connectionist models, most authors have attributed this deficit to semantic impairments, but this assumption is at odds with symbolic models, such as the DRC account, stating that the reading/writing of irregulars relies on the mental lexicon. Our study investigated whether sv-PPA affects the lexicon in addition to the semantic system, and whether semantic or lexical deficits cause surface dyslexia/dysgraphia, while challenging the two major models of written language.We explored a cohort of 12 sv-PPA patients and 25 matched healthy controls using a reading and writing task, a semantic task (category decision: living vs. non-living), and a lexical task (lexical decision: word vs. no-neighbor non-word). Correlation analyses were conducted to assess the relationship between reading/writing scores of irregulars and semantic vs. lexical performance. Furthermore, item-by-item analyses explored the consistency of reading/writing errors with item-spe...

Source: Neuropsychologia - November 2, 2019 Category: Neurology Source Type: research