Cognitive deficits in Spanish-speaking Mexican children with developmental dyslexia.

Developmental dyslexia (DD) has been related to deficits in multiple cognitive skills. Phonological processing deficits are the most frequently reported in opaque orthographies, but there are few studies of transparent orthographies, such as Spanish. The aim of this study was to comprehensively explore possible deficiencies in cognitive functions in Spanish-speaking Mexican children with DD, to determine whether these deficits can explain problems with decoding fluency and accuracy, and analyze whether they provide support for some of the explanatory hypotheses of DD. An extensive cognitive assessment was performed with Spanish-speaking readers: 40 children (20 girls) with DD (mean age 9.02 years, SD = 1.49) and 40 children (20 girls) who were typical readers (mean age 9.22 years, SD = 1.45). Our results showed that most of the children with DD presented deficits in multiple cognitive skills, although not all of these skills contributed to reading performance. These cognitive deficits were not equally distributed among all children and there was no cognitive skill in which all participants with DD showed poor performance. Our results demonstrated that recognition of letter orientation, phonological awareness, and rapid automatized naming were significant predictors of reading ability. These findings support the idea that reading is a multifactorial process involving many cognitive skills, and its disruption could arise from different causes. The main findings are discussed in relation to the major explanatory hypotheses of DD. (PsycInfo Database Record (c) 2025 APA, all rights reserved).