The impact of phonological processing on number transcoding

Number transcoding describes the ability to make conversions between verbal and digital-Arabic numerical notations and was found to be a significant predictor of later math achievement. Therefore, it is important to better understand predictors of number transcoding performance. In this context, the present study focused on further investigating the predictive power of three phonological processing abilities (i.e., phonological working memory, phonemic awareness, and lexical access) for children's number transcoding performance. In particular, we were interested in potentially selective associations of phonological processing abilities with specific number transcoding error types (i.e., lexical and syntactic errors). In total, 386 3rd and 4th graders aged 7–11 years were assessed. Results demonstrated that above and beyond age, sex, non-verbal reasoning, and visual-spatial working memory overall number transcoding performance were predicted by phonemic awareness and lexical access. Furthermore, selective associations were observed in that lexical errors were predicted by phonemic awareness and lexical access, whereas syntactic errors were predicted by visual-spatial working memory specifically. Taken together, these results corroborate and further specify the contribution of phonological processing abilities for number transcoding by providing evidence for shared cognitive mechanisms for the acquisition of mathematical and language skills.