Cross-domain associations of key cognitive correlates of early reading and early arithmetic in 5-year-olds

Disabilities in reading and arithmetic often co-occur, but (dis)abilities in reading and arithmetic have mostly been studied in isolation from each other. This study explicitly focused on the co-development of early reading and early arithmetic before primary education. The Multiple Deficit Model was used as theoretical framework (Pennington, 2006). According to this model, the overlap between early reading and early arithmetic is due to a constellation of shared and unique cognitive correlates. Therefore, we investigated whether key cognitive correlates of one academic ability also correlate with the other. Participants were 188 five-year-old kindergartners who had not yet been formally instructed in reading and arithmetic. Phonological awareness was selected as reading-specific cognitive correlate and (non)symbolic numerical magnitude processing and numeral recognition were considered as arithmetic-specific cognitive correlates. We administered a productive letter knowledge task as a proxy of early reading. Early arithmetic was assessed with simple problems such as 2 + 3 =? . Regression analyses and Bayesian hypothesis testing revealed significant correlations between early reading and early arithmetic before children start primary education. Phonological awareness predicted not only early reading but also, early arithmetic, even when controlling for early reading and arithmetic-specific cognitive correlates. Likewise, numeral recognition predicted not only early arithmetic, but also early reading, even when controlling for early arithmetic and phonological awareness. Phonological awareness and numeral recognition can be considered shared cognitive correlates of both academic domains. In contrast, non-symbolic and symbolic numerical magnitude processing skills were specifically correlated to early arithmetic, and not to early reading, indicating that they are unique to only one academic domain. In line with the Multiple Deficit Model, our data suggest that early reading and early arithmetic have a shared as well as unique underlying cognitive basis. Further unravelling what these academic abilities have in common can be of high value for detecting children at risk already before their transition to formal primary education.