Individual differences in underlying cognitive correlates of reading and arithmetic in 5-year olds

Arithmetic and reading constitute two quintessential building blocks of children’s elementary school education. Prior cognitive research has predominantly focused on identifying the cognitive underpinnings of (future) individual differences in arithmetic or reading. This research has revealed distinct domain-specific cognitive correlates for each learning domain separately. Studies from the reading research field, have repeatedly demonstrated that, phonological awareness underlies individual differences in learning to read (i.e., Melby-Lervåg et al., 2012). Interestingly, phonological awareness, considered a reading-specific cognitive correlate, has also been associated to individual differences in arithmetic learning (i.e., Fuchs et al., 2005). Arithmetic and reading are consistently found to be highly correlated (i.e., Simmons & Singleton, 2008) and it has even been suggested that these academic abilities share genetic influences (so-called “generalist genes”) (i.e., Kovas et al., 2007). Additionally, learning difficulties characterized by specific deficits in arithmetic (dyscalculia) or reading (dyslexia) co-occur frequently (e.g., Boets & De Smedt, 2010; Simmons & Singleton, 2008). It is consequently surprising that research on arithmetic and reading has mostly occurred in isolation from each other. Against this background, the present study aims to investigate individual differences in arithmetic and reading simultaneously, in order to reveal underlying cognitive mechanisms that are shared between these learning abilities, rather than focusing on what sets arithmetic and reading development apart. Firstly, this study explored associations between levels of early arithmetic as well as early reading before formal instruction. We further investigated how early arithmetic and early reading levels correlate with cognitive skills known to predict future fluency in arithmetic and/or reading. This allowed us to reveal specific and shared cognitive skills for arithmetic and reading. Participants were 188 children (101 girls, 87 boys) in the last year of Kindergarten in Flanders (M = 5 years, 8 months; SD = 4 months), who had not yet received formal education. Early arithmetic was assessed with concrete materials and with symbols (2 + 3 = ?). Early reading was tested with an active letter knowledge task. The measured cognitive skills were: Symbolic and non-symbolic comparison, numeral recognition and phonological awareness (end-phoneme identification; end-rhyme identification). Regression analyses and Bayesian hypothesis testing revealed strong associations between levels of early arithmetic and early reading, even after controlling for age, sex and intellectual ability. Numeral recognition appeared the most important cognitive correlate of early arithmetic and early reading. Phonological awareness correlated with symbolic arithmetic and early reading, but not with concrete arithmetic. The current findings indicate that especially preschoolers’ ability to identify abstract symbols (i.e., Arabic numerals) represents an important and shared cognitive correlate of learning to calculate, but also to read. It consequently constitutes a risk factor for developing difficulties in arithmetic as well as reading. Screening this shared cognitive correlate might be useful to detect preschoolers at risk for learning difficulties.status: publishe