Number sense in kindergarten children: Factor structure and working memory predictors

• The factor structure of number sense and working memory predictors are investigated.
• Number sense factors are symbolic and nonsymbolic number processing.
• Symbolic processing is predicted by central executive and visuospatial sketchpad.
• Nonsymbolic processing is predicted by central executive, but not slave systems.

In the current study, the factor structure of number sense, or the ability to understand, use, and manipulate numbers, was investigated. Previous analyses yielded little consensus concerning number sense factors, other than a distinction between nonsymbolic and symbolic processing. Furthermore, associations between number sense factors and working memory components were investigated to gain insight into working memory involvement in number sense. A total of 441 Dutch kindergartners took part in the study. The factor structure of number sense and associations with working memory were tested using structural equation modelling. Results indicated that there was a distinction between nonsymbolic and symbolic number processing. Nonsymbolic processing was predicted by central executive performance, and symbolic processing was predicted by both central executive and visuospatial sketchpad performance. This implies that symbolic and nonsymbolic processing are distinguishable at this age, and that working memory involvement in symbolic processing is different from that in nonsymbolic processing.