Developmental dyscalculia (DD) is a specific learning disability in mathematics that affects around 6% of the population. Currently, the core deficit of DD remains unknown. While the number sense deficit hypothesis suggests that the core deficit of DD lies in the inability to represent nonsymbolic numerosity, the access deficit hypothesis suggests…

Altogether 1,285 Finnish children were followed up from the end of kindergarten through Grade 1. All were nonreaders at school entrance. The aim was to delineate predictors of resistance to treatment that are evidenced as little or no reading progress during Grade 1. On the basis of reading achievement in Grade 1 spring, four subgroups were…