Many studies tested the association between numerical magnitude processing and mathematics achievement,
but results differ depending on the number format used. For symbolic numbers (digits), data are
consistent and robust across studies and populations: weak performance correlates with low math
achievement and dyscalculia. For non-symbolic formats (dots), many conflicting findings have been reported.
These inconsistencies might be explained by methodological issues. Alternatively, it might be that the
processes measured by non-symbolic tasks are not critical for school-relevant mathematics. A few
neuroimaging studies revealed that brain activation during number comparison correlates with children's
mathematics achievement level, but the consistency of such relationships for symbolic and non-symbolic
processing is unclear. These neurocognitive data provided ground for educational interventions, which seem
to have positive effects on children's numerical development in (a)typical populations.
& 2013 Published by Elsevier GmbH