Instinctive and learned math abilities are correlated

When young schoolchildren master the addition tables, the knowledge they obtain relies on symbolic numerical representation. But humans, and even some animals, also have an instinctive nonsymbolic “approximate number system” (ANS) that we use to represent a quantity of items without counting. Justin Halberda of the Johns Hopkins University and colleagues at JHU and the Kennedy Krieger Institute have now established that a person’s ability in applying the instinctive ANS goes hand in hand with learned symbolic numerical ability as measured by standardized exams. In their ANS test, Halberda and colleagues showed 14-year-olds a series of figures such as the one reproduced here. After viewing an image for 0.2 second, each subject attempted to identify which color dot—yellow or blue—was more numerous. To quantify a subject’s ANS acuity, the researchers determined the minimum percent difference that could be reliably discriminated in the number of dots. The ANS ability displayed by...