Insight into quantities maxes out in adulthood and may influence math achievement
Even 6-month-old babies can rapidly estimate approximate numbers of items without counting. But surprisingly, an apparently inborn sense for numbers doesn’t top out until around age 30.
Number sense precision gradually declines after that, generally falling to preteen levels by about age 70, say psychologist Justin Halberda of Johns Hopkins University in Baltimore and his colleagues. They report the findings, based on Internet testing of more than 10,000 volunteers ages 11 to 85, online the week of June 25 in the Proceedings of the National Academy of Sciences.
“I expected to see some improvement in number sense into preschool or maybe early elementary school, but not up to age 30,” Halberda says.
Evidence of critical mental abilities peaking after young adulthood is rare but has been reported for face memory (SN: 1/1/11, p. 16).
Participants in the new study completed a g