Innate number sense changes with age

New research shows that our ability to rapidly estimate the number of things in a set (an ability called subitizing) peaks around 30 and declines with age.  Researchers posted an experiment online to measure this “number sense”.

This could have implications for the design of displays that require decision making based on judgements of the number of things.  A simple example might be comparing the star ratings on products when shopping online.

The team found that scores on the test improved gradually throughout the school years, peaking around age 30, then declining. Nonetheless, there were large individual differences in scores among people of the same age. Those differences appeared to be modestly linked to school performance: Those with the best innate number sense reported the highest ability in math in school. A subgroup of nearly 500 subjects were also asked to report their math scores on the SAT. Again, a higher innate numbers sense was associated with higher SAT scores.