Humans are born with an innate number sense or approximate number system:
A few years ago, researchers played newborn infants — as young as seven hours! — recordings of spoken syllables repeated a fixed number of times. In one trial, babies would hear “tuuuuu” four times, for example, whereas in another they’d hear “tu” twelve times. At the same time, the babies were shown pictures of geometric shapes, such as four squares or twelve circles. Somewhat amazingly (at this age, after all, they’re basically blind, sucking potato sacks), the babies matched the number of sounds they heard with the number of shapes they saw. On the trials where they had heard four syllables, they would look longer at pictures of four shapes, and on those with 12 syllables, they’d look longer at pictures of 12 shapes.
The better a baby’s number sense at six months old, the stronger the child’s mathematical abilities three years later, a new PNAS study finds:
The study hinges on a method in which researchers track babies’ eye movements as they watch two video screens at the same time. One screen always shows the same number of dots, but the dots change in size and location. The other screen shows the same thing, except that the number of dots changes as well.
Babies like novelty. In an earlier study using this method, the researchers showed that 6-month-old babies tend to look longer at the screen in which the number of dots changes (the left side of the video above) than the other screen, presumably because they notice the difference in the number of dots and like watching it change.