Now listen to part of a lecture in a psychology class. The professor is discussing the mathematical capabilities of babies.
(female professor)Scientists have learned some interesting things about the intellectual abilities of babies. They say there's evidence that babies as young as five months old can do basic arithmetic, that they can add. Scientists think babies know one plus one equals two and not one. The evidence is indirect because obviously you can't ask a five-month old baby to add up some numbers for you.So they devised an experiment where, um, in this experiment a baby is shown a doll on a table. Ok, so the baby looks at the doll. Then the researcher lowers a screen in front of the doll, so now the doll is hidden behind the screen. But the baby has already seen the doll and, so, knows it's there.Well, then the researcher takes a second doll and very obviously places it behind the screen with the first one. Ok, so now you have two dolls behind the scree , right? Well, no, cause what the researcher did was they secretly took away one of the dolls. And then when they raised the screen back up, the baby, well, it expects to see two dolls, right? But there’s only one there! And guess what? The baby surprised! It expects two but it only sees one. How could the researchers tell that the baby surprised? Well, they recorded the baby’s eye movement on camera. And we know that when a baby is surprised by something, a loud noise or an unexpected flash of light maybe, it stares at where the noise or light is coming from. And that’s what the babies in the experiment did. They stared, cause the babies know if you add one doll and one doll, you should have two dolls. So when it sees one doll, then it stares because it’s surprised.
Using the research described by the professor, explain what scientists have learned about the mathematical abilities of babies.
Scientists have learned that 5 month-old babies can add. Since the evidence is indirect, they devise an experiment to prove this. In the experiment, the researchers first show the baby a doll on the table, and lower a screen to hide the doll, but the baby still knows it is there. Then, they obviously add another doll behind the screen. However, after that they secretly take away one of the dolls. So when they raise the screen back up, there is only one doll there. When the researchers observed the baby's eye movement that they had recorded during the experiment, they found that the baby stared when it saw only one doll, since babies usually stare at what surprises them. We can conclude the baby is surprised because the baby knew that one plus one equals two, and had expected two dolls when it saw only one. (143 words)
