Two pennies can be considered the same – both are pennies, just as two elephants can be considered the same, as both are elephants. Analogical ability – the ability to see common relations between objects, events or ideas – is a key skill that underlies human intelligence and differentiates humans from other apes. While there is considerable evidence that preschoolers can learn abstract relations, it remains an open question whether infants can as well.
To trace the origins of relational thinking in infants, the researchers tested whether 7-month-old infants could understand the simplest and most basic abstract relation — that of sameness and difference between two things. Infants were shown pairs of items that were either the same — two Elmo dolls — or different — an Elmo doll and a toy camel — until their looking time declined.
In the test phase, the infants looked longer at pairs showing the novel relation, even when the test pairs were composed of new objects. That is, infants who had learned the same relation looked longer at test pairs showing the different relation during test, and vice versa. This suggests that the infants had encoded the abstract relation and detected when the relation changed.
“We found that infants are capable of learning these relations,” said Ferry, now doing post-doctoral research at the International School for Advanced Studies in Italy. “Additionally, infants exhibit the same patterns of learning as older children and adults — relational learning benefits from seeing multiple examples of the relation and is impeded when attention is drawn to the individual objects composing the relation.”
Susan Hespos, a co-author of the study, and associate professor of psychology at Northwestern’s Weinberg College of Arts and Sciences said, “We show that infants can form abstract relations before they learn the words that describe relations, meaning that relational learning in humans does not require language and is a fundamental human skill of its own.”