A 15-month-old nestled in his mother’s lap points curiously at an object in a book he’s never seen before. “Whisk,” coos his mom, answering her son’s implied query. Reading books together is a cherished bonding ritual that takes place in homes across the nation every day, but what exactly is the boy learning during these exchanges? As any parent will tell you, he will point at this same picture when Mom says “whisk” during future story sessions, but what about a real whisk he later sees at a friend’s house? The question of whether children understand that pictures represent real-life objects is at the heart of a recent study conducted at our research center at Northwestern University.
Our work was inspired in part by a previous study that first showed infants a series of pictures of white whisks and then tested whether the babies would choose a 3-dimensional blue whisk as well as, or over, a picture of a white whisk when asked to identify a whisk. Instead, the researchers found very mixed results: at test time, the younger infants were more likely to choose a picture of a white whisk and the older infants chose the picture about half of the time and a real whisk about half the time, almost never selecting both.
So does this mean that babies who see a picture in a story don’t link it to the real-life object it represents? We think they do, and we decided to test our theory at the Project on Child Development! Our researchers thought that having seen only pictures of white objects labeled as whisks might have thrown the babies off at test time—after all, there are many objects in real life, like lemons or crows, that we associate with just one color. So in our study, we read the infants a book with a series of pictures of two different colors of whisks, purple and orange.
Then we performed a series of tests where we asked them to show or give us a whisk. The results were clear: the babies overwhelmingly extended the word “whisk” to the real, three-dimensional object even though it differed in color from the picture they’d previously heard referred to as a “whisk.”
Our study clearly showed that infants as young as 15 months can map words from two-dimensional pictures onto three-dimensional objects in real life. This means that the mom we mentioned at the beginning of our post isn’t just enjoying an important bonding ritual with her son while teaching him the names of objects in a book—she is also teaching him the broader meaning of a word that will enrich his understanding of the world he is enthusiastically discovering all around him!