Babies Look to Mothers for Cues on How to React to the World

Other experiments also show that one-year-olds have a radically new understanding of people. What happens when you show a baby something new, something a little strange, maybe wonderful, maybe dangerous—say, a walking toy robot? The baby looks over at Mom quizzically and checks her out. What does she think? Is there a reassuring smile or an expression of shocked horror? One-year-olds will modify their own reactions accordingly. If there's a smile, they'll crawl forward to investigate; if there's horror, they'll stop dead in their tracks.

Again we can show this quite systematically. For instance, a grown-up can look into two boxes. She looks into one box with an expression of joy and into the other with an expression of complete disgust. Then she pushes the boxes toward the baby, who has never seen inside the boxes. Nevertheless, the baby figures out something about what is inside just by looking at the experimenter's face: the baby happily reaches into the box that made her happy but won't open the box that disgusted her. The baby doesn't just understand that the other person feels happy or disgusted, but also understands that she feels happy about some things and disgusted about others.

When presented with an unknown, the infant will look to the mother's expression to understand how it should react and if it should engage.