The power of imitation: Already in infancy, imitation promotes a general pro-social orientation toward others

In one study, eighteen-month-old infants were either mimicked or not by an experimenter. Later, when this experimenter or a different adult needed help, infants who had been imitated were more likely to help spontaneously. In a second study, five- to six-year-olds interacted with one experimenter who mimicked their choices and another experimenter who made independent choices. The researchers found that the children were more likely to trust the preferences and factual claims of the experimenter who had mimicked them before. These results demonstrate that already in infancy mimicry promotes a general pro-social orientation toward others and that in young children imitation is a powerful means of social influence in development.

Imitation is not only a means by which we learn from others. As adults, we routinely and automatically copy each other's movements, postures, and facial expressions, and this has a variety of positive social consequences. After being mimicked, we behave more helpfully and generously toward others, from picking up others' dropped belongings to giving more money to charity. Much less is known, however, about the social effects of imitation on infants and young children.

Focusing on the social side of imitation, the researchers tested in a first study whether being mimicked increased pro-social behaviour in infants, as it does in adults. To this end, 48 eighteen-month-old infants were either mimicked or not by an experimenter: In the mimic condition, the experimenter immediately copied everything she saw or heard infants do. For example, if infants pointed at the monitor, walked around the room, vocalized, or scratched their head the experimenter copied this. In the no mimic condition the experimenter never copied infants. Instead, for every infant action, she immediately performed a different one. When, in a second step, that experimenter or a different adult needed help picking up sticks that she had "accidentally" dropped or opening a cupboard, it showed that the infants who had previously been mimicked were much more likely to help both adults than infants who had not been mimicked. "Thus, even in infancy, mimicry has positive social consequences: It promotes a general pro-social orientation toward others," says Malinda Carpenter of the Max Planck Institute for Evolutionary Anthropology.

In a second study, the researchers were interested in how being imitated would affect children's susceptibility to social influence; in particular, whether being imitated would increase or decrease children's trust in others. To this end, 32 five- to six-year-old children first took part in an "imitation phase" in which an assistant showed them and the experimenters some photographs of animals. For half of the children, the assistant placed one photograph between the child and the experimenters and asked the child 'Which animal do you like best? Show me!' Once the child had made his or her choice, the two experimenters chose their favourite animals: While the mimic imitated the child's choice, the non-mimic made an independent choice. For the other half of the children, the assistant asked the child a factual question about the animals depicted, for example, 'Look! One of these three animals has poisonous spines and the other two do not. Which of these animals do you think has poisonous spines? Show me!' Once the child had made his or her choice, the two experimenters took their turns. Once again, the mimic imitated the child's choice while the non-mimic made an independent choice.

The children were then presented with two tests. In a preference test, the experimenters offered conflicting preferences for the contents of two identical boxes; then children were asked to choose a box. In a factual claims test, the experimenters gave conflicting information about which object a novel word referred to, and children were then asked to apply the word to one of the objects. "Children were much more likely to endorse both the preferences and the factual claims of the experimenter who had mimicked them," says Harriet Over of the Max Planck Institute for Evolutionary Anthropology. "These results demonstrate that imitation is a powerful form of social influence in children, as it is in adults, impacting the extent to which children are influenced by the preferences and opinions of those around them." Future research should investigate the boundary conditions of the positive consequences of imitation, and whether imitation ever has negative consequences, say the researchers.