Although decades of research supports the idea that newborn babies can imitate facial and hand gestures, facial expressions and sounds beginning from their first weeks of life after birth, a new study suggests that very young infants are not capable of imitation after all.

"Numerous studies from the 1980s and 90s indicated no imitation by newborns, while others claimed it was there," said Virginia Slaughter, a researcher from the University of Queensland in Australia and senior author of the study. "We wanted to clear up the confusion because the 'fact' that newborns imitate is widely cited, not just in the fields of psychology, neuroscience, and pediatrics, but also in popular sources for parents."

Slaughter suggests that earlier work that pointed to imitation capabilities in newborn babies presented them with a limited number of gestures that were highly likely to be enacted even in the absence of imitation.

"If infants also increase their tongue protrusions when an adult models a happy face or finger pointing, then it's not a case of imitation, but probably excitement at seeing an adult do something interesting," she said. "We eliminated this problem by assessing infants' responses to a wide range of different models."

The team presented 106 infants with nine social and two non-social models and scored their responses to the behaviors at one, two, six and nine weeks of age. The results revealed that infants did not imitate any of the behaviors that they observed and were just as likely to produce a different gesture than one that matched adult behavior.

The University of Queensland study suggests that imitation isn't an innate behavior that exists even shortly after birth, but a learned one that the babies acquire in the months following birth. Slaughter even suggests that babies might learn the act of imitation by observing other people imitate them.

"Infants aren't born with the ability to copy what other people do, but they acquire that skill during the first months of life," she said. "One possibility is that being imitated plays a role in this acquisition. In another study from our lab, we found that parents imitate their babies once every two minutes on average; this is a powerful means by which infants can learn to link their gestures with those of another person."

The findings were published in the May 5 issue of Current Biology.