Contrary to popular belief, babies under a few months don't grin at you because they're copying your own smile, according to new research.
Many studies have indicated that from birth, infants imitate the behaviours and facial expressions of the adults around them. However, a team of Australian, South African and British researchers have released a study this week that refutes this widespread belief.
"Numerous studies from the 1980s and 90s indicated no imitation by newborns, while others claimed it was there," says Virginia Slaughter, a biologist at the University of Queensland and co-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 paediatrics, but also in popular sources for parents."
The international research team, led by Janine Oostenbroek, a psychologist at the University of York in the UK, exposed more than 100 infants to a broad range of gestures and recorded their responses at one, two, six and nine weeks of age.
The gestures included social cues like adults poking their tongues out, frowning or grinning, as well as non-social cues such as pointing or opening a box.
The findings showed no link between behaviours exhibited by babies in their first few months and the gestures they were exposed to. The babies were just as likely to exhibit gestures they had never seen before as repeat ones they had.
For instance, babies stuck their tongues out just as frequently if they were being exposed to pointing or opening a box, rather than anything to do with mouths or tongues.
The researchers suspect that babies are taught to copy others by adults themselves.
"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," Slaughter says.
The paper cites ‘tongue protrusion’ as the most commonly cited behaviour in studies of infant ‘imitation’, so the researchers gave this action a more detailed analysis.
So, where and when do babies learn to imitate? The researchers suspect that babies are taught to copy others by adults themselves – we teach them to imitate because we spend so much time imitating 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," Slaughter says. "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."
Interestingly, the research team had not set out to disprove the imitation theory. In fact, they were looking to study whether imitation levels in infancy had any impact on social development later in the child’s life.
The team is keen to extend their study into infants past one year of age to find out more about how imitation develops.
The research was published this week in Current Biology.
Amy Middleton is a Melbourne-based journalist.
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