Babies do not just copy adults, study concludes

Children as young as 14 months make decisions of their own about the best way to do things and do not simply copy adults, a new study has found.

The discovery confirms that humans are even more unlike our closest relatives, chimpanzees and other apes, which simply use the movements they already have or copy those they see without ever trying to find more efficient ones.

For years scientists accepted that infants learnt by emulating their parents, as shown in a seminal study in 1988. That ran a simple experiment in which a group of babies watched while a demonstrator turned on a table-mounted pressure-sensitive light using her forehead, while her hands were on the table beside her. A week later, two-thirds of the babies did the same.

Gyorgy Gergely, who led the new research, said such "emulation" was peculiar to humans. Psychologists believe that the babies copied the demonstrator because, although they could see that they were able to use their hands, they thought that using the head "must offer some advantage".

Dr Gergely and his team of researchers in Hungary repeated the experiment – with one important difference. This time, they also ran another experiment in which the demonstrator had her hands under the table, wrapped in a blanket.

In the first group, who had seen the demonstrator with her hands free, 69 per cent of the babies copied her, using their head to turn on the light.

But in the other group, only 21 per cent did. "It must have seemed sensible to the infants that the demonstrator should use the head action when her hands were occupied. Nevertheless, 79 per cent chose not to imitate her because their own hands were free, presumably concluding that the head action was not the most rational," the researchers, based at the Institute for Psychology and the Hungarian Academy of Sciences, note in the science journal Nature.

More significantly, the babies who watched both demonstrations always used their hands. That suggests that they linked the sensation of touching something to activate it with the response most commonly used to establish contact – their hands.