Babies can identify socially dominant people: Study

Washington: Toddlers as young as 17 months can perceive who is dominant and are aware that such people receive more rewards, say scientists who found that social hierarchy is naturally ingrained in infants.

"This tells us that babies are sorting through things at a higher level than we thought," said Jessica Sommerville, professor at University of Washington (UW) in the US.

"They're attending to and taking into consideration fairly sophisticated concepts," Sommerville said.

"If, early on, you see that someone who is more dominant gets more stuff, and as adults, we see that and say that's how the world is, it might be because these links are present early in development," she said.

The study evaluated reactions of 80 toddlers who watched three short videos of puppets in simple social situations.

Researchers measured the length of time children focused on the outcome of each video in an effort to determine what they noticed.

Measuring a baby's "looking time" is a common metric used in studies of cognition and comprehension in infants, researchers said.

"Really young babies can't talk to us, so we have to use other measures such as how long they attend to events, to gauge their understanding of these events," said Elizabeth Enright, a graduate student at UW.

"Babies will look longer at things they find unexpected," said Enright.

For the study, each toddler watched an introductory video at least six times. This brief clip aimed to establish the "dominant" puppet in the scene - the one who appeared to win a minor competition with a second puppet over a special chair.

Then each child watched a second set of videos so that researchers could compare how the toddler reacted to various outcomes.

The researchers employed puppets, rather than people, for the videos because the puppets look essentially the same, offer no facial or other emotional reaction, and don't draw an infant's attention the way that differences among humans might, said Sommerville.

The researchers set up three narrative scenarios using the puppets. In one scenario, a clip showed the dominant puppet receiving more Legos, while another clip showed both puppets receiving the same number.

In the other scenario, a clip again showed the puppets receiving the same number of Legos, while a different clip showed the submissive puppet receiving more.

The study found that toddlers looked an average of 7 seconds longer at the videos in which the weaker puppet received more Legos, or when the two puppets received the same number, versus when the dominant puppet received more Legos.

This indicates that the children did not expect those outcomes, Sommerville said.

The results demonstrated toddlers' expectation that a dominant individual receives more resources and that toddlers are able to adjust their thinking about resource distribution based on their perceptions of social status of the recipients, researchers said.