They've barely opened their eyes, but newborn babies already seem to prefer nice behaviours.
New research reveals that infants just five days old can tell the difference between two distinct forms of prosocial and antisocial behaviour—and they prefer the prosocial. This suggests that some parts of how humans understand and evaluate the social world may be built into the brain from birth.
"These babies have almost no experience with the social world, and yet they're already picking up on friendly versus unfriendly interactions, on helping versus hindering. That could be telling us something really important about human nature," said Dr. Kiley Hamlin, a professor in the department of psychology at the University of British Columbia who co-led the study with Dr. Alessandra Geraci, assistant professor in the department of educational sciences at the University of Catania (Italy). Luca Surian (University of Trento) and Lucia Gabriella Tina (ARNAS Garibaldi Hospital) were their co-authors.
Watching for acts of kindness
Researchers showed a total of 90 newborns sets of simple animated videos. In one, a ball struggled to climb a hill. Another ball helped push it up. In a second video, playing right next to the first, the second ball pushed the climber down the hill, preventing it from reaching the top. Infants' eyes lingered longer on the helping scenario.
In another set of videos, one ball moved toward another as if trying to get close or say hello. In the other video, the ball moved away, like it was avoiding the other. Again, the newborns spent more time watching the friendly, approaching action.
To make sure the babies weren't just reacting to movement, researchers showed control videos where balls were simply in motion with no implied social interaction. Babies didn't show a preference for one video or the other.
"This tells us that babies aren't just reacting to distinct patterns of motion," Dr. Hamlin said. "They seem to be responding to the social meaning behind those motions."
But can newborns even see well enough for this? Newborns have a reputation for poor vision, which Dr. Hamlin said is commonly misunderstood.
"Newborns don't see well far away, but they can see pretty well up close—and motion captures their attention," she said. "Our animations were presented right in front of babies' faces, in high contrast, with simple motions that repeated over and over. That's exactly the kind of thing newborns are good at detecting."
A built-in social sense
This study builds on earlier work by Dr. Hamlin and others showing that older infants—around six to 10 months—prefer helpful characters. But this is the first demonstration in days-old babies, suggesting that these preferences aren't learned.
"Five-day-old babies are asleep a lot of the time, and likely haven't observed prosocial or antisocial behaviour. Even if they had, their poor distance vision means they probably couldn't process the event unless it happened immediately in front of their face. Yet they still prefer to watch prosocial interactions over antisocial ones," Dr. Hamlin said. "That makes it very unlikely they've learned this entirely from experience."
What it means
These findings, published in Nature Communications, add weight to the idea that humans may be born with a basic sense of social goodness. That doesn't mean babies are born knowing right from wrong in the way adults do—but the roots of social evaluation, and even moral understanding, may begin with these basic social preferences.
"There's been a lot of debate about whether morality is learned or innate," said Hamlin. "This study doesn't settle that debate, but it certainly pushes the needle toward the idea that some parts of our moral sense are built in."
Even before they can smile, speak or sit up, babies are already watching the world—and most are rooting for the good guys.
