Experimenting on Babies: 5 Surprising Studies

Oct. 7, 2011— -- Teaching the concepts of sharing and fairness is the goal of every kindergarten lesson plan, but babies as young as 15 months may have already picked up these complex social skills, according to new research from the University of Washington.

"Our research shows that children become sensitized to the idea of fairness much earlier in life than previously thought. This concept of fairness also seems to influence an infant's tendency to act altruistically when given the option to share with a stranger," says Jessica Sommerville, a University of Washington associate professor of psychology who led the study.

In the study, experimenters capitalized on the fact that babies are known to stare longer at things that surprise them or challenge their expectations. The researchers had infants observe different scenarios in which an experimenter divided up crackers or a pitcher of milk among two people. The babies tended to look longer at the scenario when the treats were divided unequally (and hence "unfairly"), suggesting they were surprised by this outcome -- they expected that food should be divvied up equally.

Next, researchers gave the same infants two toys to play with and noted which one each baby preferred. Then they had an experimenter, who was a stranger to the infant, go up to them and ask for one of the toys. Babies who had stared longer at the "unfair" treat distribution were more likely to be "altruistic sharers," meaning that they readily gave their preferred toy to the stranger when asked. Infants who gave their less preferred toy were deemed "selfish sharers." These infants were significantly less likely to have stared longer at the unfair treat distribution.

"This research shows scientifically, what we would intuitively think -- that a stronger sensitivity to fairness is linked with the ability to act altruistically," says Sommerville.

The study was published Friday in the journal PLoS ONE.

Baby Labs -- Running Experiments on Infants

The concept of a baby lab may elicit images of little tykes hooked up to electrodes and beeping machines, but in reality, most developmental psychology labs look more like a day care center. Usually babies are brought in with their mothers, and, as far as they know, the infant gets to play with a few toys and watch a few videos.

By observing infant behavior in a number of play settings and by tracking how they react to different stimuli and video scenarios, developmental psychologists can piece together the inner workings of the most powerful learning machine ever invented – the infant mind.

Here are some of the most fascinating findings derived from "baby labs" in the past few years.

Babies Like the Good Guy

Somewhere between the first six and 10 months of life, babies learn to root for the good guy, according to a 2007 study from Yale University.

Researchers showed 10-month-olds a few video vignettes in which one toy is trying to get up a hill. In one scenario, a different toy helps the another toy up, in another vignette, yet another toy hinders it, pushing the original toy back down the hill. After watching these vignettes, babies were much more likely to reach for the helper toy to play with when given a choice between the helper toy or the hinderer toy.

"These findings constitute evidence that preverbal infants assess individuals on the basis of their behavior toward others. This capacity may serve as the foundation for moral thought and action, and its early developmental emergence supports the view that social evaluation is a biological adaptation," the study said.

Talk Baby to Me

We can't help it -- we see an infant and all of a sudden we're speaking in high-pitched, sing-song tones, cooing and babbling to the little bundle of joy. Though this baby talk may get on the nerves of those around us, babies love it and will pay more attention if you use it.

A 2011 Harvard study showed that 5-month-old infants look at and pay more attention to adults who use baby talk when speaking to them. Even after the talking is done, the infants had learned to prefer those adults who used baby talk. Researchers believe that babies use baby talk as a social cue: "This cue allows infants to focus their attention on individuals who are more likely to talk to them, and attend to them, and thus provide optimal care and opportunity for learning," says Adena Schachner, a Harvard psychologist and lead author of the study.

Now, You're Speaking My Language

Another study from the Harvard baby lab by psychologist Elizabeth Spelke found that by 10 months old, infants learn to prefer the people and things discussed in their own language. When researchers had two adults introduce two different toys, one in the infants native tongue, another in a foreign language, the babies looked longer at the adult speaking their language. When given a choice of toys to play with, the babies also tended to play with the toy they had seen the native-speaking adult hold.

This study suggests how strong our natural tendency is to prefer our "in-group" – those individuals who share our language, culture and as some infant studies have found, our physical appearance and skin color. Researchers believe these tendencies manifest themselves again in how children learn how to fit in to their social group as they grow older. When a similar experiment was done with toddlers, the toddlers were more likely to give a toy to the adult who spoke their language when given the option to give a "gift" to one of the two adults in the videos.

Babies Appreciate an Emotive Tune

As early as 9 months, infants can tell the difference between a happy song and a sad song, according to a 2008 study from Brigham Young University. Before infants learn to understand language, they use tone and emotion in the voice to derive meaning. This sense seems to carry over into recognizing the tone of musical selections, according to this research.

Researchers played three excerpts of happy instrumental music to 9-months-olds, repeating the excerpts until the infants appeared bored and looked away. If the researchers then played new happy songs, the infants did not regain interest, but when sad instrumental excerpts were played, the infants perked up, recognizing that they these songs were novel and different from the past selections.

In a news statement at the time, Brigham Young music professor Susan Kenney weighed in on this finding: "The happy songs were all in major keys with fairly short phrases or motives that repeated. Four of the sad songs were in minor keys, and all had a slower beat and long melodic rhythms," she said.

That infants can notice those difference so early in life is "fascinating," she said.