Living in the San Francisco Bay Area for the past few years, I’ve gotten used to lots of things that would probably seem strange in other cities. Commuting on a unicycle? Sure. Rampant midday nudity? Everywhere. Vegan dinner fundraiser for your Burning Man art car? Of course. So I hardly bat an eye when a 4-year-old says, “My favorite food is edamame.”
As a developmental psychologist, I test children to learn basic facts about kids, such as how they learn language, navigate social interactions, and gain knowledge. These things seem like they should work about the same way for any young human. But there is growing evidence that the timing and efficiency with which children learn these general skills vary a lot based on experience. A huge amount of a child’s early life experience is determined by the family’s socioeconomic status—how wealthy and educated the child’s parents are. The edamame-loving professors’ kids I’ve been testing are unlikely to be representative of an average child, or even an average American child.
There’s a term to describe the types of people who participate in most social science studies: WEIRD. They are weird in the sense that they are unusual compared with most of the world’s population, but WEIRD is also an acronym describing the white, educated, industrialized, rich, and democratic culture they come from. A trio of psychology professors coined this term in a 2010 paper, pointing out that fields studying human behavior often use participants who are “Western, and more specifically American, undergraduates.”
The WEIRD issue has been talked about in psychology for many years, but there’s been little progress in addressing it. The problem is arguably even worse in developmental psychology than in other subfields. While many social science researchers recruit participants from a pool of hundreds of undergrads who must complete studies for course credit, there are no comparably large pools of children to test.
My lab mates and I recruit kids by sending mass mailings to addresses we get from state birth records, and interested parents call, email, or sign up online for an appointment. We also get a good number of participants who are friends of previous participants. Parents visit our lab at the University of California at Berkeley campus during the workweek. We don’t keep demographic records about our participants or their families, but a lot of cues suggest they’re WEIRD: their cars, iPads, fancy strollers, clothes, and the parents’ small talk about their education (“Oh, I went to Berkeley for undergrad!”). People who have the time and job flexibility to bring their kids to a lab in the middle of the workday tend to be fairly well off.
Another place we find children to test is the university’s preschools, where the kids are even WEIRDer than those who visit our lab. (The edamame kid went to preschool here.) Monthly tuition costs between $1,500 and $2,000, and the parents are highly educated, university-affiliated faculty, staff, researchers, or students. These kids know the drill with grad students’ studies: When a new person comes to class and asks if you want to “play a game,” that person is a researcher. While other children play “House” or “Doctor,” these Berkeley kids have been known to play a game called “Research.” One child holds a clipboard and asks other children to “play a game” while the child observes them and pretends to jot down notes. Some of these children have told me about their international travels, and several of the 3-year-olds have told me they can read.
Stanford University psychology professor Anne Fernald recognized the same WEIRD bias in the families that participate in her studies. Stanford’s campus is in the heart of Silicon Valley; tech giants Google and Facebook are less than five miles away. Her lab’s testing pool included some of the wealthiest and most highly educated people in the United States.
Fernald and her colleagues tried to recruit a more diverse sample for their studies but had little success. She suspects a combination of factors prevented less affluent families from visiting the lab. “The university was an alien place,” she says. “It’s intimidating, it’s costly, you need to find parking, you don’t know English, you don’t have the nanny at home to take care of the other child.” Fernald added that many of the non-English-speaking families in the area are undocumented and may have been hesitant to participate in any university programs that could expose their status.
In 2006, the lab decided that instead of asking less affluent families to come to it, the lab needed to go to them. Fernald rented a five-bedroom house in an East Palo Alto neighborhood where the average annual income is less than $25,000 and only a few parents have more than a high school education.
A postdoc, Nereyda Hurtado, lived in the house full time so that she would become a part of the community. Things were slow going while the neighbors tried to figure out what the strange research house was all about—did the people there care about immigration status? Were there doctors who could help? (Hurtado and other researchers did give parents information about agencies to contact for help with health or social service issues.) “Gradually, word spread that it was a safe place to come,” Fernald said. “We became a trusted resource in the neighborhood and soon, people were asking if they could participate.”
At the house, 18-, 24-, and 30-month-old children were tested on a task called “looking while listening.” It measures infants’ word processing skills in real time, and it’s beautifully simple. Children are seated in front of two pictures—say, a dog and a baby—and are asked to find one of the items: “Where’s the dog?” Researchers time how long it takes children to look toward the appropriate picture. Faster looks indicate faster cognitive processing, and quickness is correlated with positive long-term outcomes, such as better scores on third-grade standardized tests.