Child psychologists and kindergarten teachers have long known that when children first show up for school, some of them speak a lot more fluently than others. Psychologists also know that children’s socioeconomic status tends to correlate with their language facility. The better off and more educated a child’s parents are, the more verbal that child tends to be by school age and vocabulary skill is a key predictor for success in school. Children from low-income families, who may often start school knowing significantly fewer words than their better-off peers, will struggle for years to make up that ground.
Previous studies have shown that wealthier, educated parents talk to their young children more, using more complex vocabulary and syntax, than parents of lesser means. And these differences may help explain why richer kids start school with richer vocabularies. But what goes on before children can talk, during that phase familiar to any parent when communication takes the form of pointing, waving, grabbing and other kinds of baby sign language Do well-off parents also gesture more to their kids
Indeed they do, say psychologists Susan Goldin-Meadow and Meredith Rowe of the University of Chicago, who published a study in the Feb. 13 issue of Science. The researchers found that at 14 months of age, babies already showed a wide range of “speaking” ability through gestures, and that those differences were correlated with their socioeconomic background and how frequently their parents used gestures to communicate. High-income, better-educated parents gestured more frequently to their children to convey meaning and new concepts, and in turn, their kids gestured more to them. When researchers tested the same children at 54 months of age, those early gesturers turned out to have better vocabulary ability than other students.
“At 14 months, you can’t see a difference with their speech, but you can already see a difference with their gestures,” says Goldin-Meadow, a leading expert on gesture. “And children’s gestures can be traced back to parents’ gestures.”
Goldin-Meadow and Rowe’s study involved children from 50 Chicago-area families of various ethnic and socioeconomic backgrounds. Annual incomes ranged from less than $15,000 to more than $100,000, and parents’ educational level ranged from high school dropout to advanced degree. The researchers videotaped each child at 14 months with his or her primary caregiver for 90 minutes while the pair engaged in everyday activities. Those tapes were then transcribed all speech and gestures seen during the 90 minutes were noted and recorded in code.
Researchers were interested less in the number of gestures a child or parent made than in their variety for example, pointing at a doll 10 times would count as only one gesture, but pointing at a doll and then a bed might count as two. During the 90-minute session, 14-month-olds from well-off families used an average of 24 meaningfully different gestures, researchers found, while children from lower-income families used an average of just 13.
“As early as 14 months of age, children in different socioeconomic-status groups may be socialized to communicate more or fewer meanings via gesture,” the authors wrote. And those early differences in gestures may help predict the later disparities in vocabulary ability when children show up for school. The current study found that at 54 months old, children from higher-income families understood about 117 words on a comprehension test, compared with 93 for children from lower-income families.
Although Goldin-Meadow is quick to point out that the study shows only an association, not a causation, among socioeconomic status, gestures and vocabulary ability, “we do think there is something going on here,” she says. “When parents gesture around their children, the kids might be picking up the gestures and doing it themselves.”
Here’s how: at 14 months of age, pointing toward an object is the way most kids use gestures. If a parent responds to that gesture by verbally identifying the object by saying, “That’s a doll,” for example children get a head start on growing their nascent vocabularies. “That’s a teachable moment, and mothers are teaching the kids the word for an object,” says Goldin-Meadow. She also believes that lively gesturing could allow kids to better understand new concepts simply by giving them a visceral way to express them.
That last theory offers the possibility that teachers may be able to use gesture to help school-age kids solidify old ideas and learn new ones. In separate research, Goldin-Meadow found that when children were asked to solve and explain a series of math problems, those who were asked to gesture while they did so were more likely to learn new problem-solving strategies and perform better on future math problems than were kids who did not use gestures. Goldin-Meadow believes that prompting children to gesture gives them the ability to express ideas they had never been able to express before. “I’d recommend teachers encourage their kids to gesture, because it makes them more receptive to teaching,” she says. “It allows teachers to have a better understanding of what their kids are understanding.”
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