Researchers have found that parents from high socioeconomic brackets tend to talk more and with a wider vocabulary, and that may explain why their kids are also better with words. Scientists have also shown that parents who gesture more--pointing at the family dog, say, or waving--have children who gesture more, and that more gestures predicts a better vocabulary. But they didn't know how socioeconomic status played into this equation.
So psychologists Meredith Rowe and Susan Goldin-Meadow of the University of Chicago in Illinois studied 14-month-olds from 50 local families. (Gesturing starts at about 10 months.) The families had average household incomes ranging from less than $15,000 per year to more than $100,000 per year. The team went to each family's home and videotaped 90 minutes of their everyday behavior, paying particular attention to how much the primary caregiver and the child talked and gestured. Pointing at a dog, a table, and a window counted as three gestures; pointing at the table three times counted as one gesture.
As with talking, families of higher socioeconomic status tended to use more gestures. And the trend held for their children: Those belonging to families at the upper end of the socioeconomic spectrum used an average of 24 gestures in a 90-minute period versus 13 gestures for children at the lower end of the spectrum.
Those numbers translated into better vocabularies later on. When Rowe and Goldin-Meadow gave the children a standardized test more than 3 years later, those from higher- socioeconomic-status families scored an average of 117, whereas those from lower-socioeconomic-status families scored an average of 93.
Why exactly a child who gestures more would have a better vocabulary is unknown. The researchers suggest that gesturing may play a role in learning new words if it helps the child associate an object with a name. For example, when a kid points to a dog, the caregiver may help her learn by saying, "Yes, that's a dog."
The findings may have implications for intervention. Because gesturing often starts at about 10 months of age, children may display differences in their future vocabulary even before they are able to talk, Goldin-Meadow says. "It suggests that there are big-time things happening very early on in these families and that we should be intervening earlier."
Still, the researchers note that they have not shown a causal relationship between gestures and vocabulary. Wealthier, more educated parents may have children who know more words for a variety of reasons. Next, the team hopes to manipulate the amount that a parent gestures to more directly gauge the link between gestures and vocabulary.