Nine-month-old Latino babies have the same language and cognitive abilities as their white peers, but by the time they reach age 2, they lag significantly behind, according to new research from the University of California at Berkeley.

The research suggests that prekindergarten may be too late to start trying to close persistent academic achievement gaps between Latino and white students, said Bruce Fuller, the study’s lead author and professor of education and public policy at UC Berkeley.

According to Fuller, preschool could narrow the language gap by one-third, suggesting that policymakers should consider how to ramp up efforts to reach babies and toddlers earlier, especially by helping parents understand how they can help their children learn.

“Extending quality pre-K is one piece of the puzzle. But our new findings reveal how gaps in early language and preliteracy skills open up in toddlerhood, long before children enter preschool,” Fuller wrote in an e-mail.

The study, published this week in the Hispanic Journal of Behavioral Sciences, was based on a nationally representative sample of 4,550 white and Mexican-American children.

Latino students work on reading skills at the Detroit Public Schools' Academy of the Americas in Detroit. (Carlos Osorio/AP)

Researchers visited the children’s homes twice: when they were nine months old and again when they were 2 to 3 years old. On the first visit, the researchers assessed babies’ ability to manipulate simple objects, such as a rattle, and use and comprehend words; on the second visit, they assessed the toddlers’ memory, vocabulary and basic problem-solving skills.

The parents were allowed to decide whether the child would be assessed in English or Spanish.

The Berkeley team found that about 80 percent of Mexican-American toddlers grew more slowly than white toddlers, and by 2 years old were three to four months behind their white peers.

The children of immigrant mothers tended to lag further behind than the children of Mexican-American mothers who were born in this country, a difference that researchers linked in part to immigrant mothers’ weaker education.

In addition, native-born Mexican-American mothers tended to read more frequently with their children and use richer language with them.

“It appears that acculturation exposes mothers to more inventive and stimulating educational practices in the home,” Fuller wrote in an e-mail.

Latino toddlers’ cognitive abilities also tended to be higher when the mother worked outside the home and when the mother was more generous with praise and encouragement during difficult tasks.

This is the first study to establish that Latino children start out with the same abilities as their white peers and then fall behind in the first few years of life. But similar data have been published for other groups, including African-American children, and there is a growing body of evidence that academic achievement gaps begin to open before children enter formal schooling.

In 2010, the Obama administration funded the nationwide expansion of home visiting programs, which aim to improve children’s outcomes by educating parents about subjects ranging from health and domestic violence to language development and school readiness.

Congress is currently debating whether to continue investing in that program, known as the Maternal, Infant and Early Childhood Home Visiting program.