Parents who are concerned about the long term effects of their child’s language delays can rest a little easier: a new study find that children who are "late talkers" do not have any more behavioral or emotional problems than other children as they grow up.

By the time the kids were 5 years old, there were no differences between the previously late talkers and children who had had normal language development.

Researchers followed 1,400 toddlers through adolescence, tracking their language skills and emotional and behavioral development. About 10% of the children in the study had language delays (scored in the bottom 15% of a test of 310 common words) at age two. The researchers did find that at the age of two there was a link between language delay and certain psychological problems like internalization (exhibiting shyness, sadness, or being less active).

But by the time the kids were 5 years old, there were no differences between the previously late talkers and children who had had normal language development. The researchers followed all of the participants until they were 17 years old, and found no lingering behavioral effects through that time period.

The team concluded that "[e]xpressive vocabulary delay at age 2 years is not in itself a risk factor for later behavioral and emotional disturbances in childhood and adolescence."

The team also underlined the fact that it was only at age two that both language and behavioral problems were seen, which could suggest a causal relationship between the variables: The "behavioral and emotional problems identified at age 2 years are attributed to the psychosocial difficulties (eg, frustration) of not being able to communicate effectively." In other words, children may be frustrated by their inability to communicate, so act out as a result. Accordingly, as language skills improve over time, behavioral problems disappear.

According to the authors, doctors and parents should likely take a "wait-and-see" approach with children who do not exhibit any significant developmental problems. Still, because "persistent language impairment" has been associated with psychological problems, more research should be done to understand all the nuances of the relationship between language and behavior. In the meantime, parents should foster their children’s language development as best they can — turning off the TV and focusing on meaningful interactions, and making sure all caretakers are on board with language development are good ways to start.

The study was carried out by researchers at the Centre for Child Health Research at the University of Western Australia, and published in the July 4, 2011 online issue of Pediatrics.