In good news to parents of late talkers, an Australian study shows a slow start on language is unlikely to have lingering effects on kids' mental health.
Researchers followed late talkers into their teens and found the kids were no more likely to be shy, depressed or aggressive than their peers as they grew up.
That means a "wait-and-see" approach may be just fine for toddlers with a language lag, as long as they develop typically in other areas, the Australian team reports in a paper published in Pediatrics.
Up to 18% affected by language delays
Between 7 and 18% of children have language delays at two years, although most catch up by the time they start school. Some research has suggested that these toddlers may face psychological problems, but whether that matters down the road has been unclear.
The new study, led by psychologist Andrew Whitehouse at the University of Western Australia in Perth, is the first to track late talkers over the long term.
The researchers studied more than 1,400 two-year-olds whose parents had filled out a language development survey, asking about the words their child would use spontaneously. A two-year-old typically says a few hundred words, but there is a lot of variation.
About one out of every 10 two-year-olds in the study was a late talker, scoring in the lowest 15% on a list of 310 common words.
Psychological problems don't persist
The slower toddlers also appeared to have more psychological problems, according to questions on a child behaviour checklist that parents answered. For instance, 13% of the late talkers had "internalising" behaviour - such as being shy, sad or under-active - compared to 8% of their earlier-talking peers.
But that difference had vanished at age five, when then parents were approached again. And it didn't reappear for as long as the kids were followed, up until age 17.
According to Whitehouse and his colleagues, that hints the reason more late talkers had behavioural problems early on is likely because they were frustrated by not being able to communicate effectively - not because there was something wrong with their brains.
Still, they say, it's important to pay attention if the kids don't catch up, because persistent language deficits have been tied to mental health problems. - (Frederik Joelving/Reuters Health, July 2011)
Child developmental stages
Child: emotions and behaviour