Parents' hesitations help toddlers learn new words

A team of cognitive scientists has good news for parents who are worried that they are setting a bad example for their children when they say "um" and "uh." A study conducted at the University of Rochester's Baby Lab shows that toddlers actually use their parents' stumbles and hesitations (technically referred to as disfluencies) to help them learn language more efficiently.

For instance, say you're walking through the zoo with your two-year-old and you are trying to teach him animal names. You point to the rhinoceros and say, "Look at the, uh, uh, rhinoceros." It turns out that as you are fumbling for the correct word, you are also sending your child a signal that you are about to teach him something new, so he should pay attention, according to the researchers.

Young kids have a lot of information to process while they listen to an adult speak, including many words that they have never heard before. If a child's brain waits until a new word is spoken and then tries to figure out what it means after the fact, it becomes a much more difficult task and the child is apt to miss what comes next, says Richard Aslin, a professor of brain and cognitive sciences at the University of Rochester and one of the study's authors.

"The more predictions a listener can make about what is being communicated, the more efficiently the listener can understand it," Aslin said.

The study, which was conducted by Celeste Kidd, a graduate student at the University of Rochester, Katherine White, a former postdoctoral fellow at Rochester who is now at the University of Waterloo, and Aslin was published online April 14 in the journal Developmental Science.

Read more here