Parents should make time for their preschoolers to nap since a recent study suggests it is crucial to language learning.
Researchers from the University of Arizona studied verb learning in 3-year-olds and found those who napped after learning new verbs had a better understanding of the words when tested 24 hours later. The findings, which will be published in the journal Child Development, suggest that parents may want to consider maintaining regular nap times for preschoolers, who are at an age in which naps have a tendency to dwindle, says lead study author and UA alumna Michelle Sandoval.
For the study, 39 3-year-olds were randomly assigned to either nap for at least 30 minutes after learning a new verb or stay awake after learning the verb. Experimenters taught the children two made-up verbs and showed them a video with two different actors performing actions corresponding with the verbs.
Twenty-four hours later, the children were shown videos with different actors performing the same actions and were asked to identify which action the actors were performing. The children who had napped within about an hour of learning the verbs performed better than those who stayed awake for at least five hours after learning the verb.
Different actors were used in the testing to allow researchers to measure how well children “generalized” the new verbs, meaning they were able to recognize them even when performed in a different context by different people.
“You have to be able to generalize words to be able to use them productively in language,” Sandoval says. “Regardless of typical napping behavior … children who were asked to nap after learning were the ones who generalized, and those who stayed awake were not able to generalize 24 hours later.”
Researchers think the learning benefit of napping could come from what is known as slow-wave sleep, according to a release on the study.
“There’s a lot of evidence that different phases of sleep contribute to memory consolidation, and one of the really important phases is slow-wave, which is one of the deepest forms of sleep,” says study co-author Rebecca Gómez.
Parents should not, however, fret if they can’t get their preschooler to nap during the day, since there is a lot of variability in children’s sleep behaviors at that age, Gómez, says.
The most important thing is total amount of sleep, she says. Preschool-age children should get between 10 and 12 hours of sleep in a 24-hour period, whether it’s all at night or a combination of nighttime sleep and napping, she says.
“We know that when children don’t get enough sleep it can have long-term consequences,” including deficits on cognitive tests, Gómez says.
By Betsy Stein