Learning new words can be a challenge for any preschooler, but kids who take naps may have an advantage when it comes to developing language skills, a new study suggests.
Researchers assessed 39 youngsters who were all 3 years old and found those who napped after learning new verbs had a better understanding of the words 24 hours later.
"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 sleep, which is one of the deepest forms of sleep," said study co-author Rebecca Gomez. She is principal investigator of the University of Arizona's Child Cognition Lab.
"What's really important about this phase is that essentially what the brain is doing is replaying memories during sleep, so those brain rhythms that occur during slow-wave sleep ... are actually reactivating those patterns -- those memories -- and replaying them and strengthening them," Gomez said in a university news release.
Despite the findings, parents shouldn't fret if they can't get their preschooler to nap during the day, the researchers noted. The most important thing is total amount of sleep. Preschoolers should get 10 to 12 hours of sleep in a 24-hour period.
"We know that when children don't get enough sleep it can have long-term consequences," including poor performance on mental skill tests, Gomez said.
If children don't get enough sleep at night, it's a good idea to encourage them to nap during the day, the study authors suggested.
"It's important to create opportunities for children to nap -- to have a regular time in their schedule that they could do that," Gomez said.
In the study, the investigators chose to test the children on how well they learned and understood verbs rather than nouns because action words are typically more difficult to grasp than names, such as "Mommy" or "doggie," which are often the first words kids learn.
The findings were published recently in the journal Child Development.