Scientific data now appear to support something parents of young children have long known intuitively: A good night’s sleep is important, but naps are also necessary for preschoolers to be at their best.
That’s one takeaway from a University of Massachusetts Amherst study published Wednesday in the scholarly journal Scientific Reports.
The evidence suggests there are developmental benefits — both cognitive and emotional — to getting preschoolers to lie down after lunch, even if they balk at the idea, researchers said Tuesday.
“The big thing is that the preschool age . . . is the time that children start to wean off napping,” said Lauri Kurdziel, an assistant professor of psychology at Merrimack College in North Andover who conducted the research as a doctoral student. “The big question for parents is when is the right time.”
Kurdziel noted that getting preschoolers to nap can be a challenge because children in that age range are learning that they can push against boundaries.
By showing images that were associated with emotions to 49 3-, 4-, and 5-year-olds, her team found that the tykes’ memories improved when they both napped during the day and slept well that night, she said. The preschoolers in the study, she said, sometimes could remember images the next day that they hadn’t recalled shortly after their naps.
That response suggests that children’s brains continue processing their daily experiences during both periods of sleep, Kurdziel said.
Rebecca Spencer, an associate professor in the UMass Department of Psychological and Brain Sciences who led the study, said sleep is like a valve releasing pressure in growing, learning brains.
“I think of it as this — kids have lots of emotional experiences (by their perception) — dad made them put their shoes on, mom wouldn’t let them have a cookie, someone took the ball they wanted to play with,” Spencer said in an e-mail.
“So this builds up and they get more grumpy across the day, particularly if they don’t nap,” she continued. “Our data suggests that the nap begins to process these emotional experiences, reducing their emotional baggage, so to speak. But when supplemented by overnight sleep, in combination, there’s even greater emotion processing.”
Kurdziel said it can be easy to persuade ourselves that we — and our kids — can make up for lost sleep at a later time, but “that’s not been shown to be true for adults and that’s not shown to be true for children.” Developing brains need regular naps and nightly bedtimes “to get the ultimate benefits of that sleep.”
“Everybody knows what a napless kid looks like,” she said. “They’re giddy or they’re grumpy or they’re throwing a temper tantrum. . . . It’ll just be happier and healthier for everybody if they’re following a consistent schedule.”