Your Preschooler's Brain May Determine When They Give Up Naps

As a child gets older and starts to leave the baby stages behind, many parents begin wondering when their preschooler should drop their nap. A new study by University of Massachusetts-Amherst sleep scientist Rebecca Spencer, PhD, and Tracy Riggins, PhD, a University of Maryland child psychologist specializing in memory development, shows us it’s not about the number, but rather the child’s brain development.

“At some point, we transition out of napping,” Dr. Spencer says. “And so our overarching question is ‘what determines physiologically, biologically and neurologically when a child should be done napping? And our answer here is it's related to the brain and the development of the brain.”

Dr. Spencer's previous work focused mainly on adults and sleep, but then she and her team realized preschools would make a great controlled environment to understand more about sleep and young children. She became interested in what happens in a preschooler’s brain when napping.

The research team looked at different preschools' philosophies around nap time and found that it was not uniform across the board. Some schools had dedicated nap time while others did not see the need.

“We were observing the preschool classrooms and how mixed the opportunities for sleep were. Often we would hear things like ‘kids don't need to nap’ or they don't really support the sleep environment,” Dr. Spencer explains. “For people to actively question whether these kids should be napping was really surprising to us and became a question of its own.”

How Napping Affects a Preschooler's Brain

Dr. Spencer’s study primarily focused on how napping affects a preschooler’s memory, particularly declarative memory. That's when a child is actively learning something, for example when they are in a class at school. Naps were shown to give an immediate benefit to this kind of memory. Spencer and her team also saw that naps were important in other areas of a child’s well-being.

“We see that naps also help things like emotional learning,” Dr. Spencer explains. “We've kind of seen now that naps are beneficial across the board for a lot of different tasks. But some tasks are benefited by even further sleep overnight.”

A child’s emotional reactivity was also heightened if they were deprived of naps, Dr. Spencer adds. She explains that if a kid is a habitual napper and they do not sleep during the day, they are really distracted by emotional stimuli.

“[Nap-deprived children] are going to be hyper-attentive to that kid who's acting up in the corner or being silly or being grumpy, and they're going to be really reactive to that,” Dr. Spencer says. “[But] if they nap, they can control that change of their attention, and how distracted they are by these different kinds of emotional things in their environment.”

After conducting several different types of tests, Dr. Spencer found that overall, naps are consistently valuable and have a vast array of benefits, even as kids get older.

What Happens in the Brain When Naps Stop?

Once children enter preschool, their napping environment may change. It can be difficult for some parents to determine whether it’s okay for their children to stop napping or whether there are other reasons for nap refusal.

"[Make sure] it's not about some need," Aliza Pressman, PhD says of the reasons preschoolers may be averse to napping. "They may have to connect with a grown-up emotionally or they feel like they're missing out."

Dr. Spencer and the nap researching team conducted their study in two different ways to understand when and why that transition away from napping happens. One of the ways was to give kids a memory task and have them learn something in the morning. Then, they’d either get them to nap or keep them awake during nap time to see how their brains were affected.

The other tool the researchers used was having kids undergo an MRI to actually see their brain development measured against their napping routines to find a correlation. What Dr. Spencer found was that napping was actually connected to the brain’s hippocampus, which is a part of the brain that controls memory.

“What we think happens is that the hippocampus develops so that it can hold more information," Dr. Spencer says. When children are able to transition out of napping, that's when the hippocampus is able to hold that information throughout the day.

From the findings, Dr. Spencer concludes that not only are naps important for children but that their transition away from them is connected to how developed their hippocampus is.

“When the hippocampus is inefficient, it’s like having a small bucket,” Dr. Spencer says. “Your bucket is going to fill up faster and overflow, and some memories will spill out and be forgotten. That’s what we think happens with the kids that are still napping. Their hippocampus is less mature, and they need to empty that bucket more frequently.”

Why Do Preschoolers Need Naps?

Children who are habitual nappers will continue to need naps even as they enter preschool. Dr. Pressman explains that it can be hard to tell when their brain has signaled they no longer need routine naps. She adds that while parents won’t necessarily know when their child’s hippocampus has developed, there are steps they can take to still encourage periods of rest to support their child’s needs.

"I wouldn't want parents to panic if their child is naturally and appropriately at the point of their brain development that they're finished with that nap time," says Dr. Pressman. "I just want to distinguish between the kids who need it because they're not getting good nighttime sleep and the kids who need it because they get good nighttime sleep and their brains still need daytime sleep for maturation."

Dr. Pressman also emphasizes that just because some children may begin to refuse nap time doesn’t necessarily mean that they don’t need them. It could just be that kids need a little more downtime.

"Preschoolers' brains need more development that is going to prepare them to be able to retain memory without napping," Pressman says. "Some are going to be ready at age 3 to retain the information they get throughout the day without taking a nap, while others will need a nap all the way up to kindergarten to be able to retain information without having that time to sleep and regenerate."

What if My Child's Preschool Doesn't Have Naptime?

Ideally, it’s best for children to be in environments where they will have consistent nap opportunities, but that’s not always the case. Dr. Spencer says in an optimal situation, parents would take nap time practices into consideration when choosing a preschool for their child.

“Not everybody has a choice and what can they do? I would say that if it's a center where the kid comes home by three o'clock in the afternoon, there's still an opportunity for them to at least have that downtime and possibly nap between that time and dinner time,” Dr. Spencer adds. “Just as long as those naps don't get too late because if they nap too late, then it's going to be harder to fall asleep at night.”

Another suggestion Dr. Spencer offers is to consider advocating for nap time at preschools if they don’t have it. If that doesn’t work, both Dr. Pressman and Dr. Spencer propose making sure kids get even more sleep overnight if they aren’t getting it at school. 

"The first thing you would do if they're dropping the nap is to still offer the quiet time and then do an earlier bedtime," says Dr. Pressman. "The solution is going to be making a much earlier bedtime at night. So as early as 5:45 p.m. for kids who really need a nap. And they should be able to sleep sometimes 13 hours because they're just really needing that extra sleep."

Above all, Dr. Pressman says, parents and preschools alike should understand the value of continued nap time or downtime.

"We do get so fixated on all of the things that we think our 3 to 5-year-olds can learn if they're not, 'wasting time resting,'" Pressman says. "And so this is just a reminder that for the kids who need it, they're going to learn more by taking the nap."