Have you had one of those days when there just wasn’t a good time to put your toddler down for the blessed afternoon nap?  Did his behavior and emotions look any different than they do after having a nap?  Take a moment to think about how you feel and react when you are sleep-deprived.  It gets harder to think clearly and to be in a good mood.  It’s pretty easy to feel irritable, though, right?  It’s probably not a surprise to you that toddlers would have a similar response to not getting enough sleep.  That’s exactly what the study below found, too.


While sleep studies typically focus on adults, a study in the Journal of Sleep Research by Berger and colleagues looked at 30-36 month olds.  They studied ten healthy children with no assessed sleep problems and looked at the impact of missing one nap.  Parents kept a strict sleep schedule for the toddlers for five days, at the end of which they either allowed or did not allow the daily nap.  They then repeated the same strict sleep schedule for five days and did the opposite nap arrangement (i.e., nap or no nap).

At the end of each five day period, the toddlers were observed in an emotion-related activity where they looked at pictures that typically elicited positive (e.g., baby), negative (e.g., shark), or neutral (e.g., dustpan) emotions.  They then participated in two problem-solving tasks (i.e., puzzles) with a familiar examiner, one of which was solvable and one of which was unsolvable.  These tasks took place about an hour after their typical post-nap wake-up time.

The researchers looked at displays of positive and negative emotions, as well as confusion.  Confusion, they stated, is a “knowledge emotion” that happens during times when there is low comprehension and high novelty and it can drive people to engage in a task and look for solutions. 

Just as they had guessed, the researchers found that skipping just one nap had a significant impact on the toddlers.  When they missed a nap they showed less confusion, or cognitive engagement, and more negative emotions when looking at neutral stimuli.  Missing a nap was also related to more negative displays of emotion in response to negative stimuli. 

And how about those puzzles?  After missing a nap, there was a significant decrease in positive emotions (less joy and pride) during the solvable puzzle and a significant increase in negative emotions (anxiety and worry) and decrease in confusion during the unsolvable puzzle in comparison to when they had a nap.   In other words, what may seem like not a big deal (i.e., missing one nap) looks like it led to less joyful, more anxious toddlers that couldn’t think straight enough to know when something was amiss.

The puzzle tasks are particularly interesting, as the researchers point out, for their similarity to tasks that children who attend preschool/school may encounter.  One of the first questions that I have for parents that have concerns about their child’s school performance, including the ability to stay focused, complete tasks, and regulate emotions, is how the child’s sleep is.  Not enough of it can certainly spell disaster for school performance. 

So the bottom line is pretty clear here.  Toddlers need their naps and a good night’s sleep.  And as they grow older, it is safe to say that your child will continue to need a good night’s sleep on a regular basis.  While this may sound simple, it is not always easy.  Good sleep is not a given, but doing certain things can increase the likelihood of it.  A good place to start for any child is with an established, positive bedtime routine.  For suggestions on getting started, please see Nestor’s previous post on the topic.  In the meantime, know that your child’s naptime and regular bedtime are just as important for parents as they are for the child.  We all need and deserve a break, some time to unwind, and to take care of ourselves.