Healthy Sleep Habits, Happy Child
Subjective Blindness to Sleepiness
February 8, 2021

Found in age groups

Healthy Sleep Habits, Happy Child

5th Edition: 
A Step-by-Step Program for a Good Night's Sleep

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Healthy Sleep Habits, Happy Child

5th Edition: 
Chapter 1 (only 16 pages!) outlines everything you need to know about your child's sleep.

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A Healthy Child Needs a Healthy Brain, A Healthy Brain Needs Healthy Sleep

Sleep is serious business. If you have not already done so, please read Blog Posts 1 through 5 that describe how sleep is important and beneficial, from the point of view of the United States of America Department of the Army. A major point, emphasized by the Army, is that more sleep produces more benefits for Soldiers. Also, more sleep produces more benefits for children. Even small amounts of extra sleep help (Blog Post 6). At every age!

Another point made by the army is: “Most Soldiers who regularly obtain a little less sleep every 24 hours pay a price: they unwittingly [Subjective blindness to sleepiness] but steadily accrue a significant sleep debt, characterized by increasingly suboptimal alertness, reduced mental sharpness, and an impaired ability to recover from stress.  These Soldiers typically believe they are fine [Subjective blindness to sleepiness] and may perform most basic duties adequately.  From an objective standpoint, their alertness and mental acuity is significantly (and invariably) impaired.” And “Leaders [Parents] evaluate a Soldier’s [Child’s] performance, since insufficient sleep impairs the ability to self-assess [Subjective blindness to sleepiness]. As a rule, sleep-deprived Soldiers [Children] will overestimate their own capabilities.” And “Although chronically sleep-restricted Soldiers [Children and Parents] do become accustomed to a reduced level of alertness, which they think is normal [Subjective blindness to sleepiness] objective assessments to reveal deficits show that there is no evidence of habituation or adaptation to sleep loss.”

The Army is clear about who is in charge: “Planning for sleep is a leader [Parent] competency”

Blog 13Subjective Blindness to Sleepiness


When we are often mildly or moderately sleepy, we might not sense that we are short on sleep or appreciate the consequences of not being optimally alert. In other words, we tend to be subjectively blind to our own sense of sleepiness or sleep deficits. One study in adults who were experimentally sleep deprived showed the expected decreases in performance, but they lacked subjective feelings of sleepiness. The authors wrote, “that those who are chronically sleep deprived may no longer be capable of reliably appraising their own sleepiness. This may explain why sleep restriction is widely practiced: People have the subjective impression that they have adapted to it because they don’t feel particularly sleepy.” Also, an adult, short on sleep, feeling sleepy, is more likely to say, “I feel tired”, which suggests having performed effortful work, (which might imply being productive, which is good) instead of saying “I feel sleepy” which might suggest that he lacks energy or stamina (a sign of weakness, which is bad). 

If parents lack self-awareness about their own sleep loss, then it should come as no surprise that they might fail to appreciate subtle harmful effects of sleep loss in their children. This is such an important point; I wish to restate it: It is possible that some parents are so unaware of how impaired they are by their own sleep deprivation that they are unable to appreciate the extent to which sleep deprivation is harming their child. I suspect that this explains why otherwise observant and loving parents (who are nevertheless short on sleep themselves) allow their child to become sleep deprived, with all of its attendant problems. And if the children are too often mildly short on sleep, they themselves might not develop a strong sense of how different it feels to be completely well rested versus mildly sleepy.


  1. We have a 18 month old who puts herself to sleep by herself but is taking HOURS to fall asleep at night (she is generally happy in her crib). This results in 10 hours of sleep and she wakes up not acting refreshed. She is tired and grumpy in the morning before her nap and much happier in the afternoons. We’ve tried altering her schedule in different ways but can’t seem to help her want more sleep. Is she just a low sleep need child? Or do you have a schedule suggestion (we follow your “loose” schedule in your book!) her rough schedule is up between 8 and 8:30, naps around 1 or 1:30 or slightly earlier if acting tired (naps for 2-3 hours) and then is in bed at 7:30 or 8 pm but takes a while to fall asleep. If she has a short nap (we traveled the other day for 8 hours and she only napped 45 minutes) we do an early bedtime! We’ve also tried an early bedtime in general and she just rolls around in her bed longer! Any schedule recommendations? Or is she just always going to sleep less? Our oldest is a high sleep needs so this is new to me! Thank you!

    1. Please read the section in my book and my Blog Posts on the topic of circadian rhythms to understand why her current sleep schedule is not in synchrony with her brain’s sleep needs. To shift her entire schedule earlier, you start by controlling the wake-up time as described on page 295.

  2. Ok! Do you find that some kids are sensitive that the 1 hour difference (7 am vs 8 am wake up ) makes a big difference? Thank you!

  3. Also, on page 505 of the book edition I have it mentions how naps are a substitute for nighttime sleep! But if bedtime is late and naps are long, how do you recommend correcting? I know you don’t recommend waking from naps! On the page for 4-12 months you have a sample schedule—do you have a suggested schedule for a 18 month old? If wake time is 7 am when is nap? It says between starting at noon-2, so is that still what you recommend? Thank you so much!

    1. Q: “But if bedtime is late and naps are long, how do you recommend correcting?”
      A: Control the wake up time means you wake her at 6-7am to impose an age-appropriate sleep schedule.

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