What is normal sleep for infants and toddlers?
If you’re having trouble with getting your baby to sleep through the night or just preparing for a new baby in your life, it’s important to understand normal sleep for infants and toddlers.
Difference Between REM and NREM Sleep
Everyone cycles back and forth between periods of rapid eye movement (REM) sleep and non-REM (or NREM) sleep.
When adults first fall asleep, they transition into a light NREM sleep which is known as N1. In this stage, bodily functions start to slow down but you can still be easily awakened.
N1 is followed by N2 in which your body becomes even more relaxed. Adults spend most of their total sleep time in the N2 stage.
N3 is a period of deep sleep. This is also sometimes called “slow-wave sleep” because of the type of brain waves seen on EEG during this sleep period. The brain is less responsive to external stimuli and it is more difficult to wake up in this stage.
REM sleep follows NREM sleep. Most dreaming occurs during REM sleep. In a normal eight hour period of sleep, REM sleep will occur about 4-5 times. Each period of REM sleep gets progressively longer as the night goes on. The total sleep cycle for an adult can vary in length from 70 to 120 minutes.
Imaging of the brain during sleep has shown that during NREM sleep, blood flow throughout the brain decreases.
During REM sleep, blood flow increases to certain areas of the brain.
On EEG, while brain waves slow down progressively through the NREM stages, REM sleep is characterized by an active brain wave pattern somewhat similar to wakefulness. The body stays still, however, as most motor nerve impulses are blocked and the muscles remain relaxed.
About 50 percent or more of an infant’s total sleep is spent in REM sleep. In comparison, toddlers spend about one-third of their total sleep time in REM sleep. In older children and adults, this decreases to about 20 to 25 percent.
What is Different About Infant Sleep
Babies go through the same sleep cycles as adults but they are shorter in length. Their sleep patterns reflect their biological needs.
Normal sleep for infants include the following:
- Long sleep duration (about 16-18 hours in a 24 hour period for the healthy, full-term newborn).
- REM sleep occurs at sleep onset. Instead of falling asleep into the N1 stage like adults, a newborn will fall right into REM sleep. This will last until about 3 months when they begin to transition to N1 when falling asleep like adults do.
- NREM cycle is much shorter in duration than older children and adults.
- An infant’s NREM to REM sleep cycle lasts about 45–60 minutes.
- Due to the shorter timeframe of their sleep cycles, infants often wake more frequently.
- Unlike adults, the blockage of motor impulses in babies while sleeping is not fully developed. Consequently, during REM sleep, infants will experience muscle twitches, jerks, kicks that are sometimes strong enough to wake them up.
As a baby’s central nervous system matures, there is a decrease in total sleep time, a decrease in the proportion of REM sleep, and a lengthening of the REM-NREM cycle. All of these changes will happen gradually.
Recommended Sleep Times for Children
The following recommendations were made by the American Academy of Sleep Medicine (AASM) and endorsed by the American Academy of Pediatrics. The one exception is that the AASM does not provide recommendations for infants younger than four months. This is due to the fact that there is a wide range of normal variation in sleep duration and patterns for babies this young. Premature babies will sleep more than a full-term infant in the early months as well.
|Age Group||Recommended Sleep Times|
|0 to 3 months||about 14 to 18 total hours|
|4 to 12 months||12 to 16 total hours|
|1 to 2 years||11 to 14 total hours|
|3 to 5 years||10 to 13 total hours|
|6 to 12 years||9 to 12 hours|
|13 to 18 years||8 to 10 hours|
These sleep times are recommended for optimal health, daytime functioning and development for each age group.
Importance of Sleep on Development
Both NREM and REM sleep play a role in the growth and development of the central nervous system.
Studies have shown that inadequate sleep can contribute to cognitive and behavioral issues, decreased daytime alertness, and problems with emotional regulation.
Children with poor quality of sleep may experience hyperactivity, irritability, anxiety, and aggressive behavior. In older children, insufficient sleep can affect a child’s ability to concentrate and contribute to poor academic performance.
Sleep disturbances that start when children are babies can continue into later childhood.
To prevent the consequences of poor sleep as children get older, it’s important to introduce them to healthy sleep practices in the infant and toddler stage.
Healthy Sleep Practices
- Have a consistent bedtime.
- Bedtime and morning wake time should be the same (within one hour at least) on workdays and weekends or your days off.
- Create a consistent bedtime routine.
- Keep the hour before bedtime a quiet time. Avoid high-energy and stimulating activities, including watching television.
- Keep the bedroom quiet and dark. Use a low light nightlight if needed.
- Allow your child to spend time outside every day when possible.
- Try not to use the bedroom for time-out or punishment to avoid negative associations with their room/bedtime.
How is your baby sleeping? What is your biggest concern with your infant or toddler’s sleep? Let me know in the comments!
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Wise, M. S. & Glaze, D. G. Sleep physiology in children. Last updated 3/21/19. https://www.uptodate.com
Owens, J.A. Cognitive and behavioral consequences of sleep disorders in children. Last updated 10/29/18. https://www.uptodate.com
Bollu, P. C. Normal sleep, sleep physiology, and sleep deprivation. Updated 11/5/19. https://emedicine.medscape.com/article/1188226-overview#a1