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In the womb, babies spend about 95% of their time asleep. And as soon as they make their entrance into the world, they’ll still spend the majority of their time sleeping—the transition from the womb to the real world is overwhelming and exhausting for your little one.
Not to mention, their bodies are in a state of rapid development—especially their brains. While they’re snoozing, memories are being stored, synapses are forming, brain tissue is developing, connections are established, energy is replenished…and a whole lot more.
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It’s hard to imagine all that going on inside of this tiny person—but it’s happening—and it’s setting them up for proper growth and development as they get older. In fact, your baby’s brain will double in size in their first year, and most of that growth will happen while they’re asleep.
Your baby’s brain
Your baby’s brain actually started developing while they were about the size of a small seed in your womb – possibly before you even realized you were pregnant!
You know when people say a baby or child is “like a sponge?” It’s true! By the time your baby is born have all the brain cells they will need for the for the rest of their life, and those brain cells are ready and eager to learn.
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As your baby has new experiences, synapses and connections are formed, which means your baby is constantly learning. Their brain is storing these new learnings to be used for the rest of their life. This is how your baby will learn her name, what things are, who you are, etc. By 3 years old, your baby will have formed over twice as many synapses as the average adult.
WHAT'S A SYNAPSE?In our brains, information flows from one neuron to the next across a synapse. They are essentially the pathway information travels to get from one part of your brain to the next (so yeah, they’re pretty important). |
This early brain development is essentially the building blocks for your baby’s future learning, health, and behavior. The connections formed as an infant serve as an infrastructure for forming more complex connections when they’re older.
While it looks like your baby is just catching z’s, the reality is that an enormous amount of physical and mental development happens during their sleep. An essential layer of fat called myelin forms around nerve fibers during sleep, and recent research shows connections between the left and right hemispheres of children’s brains are strengthened during sleep. - Enfamil
Your baby’s brain also has the incredible ability to change and grow – literally. In their first three years, your baby’s brain can actually create more grey matter by altering synapses. Babies and small children who suffer from brain injuries can recover much more completely than an adult who has the same injury.
Crazy, right?
Sleep & your baby’s brain
After a long day, you need time to re-charge. It’s like that for your baby too – but with all that important stuff going on in their tiny sweet-smelling head, they need to re-charge more frequently than adults.
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The sleep-eat cycle that most newborns quickly fall into is really more like a recharge-refuel cycle for their growing bodies and brains. Sleep allows your baby’s brain to absorb what it’s learned throughout the day and store it properly.
Why sleep is important
We’re taught from an early age that sleep is important. Our parents and teachers try to tell us when we’re young. Your doctor harps on it at your yearly visit. And we rarely listen – because who’s got time for 8 hours of sleep every night?
FROM THE EXPERTS“Sleep is important for brain health in general. If you don’t get enough sleep, you can see negative effects on attention and emotional regulation.” - Alice Ann Hollland, Ph.D., ABPP |
But for your newborn, getting enough sleep is essential – and enough means wayyyy more than the 8 hours you should be getting every day. Babies need more like 14 to 18 hours, depending on their age.
Here’s why:
- Most of baby’s brain development happens during sleep: literally. This is when the connections between the left and right hemispheres of their brains are being formed.
- Brain synapses are formed during sleep: more than 1,000,000 million neural connections are formed per second during their first 3 years.
- Memories are formed and stored: your baby’s brain stores what they’ve learned that day during sleep
- Lack of sleep can cause bigger problems down the road: cognitive issues, developmental delays, etc. can sometimes be linked to not getting enough sleep
Other benefits of sleep
Besides the impact sleep has on your baby’s growing brain, it also impacts your baby’s mood, eating, behavior, etc., which is why an overtired baby quickly turns into a fussy baby.
A baby who gets enough sleep is going to generally be more agreeable, eat better (which is important for development!), less fussy, easier to soothe, more responsive, etc. A well-rested baby is a happy baby!
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Impacts later on
A 2008 study found that children sleeping less than 10 hours a night before age 3 were more likely to have language and reading problems, and even ADHD. A 2013 study showed that children with irregular bedtimes up to the age of three had more difficulty in reading, math, and spatial awareness than children with more consistent bedtimes. And knowing how sleep effects important early brain development, it makes sense that a lack of sleep can lead to negative emotional and behavioral effects as a child grows.
How can I make sure my baby gets enough sleep?
If you’re worried your baby isn’t sleeping enough, don’t panic – they’re not in for a lifetime of developmental issues just because they’ve fought off a few naps or refuse bedtime.
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It will take some time to figure out how your baby’s sleep cycle works. You can, however, start to instill some good sleep habits that will help them get enough rest from day one. Even though there might not be a set pattern or routine to your baby’s sleep immediately, you’ll probably notice the eat-sleep-play cycle. Try logging these activities to inform activity throughout the day.
You can also start with a pre-sleep routine. Once your baby’s sleep becomes less erratic and they have a more consistent bed time, this can become your bedtime routine.
Try swaddling to help keep your baby from getting overwhelmed or overstimulated, which can keep them awake. Swaddling recreates the womb environment to help calm your newborn.
FROM THE EXPERTS“When done correctly, swaddling can be an effective technique to calm infants and promote sleep.” - American Academy of Pediatrics |
And so you can get some sleep too (which is just as important), the Zen Swaddle is lightly weighted to mimic your gentle touch between cuddles, and help soothe your baby to sleep.
For more tips on how to help your baby sleep, check out these other articles from the Zen Blog:
Baby sleep simplified: newborn sleep schedules & patterns
How to get baby to nap: nap schedules through the first year
References:
Sleep and the Developing Brain – Ronald E. Dahl, MD
Sleep and Childhood Brain Development: The Critical Link – Robert Rosenberg, DO
Children and Sleep – National Sleep Foundation
Your child’s sleep affects their brain – Children’s Health
Baby Sleep-Time Mean Active Brain Development – Enfamil
The relationship between sleep & brain development in infants and young children - Snuza
Centers for Disease Control and Prevention: Early Brain Development and Health