Baby Sleep-Time Means Active Brain Developmentp

3 ways sleep helps your baby’s brain development—plus, simple steps to encourage healthy sleep.

Bedtime and naptime are highly productive periods for your baby. Here’s a peek inside how sleep powers mental and physical development—and what you can do to encourage it.

Ah, the sweet sound of a sleeping baby. You may feel relief when your baby falls asleep because it means you can finally rest too. But here’s another reason to feel good about those baby z’s: Sleeping is an important way your baby grows smarter.

From birth to age 2, children spend more time asleep than awake. In all, 40 percent of childhood is spent in slumber. But it only looks like your baby is doing nothing. In reality, an enormous amount of both physical and mental development takes place during sleep.

Why the Growing Brain Needs Sleeps

Your child cycles through two main kinds of sleep: active (rapid eye movement, or REM) and quiet (non-REM). In active sleep, the brain is busy; this is when we dream. In non-active sleep, the blood supply to the muscles increases, energy is restored, and tissue growth and repair take place.

In the womb, a baby spends about 80 percent of the time in active sleep, and until about 6 months of age, about half of sleep is in the active phase. Not coincidentally, it’s during these early phases of life that the brain is growing most busily.

Simply put, sleep builds your child’s brain.

  • Especially during active sleep, key neuronal (brain cell) connections are made—the brain literally lays down the tracks for everything it learns, and it also prunes away little-used connections.
  • An essential layer of fat called myelin forms around nerve fibers during sleep.
  • Connections between the left and right hemispheres of the brain are also strengthened in children during sleep, recent research shows.

These developments help brain functions mature, influencing critical abilities such as language, attention, and impulse control. In fact, this beehive of brain activity during sleep has a direct effect on a child’s ability to learn and grow. It may even potentially affect developmental and mood disorders.

How You Can Support Your Baby’s Sleep

Some simple steps can help your baby get the sleep she needs for strong brain development.

Recognize the importance. Sleep is as crucial to supporting your baby’s brain as proper nutrition (such as a diet that includes fats like DHA), the stimulation of your voice, and having interesting things to look at. A Canadian study of toddlers found that those who got the most sleep had the best executive functioning—including the ability to pay attention, set goals, and stay on task.

Learn to identify signs of sleepiness in your baby. They can vary by age and personality. Some little ones are eye-rubbers; others get fussy.

Try to put your baby to bed when she’s drowsy, rather than sound asleep. Over time this strategy may help her learn how to get back to sleep on her own when she inevitably awakens. (All babies awaken briefly between sleep cycles, about every one and a half to two hours.) If you always rock your baby to sleep, she may expect this when she wakes up in the night.

Consider swaddling for sounder sleep. Some research shows that babies younger than 6 months sleep better when snugly wrapped in a blanket. But other experts are concerned that tight swaddling could interfere with the development of the hip. If you want to try swaddling, talk with your doctor about how to do it properly so that the blanket is not too loose, covering the head, or too tight and interfering with breathing.

Take full advantage of alert, awake time. It’s important to provide interesting things for your baby to see and do by day. This includes giving her some colorful toys, having “conversations” with her, and bringing her outside. The busier your baby’s waking hours, the more likely she’ll sleep well at night.