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Showing posts with label sleep patterns. Show all posts

Circadian Rhythm Explained and How It Impacts Sleep

Circadian Rhythm Explained and How It Impacts Sleep. How light impacts sleep.
Circadian Rhythm Explained and How It Impacts Sleep. How light impacts sleep.

When it comes to helping our children and ourselves get healthy sleep, there are several factors to consider and be mindful of. One such factor you will see me talk about often is the circadian rhythm.

The circadian rhythm is a sleep regulatory system. The circadian rhythm is an internal body clock. This is something within your body that helps impact your sleep patterns. Healthy Sleep Habits, Happy Child describes it as being something that switches on and off genes in response to light (see page 15). It is a molecular clock that is set by sunlight. The purpose of it is to ensure the body sleeps when it should and is awake when it should (along with other body factors. For the purpose of this post, we will focus on the impact it has on sleep). This sleep system is impacted genetically, so it is different from person to person (just like eye color). While it is genetic, it can be impacted by light, temperature, melatonin, and chemical reactions.


What is a Sleep Transition (and How Does It Impact Naps)


When Brayden, my oldest child, was first born, I would rock him to sleep. He fought that rocking with as much effort as a mother bear would put into protecting her little cub. He cried and he thrashed, but I eventually got him to fall asleep. It took so much time and effort to get him to sleep that I would hold him for a long time before finally trying to lay him in his bed to sleep. I did not want him waking up without a real nap!

Pretty much as soon as I would put him in his bed, however, he would wake up! I could not understand why! We were both tired and exhausted.

Today, I know why. It was because I was holding him so long that I was putting him down right at his sleep transition. 

A sleep transition is when the body moves from one type of sleep to another. Did you know that the body has different types of sleep? You have probably heard of REM sleep. REM is a lighter sleep when we are dreaming. We also have deep sleep, or non-REM. The time the body slips between the two types of sleep is our sleep transition.

The sleep transition is the moment that we can all be woken up most easily. That means if you are moving your baby from your arms to the bed right at the transition, your baby is more likely to fully wake up instead of slipping into a deeper state of sleep. The same is true for a dog barking, sister yelling, or the doorbell ringing right at the sleep transition. This post contains affiliate links.

These sleep transitions happen about every 45 minutes (as explained in The Baby Whisperer Solves All Your Problems -aff- on page 172). That explains why much of the time, short naps are 45 minutes long. As soon as your baby falls asleep, you have approximately 45 minutes until the transition happens. If your baby passes that transition and stays asleep, then your baby will sleep another 45 minutes, at least. 

REM sleep and deep sleep do different things for your body. "...high amounts of REM sleep, under the influence of low melatonin levels, help direct the course of brain maturation early in life" (Healthy Sleep Habits, Happy Child -aff- pages 28-29). "...REM sleep is especially important for restoring us emotionally or psychologically, while deep, non-REM sleep appears to be more important for physical restoration" (Healthy Sleep Habits, Happy Child -aff- page 29).

That means our children need longer than a 45 minute nap to get both benefits of sleep.

TIME OUT! For any of you with a chronic short napper who is no freaking out more than you already were, please take heart. Brayden took 45 minute naps until he was 6 months old. Today he is a very smart (gifted) 11 year old. So don't think your child is doomed if he/she is taking short naps. So relax. Continually strive to get longer naps, as I did, but do not let short naps ruin your day.

Now you know that a transition happens at 45 minutes and what the body is doing when it transitions. Your baby will most likely shift at this transition point. Some babies even cry out (they will keep their eyes closed and appear fully asleep other than crying out). Some will wiggle around quite a bit. If left alone at this transition, and not woken up by some loud noise or other factor, your baby will go back to sleep.

The sleep transition is why a sound machine can be so helpful if you have older children and/or live in a noisy area. The sleep transition is also a big reason why swaddling is helpful in early months. When your little one is transitioning, rather than startling himself right into awakeness, he can squirm a bit and then go back to sleep. 

The sleep transition is why sleep props are a bad idea. If your baby relies on a certain prop to fall asleep and is unable to fall asleep on his/her own, when the transition comes, your baby will wake up rather than slip into the next sleep cycle. 

This is why if your baby is waking after 45 minutes, you need to figure out what is it that is causing your baby to come fully awake rather than slipping into the next sleep cycle. Is there hunger? Is there pain bringing your baby to full alertness? Is there some noise? Is your baby too hot or cold to comfortably sleep?

Understanding what a sleep transition is can help you help your baby get better sleep. I may not have realized what was going on when my oldest was a little one, but now you know! Here is to better sleep.

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Newborn Sleep Patterns

Despite the fact that we all sleep daily, sleep is not necessarily "intuitive" for us. There are many facets about sleep we don't understand in ourselves (What time is best for you to go to bed? What time to wake up? How many hours are best for you? Do you sleep better with or without socks? etc.). Figuring out the sleep of your new baby can be quite the project.

Newborn Sleep PatternsNewborns usually have a regular pattern to their sleep, and understanding that can help you in understanding what is going on and what you can do to help facilitate great sleep. This post contains affiliate links. 

1-Newborns Make Noise Often, But That Doesn't Mean They Are Awake
A brand newborn is usually super noisy when first born. They make all kinds of grunts, sighs, "huh's"... They couple these noises with eyes fluttering open and often smiles. It is adorable! It is fun to watch, but do not get baby up every time you hear these sounds. This is just a noisy part of the sleep cycle. Let baby continue to sleep unless it is time for baby to be eating anyway. 

2-Sleep Cycles Change Every 45 Minutes
A newborn goes into sleep in REM sleep (See Healthy Sleep Habits, Happy Child page 59). About 45 minutes into a nap, the baby will transition into non-REM sleep. These transitions happen about every 45 minutes. At the 45 minute mark, your baby will stir. Your baby might make noise and might even open her eyes. Your baby might just shift slightly. Do not mistaken transitioning for waking up. Let your baby move into the next sleep state. 

3-Body Temperature Influences Sleep
Healthy Sleep Habits, Happy Child talks about biological rhythms starting on page 50. One influence on sleep is body temperature, and this remains true even up to adults. There isn't a way for you to really measure or respond to this, but know that as a baby gets to about 6 weeks, baby's temperatures start to get closer to what is best for longer night time sleep. There are biological factors out of your control that will impact how well baby sleeps at night. 

4-Melatonin Impacts Sleep
Melatonin is a hormone that comes from your pineal glad. Melatonin helps control your sleep and wake cycles. A newborn is born with "high levels of circulating melatonin" that came from the mother while in the womb. That is present for the first week. This is when you should sleep ;). 

After a week, all of that melatonin wears off and the baby is left with...not much. Around 6 weeks old, "melatonin begins to reappear as the baby's pineal gland matures" (page 51). The levels are "extremely low" until 12-16 weeks old. 

You can see from those numbers that they coincide with ages that babies start to sleep better. 6 weeks, followed by about 12...sound familiar? 

And do not decide to give your baby melatonin to induce more sleep. It has not been tested on babies. Also, I have to think there is a reason babies were designed the way they were designed by someone smarter than we are, so don't medicate or supplement your baby against what every healthy newborn baby naturally does--decrease melatonin levels. 

5-Newborns Do Not Stay Awake Long
Your newborn will be up for a very short time before needing to nap again. Your newborn will be awake anywhere from 30-60 minutes, including feeding time, before it is time to sleep once again (see my post Optimal Waketime Lengths to figure out how long your baby should be awake). Do not fight your baby on this. Let your baby sleep and your baby will sleep better overall. Overly tired babies start to sleep very poorly. 

If you want more time with your baby, you can absolutely hold your baby sometimes. It is wise to be aware of the amount of time since baby fell asleep. Do not try to put baby down in her own bed right around the 45 minute mark. This will likely wake her up since she is transitioning. Put her down before or after the transition if you are going to. If you hold your baby through the transition, do not try to wake the baby up during the transition. Let baby get into the next sleep cycle. 

I hope this information helps you understand the sleep of newborns a bit better.

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