What Happens In Our Bodies When We Sleep?

What Happens In Our Bodies When We Sleep?
Does our body “switch off” when we sleep? Mami Kempe / The Conversation, CC BY-ND 

Most of us might think sleep is like a light switch. That is, we go to bed, shut our eyes, and our body “switches off”. Then, when we open our eyes and wake up in the morning, we are “switching on” for the day.

But that is not true. There are changes that happen in our body during the night when we sleep.

The most interesting part of our body that changes during sleep is our brain. We know this because people have been measuring how active our brain is during sleep since the 1950s. They have done this by gluing small circular pieces of metal attached to wires (known as electrodes) to our head and near our eyes. These electrodes have shown that when we sleep, our bodies do not “switch off”. In fact, there are many things that our brain and eyes are doing.

Electrodes measure the waves produced by our brains. When we are awake, there are lots of these waves, but they are really small. So lots of tiny waves mean there is a lot of activity in our brains. Also, when we are awake, our eyes are moving around and looking at things - left and right, up and down, and all over the place.

When we shut our eyes to fall asleep, we begin to relax and fall into a very light sleep, which has been called “stage one” sleep. Our eyes begin to move left and right, back and forth, very slowly, many times, and very smoothly. It’s called “slow rolling eye movements” - and it’s something we cannot do when we are awake. During stage one sleep, our brains start to produce slightly bigger waves, and fewer of them.

Next is “stage two sleep”, which is a slightly deeper sleep than stage one sleep. There’s not much that is special about what our eyes are doing, but there’s a special wave that our brain makes called a “sleep spindle”. It’s a bit like the brainwaves seen in stage one sleep, but short, sharp and shiny.

The next stages of sleep are deep ones, and they are called stage three and four sleep. These stages are really deep, and really hard to wake up from. The brainwaves become really big - like those ones you might have seen at the beach.

 Get The Latest From InnerSelf

Finally, one of the most interesting stages of sleep is called “REM sleep”. REM stands for Rapid Eye Movement - so it means our eyes are moving all over the place during sleep - like when we’re awake. And our brainwaves are very similar to when we’re awake. But it’s during REM sleep that we dream.

Our brains move through the different stages of sleep - from one, two, three, four and then back to REM sleep. We go up and down through these stages all night, until we wake in the morning.

About the Author

Michael Gradisar, Professor in Clinical Child Psychology, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Recommended Books: Health

Fresh Fruit CleanseFresh Fruit Cleanse: Detox, Lose Weight and Restore Your Health with Nature's Most Delicious Foods [Paperback] by Leanne Hall.
Lose weight and feel vibrantly healthy while clearing your body of toxins. Fresh Fruit Cleanse offers everything you need for an easy and powerful detox, including day-by-day programs, mouth-watering recipes, and advice for transitioning off the cleanse.
Click here for more info and/or to order this book on Amazon.

Thrive FoodsThrive Foods: 200 Plant-Based Recipes for Peak Health [Paperback] by Brendan Brazier.
Building upon the stress-reducing, health-boosting nutritional philosophy introduced in his acclaimed vegan nutrition guide Thrive, professional Ironman triathlete Brendan Brazier now turns his attention to your dinner plate (breakfast bowl and lunch tray too).
Click here for more info and/or to order this book on Amazon.

Death by Medicine by Gary NullDeath by Medicine by Gary Null, Martin Feldman, Debora Rasio and Carolyn Dean
The medical environment has become a labyrinth of interlocking corporate, hospital, and governmental boards of directors, infiltrated by the drug companies. The most toxic substances are often approved first, while milder and more natural alternatives are ignored for financial reasons. It's death by medicine.
Click here for more info and/or to order this book on Amazon.


follow InnerSelf on


 Get The Latest By Email



The Day Of Reckoning Has Come For The GOP
by Robert Jennings, InnerSelf.com
The Republican party is no longer a pro-America political party. It is an illegitimate pseudo-political party full of radicals and reactionaries whose stated goal is to disrupt, destabilize, and…
Why Donald Trump Could Be History's Biggest Loser
by Robert Jennings, InnerSelf.com
Updated July 2, 20020 - This whole coronavirus pandemic is costing a fortune, maybe 2 or 3 or 4 fortunes, all of unknown size. Oh yeah, and, hundreds of thousands, maybe a million, of people will die…
Blue-Eyes vs Brown Eyes: How Racism is Taught
by Marie T. Russell, InnerSelf
In this 1992 Oprah Show episode, award-winning anti-racism activist and educator Jane Elliott taught the audience a tough lesson about racism by demonstrating just how easy it is to learn prejudice.
A Change Is Gonna Come...
by Marie T. Russell, InnerSelf
(May 30, 2020) As I watch the news on the events in Philadephia and other cities in the country, my heart aches for what is transpiring. I know that this is part of the greater change that is taking…
A Song Can Uplift the Heart and Soul
by Marie T. Russell, InnerSelf
I have several ways that I use to clear the darkness from my mind when I find it has crept in. One is gardening, or spending time in nature. The other is silence. Another way is reading. And one that…