The Five Stages of Sleep

And did you know that you experience all 5 stages, (over and over again), each and every night?

I must admit that I didn't, and I guess most of us don't usually give too much thought to sleep - until we can't get any that is!

If you're used to simply climbing into bed, turning off the light, and going straight to sleep, you probably don't realize how active your brain is while you're in the Land of Nod.

On the other hand, if you're someone who tosses and turns all night, spends hours staring at the ceiling, or sneaking looks at the clock, you may have an inkling that your brain isn't 'switched off' at night.

If you'd like to know just how busy your brain is while you snooze, check out my Benefits of Sleep page, I think you'll be surprised what you learn.

What are the five stages of sleep?

Four of them consist of non-REM (rapid eye movement/dream) sleep, and one is REM sleep - this is when you are dreaming.

You actually 'cyle through' all 5 stages of sleep several times (on average 4 - 6 times) each night, not always in the same order.

Here is a more detailed look at the the five stages of sleep -

• Stage 1
  This is a the lightest stage of sleep, the transition phase, where you feel yourself 'drifting off'. If you were to forget about the alarm clock and allow yourself to wake up naturally, Stage 1 sleep would be the last stage before you would fully 'wake up'.

  You don't spend too much time in Stage 1 sleep, maybe 5- 10 minutes or so, just enough to allow your body to slow down and your muscles to relax. However, it's interesting to know that research has shown that people suffering from insomnia, may stay in Stage 1 sleep for considerably longer.



• Stage 2
  This stage of sleep is still considered light sleep, but now your brain activity starts to slow down some, and your heartrate and breathing become slower and more regular. Your body temperature falls a little and you're beginning to reach a state of total relaxation in preparation for the deeper sleep to come.


• Stage 3
  This is the start of deep sleep (also known as slow wave sleep). Stages 3 & 4 are very similar, with no visible eye or muscle movement. If you were to get woken up suddenly during stage 3 or 4, you would be 'groggy' and confused, and find it difficult to focus at first. During stage 3, your brain waves are slow 'delta waves', although there may still be short bursts of faster waves of brain activity (also known as beta-waves) .


• Stage 4
  Of the five stages of sleep, this is the one when you experience your deepest sleep of the night. Your brain only shows delta-wave (slow wave) activity, and it's pretty difficult to wake someone up when they're in this stage.

  It's during Stage 4 sleep that children are most likely to suffer from bedwetting or sleep terrors. Stages 3 and 4 can last anywhere from 5 - 15 minutes each, but the first deep sleep of the night is more likely to be an hour or so. This is the time when the body does most of its' repair work, and regeneration.

  As we get older, we tend to spend less time in deep-sleep stages, perhaps there is a correlation here?



• Stage 5
  This is the stage when we find ourselves dreaming. Of the five stages of sleep, it's the only REM stage (sometimes also called 'active sleep'), and gets its' name from the rapid eye movements that characterize this period. Your blood flow, breathing and brain activity increases, and an EEG would show that during REM sleep, your brain is about as active as it is when you're awake!

  Another aspect of REM sleep, is that the muscles in your arms and legs will go through periods of paralysis. Scientists speculate that this may be natures' way of protecting us from acting out our dreams. The first period of REM sleep of the night usually begins around 90 minutes after you start drifting off, and lasts for about 10 minutes. As the night passes, the periods of REM sleep become longer, with the final episode lasting an hour or so.

  Babies may spend as much as 50% of the time they're asleep in the REM phase, for a healthy adult it is usually around 20 - 25%, and this then decreases with age.

Two of the most recent findings include the possibility of a link between REM sleep and depression, and an investigation about the effect REM sleep has on our ability to learn new tasks or retain new information.

Remember how your mom always advised you to 'get a good nights' sleep' to help you remember your school work, or fully learn how to complete some new task? Well, it seems that advice may have a scientific basis - proving moms really DO know best!

Page/Article Links: