The Stages of the Sleep Cycle

the sleep cycle

For as much as I love sleep, I would consider myself an expert on the subject. The reasoning behind this logic is that I am very good at sleeping. It is my favorite past time, one of the many things I am good at. If you were to ask me about the five stages of sleep, I would look at you like you’re speaking a foreign language. If you ask me what a sleep cycle entails or how many sleep cycles a person goes through a night, I would pretty much be Harry Potter standing next to Hermonie Granger in any of the Harry Potter books – clueless and dumbfounded. So am I really an expert on sleep? Not in the slightest, but I am ready to learn all about this thing that I so dearly love.

To give myself a tad bit of credit – I did know that there are different stages of sleep. As to what each stage is called and what goes on in said stage, I could not tell you. There are a total of five stages; stages one through four is considered non – REM sleep and the last is REM sleep.

Stage one is where you can be easily awakened – you are no where near deep sleep just yet. At this stage, your eyes move around slowly and your muscle activity slows. It is said that during this stage many people feel as if they are ‘falling.’ As you enter into stage two, you still have not reached deep sleep yet, but you are not going to be easy to wake. During stage two, your brainwaves slow, but there may be an occasional burst of rapid brainwaves, all eye moment ceases, and your body temperature falls as your hear rate slows. Both stage one and two are known as light sleep.

When you enter stage three, you are now in deep sleep mode. At this point in your sleep, delta waves (extremely slow brainwaves) are combined with smaller, faster brainwaves. During stage three is where most people tend to experience sleepwalking, terrors, talking during sleep, and/or bed-wetting. These behaviors take place while transitioning between non- REM and REM sleep. Stage four is exactly the same as the previous stage, but at a more concentrated level. During this phase is where you get the most rest throughout the night. This is when the body and the immune system restore themselves and prepares for the upcoming day.

sleep pattern.png
Stage five – REM sleep – is where you experience the most vivid dreams. Your brainwaves are similar to that of when you are awake, and, although your eyes are closed, they move from side – to – side. It is believed that REM sleep occurs about 90 minutes after falling asleep, and the first REM cycle lasts about 10 minutes. While we sleep, we go through multiple sleep cycles – I will touch on the next. REM sleep lasts longer and longer through each cycle. During this stage, your breathing will become shallow and irregular, and your muscles are paralyzed for a short amount of time. Your heart rate and blood pressure rise and the body lose the ability to regulate its temperature.

sleep cycle
While we are asleep, we go through each of these stages multiple times throughout the night. We go through what is known at a sleep cycle – the period of time it takes for someone to go through each of the stages mentioned above. It is important to note that the cycle does not revolve in numerological order, rather is starts from light sleep and progresses to deep sleep, back to light sleep, then moves on to REM sleep. Once REM sleep is achieved, you begin at light sleep once again. The first sleep cycle lasts for about 90 minutes, and every other cycle after that lasts anywhere from 100 – 120 minutes. It is believed that we go through at least four to five cycles each night.

Whew! That was a lot of information. Much more information about how your brain works while asleep than I expected, but still very good to know. Although scientists do not have a more extensive way to monitor our brainwaves while asleep, I think that what they have discovered is truly amazing.

For more information on the different stages of sleep, please visit:

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1 Comment

  1. Nikki says:

    Ok seriously that was soooo amusing because I too love sleep…then totally educational, keep it up that’s good stuff!!!!

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