“The typical dreamer, after waking, has no more idea where he spent the night than an amnesiac drunk.” – Robert Moss
Simply put, there are 2 phases of sleep: quiet and active. There are 5 stages to the sleep cycle. Stages 1 – 4 are quiet, and stage 5 is active.
Let’s walk through the 5 stages of the sleep cycle as they occur.
Stage 1 is the part of your sleep cycle when you are getting drowsy. The eyes are closing, and your body is preparing for the Land of Nod. This stage usually lasts no more than about 10 minutes. It is a transition between sleeping and wakefulness. Your brain is experiencing theta waves, which are low frequency.
From here, you move on to stage 2, which is a light sleep. The brain waves produce bursts of rapid activity called “sleep spindles”. The body temperature decreases and the heart rate slows down. This stage lasts about 20 minutes.
Stage 3 is a transitional stage between stages 2 and 4, and the most significant change between them are the brain waves moving into deep, slow, delta waves.
Stage 4 is the deepest of sleeps, which lasts about 30 minutes. Here, sleepwalking, sleeptalking, and bedwetting can occur.
After you move through each of these stages, you repeat stages 2 and 3. Then we move on to stage 5, which is REM (Rapid Eye Movement). Here is where dreaming takes place, and where our playground of interest lies. This is the environment of the Oneironaut.
Stage 5 is a dream state, where the muscles in your body become paralyzed, but heart rate, brain activity, and breathing are very active. It takes about 90 minutes to reach this initial stage during the cycle, from the time you lie down until you reach REM sleep.
From here, you go back through the stages before repeating stage 5. As the night progresses, your REM stage lengthens while your delta, or stage 4 decreases. You will likely go through about 4 or 5 of these cycles in a given night.
For more information on the sleep stages, go here, here, or here.
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