HOW WE SLEEP – THE SLEEP CYCLE

Let’s look at how sleep occurs during the night. It is regulated by an internal body clock. Sleep goes in cycles throughout the night, moving back and forth between deep, restorative sleep, more alert stages and dreaming. Each cycle lasts approximately 90 minutes, with the deepest sleep occurring in the first or second phase. As sleep progresses, deep sleep periods become shorter, and more time is spent in dream (or lighter) sleep.

There are two main types of sleep:

  • REM (Rapid Eye Movement) sleep is when we dream most actively. During REM, our eyes move back and forth, as we are ‘dreaming in pictures’.
  • Non-REM (NREM) sleep consists of four stages of deeper and deeper sleep. Each sleep stage is important for the ...

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