Do you know how the sleep cycle works? It certainly isn’t as straightforward as going to sleep at night and waking up in the morning. Your body goes through multiple cycles every night that all vary in levels of brain activity. So here are the four stages of sleep that we go through…
As you’d probably suspect, the first stage of sleep is light, where your eye and muscle activity are slowly decreasing. You’re easy to wake up in this stage, and it’s here that you’re likely to experience twitching or the infamous hypnic jerk.
This is the period that prepares you for deep sleep, muscle activity decreases further and your heart rate and temperature drop further too. Brain waves slowly decrease, however, there will be small bursts of brain activity in this stage still.
In this stage, you’re in much deeper sleep, the brain emits delta waves which prepares you for the final stage. It would also be fairly difficult to wake up at this point, as this is the period of sleep that helps you feel refreshed in the morning. With restoration happening in this phase, it makes sense that this stage occurs for longer periods earlier in the night.
In the most intense stage of sleep, your eyes move from side to side quickly whilst your eyes are closed (of course). In this phase, you’re most likely to have dreams, which are caused by extreme brain activity in which the frequency isn’t so far off that of being awake. Also, an interesting fact about this stage of sleep is that our limbs become temporarily paralyzed, and that’s to stop us from acting out our dreams!
These four stages of sleeping form one full cycle of sleep, and only takes around 90 minutes. For a good night’s sleep, you’ll go through this cycle 4-5 times. Both NREM and REM are important for being able to attain memories, as well as feeling refreshed in the morning.
Isn’t it quite bizarre how we experience huge fluctuations in brain activity when we sleep? Did you know that this is how the sleep cycle worked before reading this? Let us know what you think in the comments below…