How Does Sleep Cycle Work?

So that we can understand what the sleep cycle is and how it works, let’s take a look at its two most important components: 1. Slow wave sleep (also known as deep sleep) 2. Rapid eye movement (or REM) sleep During slow-wave sleep the body relaxes, breathing becomes more regular, blood pressure falls, and the brain becomes less responsive to external stimuli, which makes it more difficult to wake up. This phase is critical for the renewal and repair of the body. On the other hand, REM sleep is to the mind as what slow wave sleep is to the body. The brain is relatively dormant during most sleep phases. However, during REM, your brain becomes active. REM sleep is when your brain produces dreams and re-organizes information. It is in this phase that your brain clears out irrelevant information and boosts your memory by connecting the experiences of the last 24 hours to your previous experiences. This brain activity facilitates cognition and neural growth.

Differential Benefits

Slow wave sleep helps you recover physically while REM sleep helps you recover mentally. The amount of time you spend in these phases tends to decrease with age, which means the quality of your sleep and your body’s ability to recover also decrease with age.

The Circadian Rhythm

Circadian Pacemaker (c/o Wikimedia Commons)
The word circadian was coined from two Latin words: circa (around in English) and dia (day in English). Thus, circadian rhythm refers to the physiological cycle of different processes that happen over a time span of about 24 hours. These processes dictate your sleep cycle and can be greatly affected by 3 factors: • Light Light has probably the most significant effect. Staring into a light for 30 minutes or so can practically reset your circadian rhythm regardless of what time of day it is. More commonly, the rising of the sun and light striking your eyes trigger the transition to a new cycle. • Time The time of day, your daily schedule, and the order in which you perform tasks can all impact your sleep-wake cycle. • Melatonin Melatonin is the hormone that causes sleepiness and controls body temperature. This hormone is produced in a predictable yet regular cycle, increasing after dark and decreasing before dawn. Researchers believe that the regularity of melatonin production helps keep the sleep-wake cycle on track.

Final Note

So, what should you do to get a refreshing night’s sleep in order for you to wake up refreshed and ready to tackle the day ahead? Keep in mind the information above. All of this will help you recognise the importance of the various factors affecting your sleep cycle. You may also wish to check out our article about the 8 Easy Tips to Improve Your Sleep Quality.  


Extracted from an article by James Clear