The Science of Sleep

Structure of Sleep

Let’s talk about the structure of sleep. 

There are two main parts of sleeping : REM sleep and non-REM sleep.

REM is short for (Rapid Eye Movement)

The first part of the cycle is non-REM sleep. This sleep is split into 4 stages:

• Stage 1 is the time between being awake and sleep

• Stage 2 is the light sleep stage, where the heart and breathing rate regulate and the body temperature drops

• Stages 3 and 4 are deep sleep

Non-REM sleep is now believed to be the most important stage for learning and memory.

Following the stages of Non-REM sleep, your body then cycles into REM sleep. This is where your eyes move rapidly behind your eyelids and brain waves are more similar to what they are when you are awake. Breathing Rate increases and  the body becomes temporarily paralyzed as you dream.

The cycle then repeats itself four or five times throughout the night, and in each cycle the REM stage becomes longer than the previous.

Sleep Regulators

There are 2 main regulators for sleep: circadian rhythm and sleep drive.

Sleep drive is basically your craving for sleep. It is actually very much like cravings for food or water. Desire for sleep builds throughout the day like hunger, but unlike hunger however, your body can force you to sleep. If you have, let’s say, been staying up for 2 days in a row studying for your exams, your body can theoretically put you to sleep, even if you were, say in the exam itself or in an interview or whatnot. Your body can also do something called microsleep. These are episodes of sleep that last less than 30 seconds. For the brain to register that you are sleeping, it needs to last at least a minute, and so, often you see your body jerking up as it falls asleep for a bit. Other signs are excessive yawning, blinking and tearing up, or not realizing something happened, and so on.

Why Sleep is Needed

Finally, let’s talk about why we need sleep. I already mentioned that it rejuvenates the body,  but it also helps our brains for simple tasks. 

Sleep helps in something called brain plasticity, or the brain’s ability to take inputs or process information. Without sleep, not only would you have trouble understanding or processing information, but lack of sleep also harms your ability to remember information you take in. Sleep also promotes the ability to remove waste cells in your brain. Finally, lack of sleep can be a cause or accelerator of health problems in the body like migraines, seizures, high blood pressure and diabetes, and a lack of sleep harms your overall immune system and can lead to an increased chance of illness and disease entering and causing you harm. 

Conclusion

So, that is it guys. Now you know more about sleep, something we should all be doing and sacrificing, no matter the circumstance. I hope you found this as exciting and informative as I did, and if you want more info I have listed some sources at the bottom of this page. Thank you for reading!