While we sleep the brain works. To sleep well and feel refreshed in the morning we have to pass a full sleep cycle which repeats every 90 minutes and is the architecture of our sleep. When are sleep cycles taking place, what are the sleep stages and how do each influence our sleep?
Two main sleep stages:
- REM
A quarter of the night is at the first stage, REM (rapid eye movement), during which our eyes move rapidly. It happens because REM sleep is associated with dreams. Although we experience dreams during both stages, emotional dreams tend to happen at REM stage which we get to 90 minutes after falling asleep. During REM, sleep waves are faster and provide energy to the brain and body.
- NREM
The second stage. NREM, covers the other 75% of the night. “Is non-REM sleep important that much as it lasts so long?” – you may think. Actually, it is.
During NREM lots of crucial processes happen in our brain, while our eyes are static and sleep waves slow down. It starts after we close our eyes and divides into 3 more stages:
- Light sleep between being awake and falling asleep.
- We disconnect from our surroundings, heart-rate and breathing are regular, body temperature drops.
- Approaching deep sleep. Breathing, heart rate, blood pressure fall, muscles relax. Non-REM sleep helps restore tissues and promote muscle development as growth hormone is released.
If you want to know how to increase non-REM sleep length, track how long it lasts. In this case, sleep trackers like Goodsomni Lab are useful. Once downloaded they will bring maximum use.
What happens when you sleep
When everything is clear with the sleep cycle and sleep stages it’s time to get to know what’s happening when we shut our eyes.
- Memories creation
Thanks to sleep we remember things. All the information we gather in the day needs to be stored and sleep is the time when it happes. Different sleep stages take part in this process. During REM, the thalamus part of the brain is active and sends images, sounds to the cortex to make our dreams. Sleep cycle lasts and then NREM sleep takes over when short-term memories transfer into long-term ones and we learn to connect the dots, like associate pairs of words. Having sleeping disorders seriously impair the skill to keep your mind clear.
- Hormones making
While we sleep, our body makes hormones and lowers others. Melatonin (a hormone that makes us sleepy) and growth hormone go up, while cortisol, a stress hormone, goes down. That’s why the best pill for depression is sleep and it works visa versa. When sleep-deprived it can lead to stress. If you wondered, can sleep affect heart rate and does sleep repair cells, yes they do. Hormones releasing and the repairing of damaged DNA happens together. Sleep helps us to calm down and feel harmony.
- Sympathetic nervous system relax
All of us have had the feeling to fall into the bed with a thought “Finally! This is what I dreamed about the whole day”. Sleep repairs body and it’s a time of higher relaxation. It happens for a reason. The sympathetic nervous system responsible for the “fight-or-flight” response chills out. Muscle relaxation and deactivation are essential as without them, we’d wake up or walk around while having dreams in REM. So, the brain sends signals to the body to relax muscles, limbs, cool body temperature and slow the heart rate.
Sleep apnea, insomnia usually become the reasons for anxiety increasing and leads to depression. It’ll be wise to search for the problems in your sleep habits, such as lack of relaxation, inability to make new memories.
