What Happens When We Sleep?

A girl sleeping on bed while listening to songs

Studies say we spend a collective 25 years just sleeping. That’s two decades and a half spent entirely on resting our bodies! That established it’s a no-brainer that sleep is important for us to survive. But do you know what happens to us when we sleep?

In the early 90s, there was a belief that sprung around saying that sleep was merely a passive activity that left the brain and the body dormant. But modern scientific studies debunks that myth rather hastily. The truth is, sleep is an experience in which the brain encounters a series of activities. To maintain a regular sleep schedule is hard – one has to willfully find ways to sleep earlier than used to and wake up after eight hours of blissful sleep.

To be more specific, sleep can be broken down to two different stages: rapid eye movement (REM), and non-rapid eye movement (NREM). A huge chunk of our sleep is NREM, covering about 80% in collective hours of sleep. This sleep cycle is defined by sleep spindles and delta waves—both of which are considered electrical brain patterns. This is the period where we’re considered to be in deep sleep the most. As you move into the REM stage, your eyes move rapidly despite your lids being closed. During this time, brain waves closely resemble the brain activity during the state of consciousness. One’s breath rate progresses and the body temporarily becomes paralyzed as one is led into dreaming.  

woman sleeping on white bed holding pillow

So, What Happens When We Sleep?

Science tells us that sleep drive and circadian rhythms are the two main processes that temper sleep.

Circadian rhythms are governed by a “time clock” found in the brain. One elemental function of this clock is to respond to light cues, spiking up nightly melatonin hormones, then turning it off when it discerns light. That said, individuals with blindness may find it more difficult to sleep due to the inability to reposed and detect cues involving light.

Sleep drive also plays an irreplaceable role in the whole time in REM sleep equation. The way it hungers for food, your body craves sleep, just as much. All throughout your day, the need for sleep builds up, and so when it’s finally reached its peak, you’re bound to give in. The only difference is that, when you’re hungry, your body can’t feed itself. But when you’re sleepy, it doesn’t matter where you are, you’re body will demand it and it will manifest. When you’re physically drained, it’s also natural for you to experience episodes of microsleep. This is also why napping for a little over half an hour can decrease your sleep drive at night.

Why Sleep Is Important?

If you’ve ever felt sluggish after an insufficient night’s worth of sleep, it’s not surprising that your brain doesn’t respond as sharply as you’d like it to. It’s important to understand that brain plasticity to flourish, a substantial amount of sleep needs to be reached. The brain’s capacity to adapt to information can slow down if it hasn’t rested. If we don’t sleep enough, we become a lot slower at processing what we learn throughout the day. Not getting enough sleep also ruins our memory. Time and again, science has proven that sleep improves waste product elimination from the brain cells. This isn’t entirely possible when the brake is awake.

Furthermore, sleep is important for the rest of the body, as well. Should we not sleep well enough, our health risks expand. Symptoms of increased heart rates, seizures, depression, migraines, and even high blood pressure may become worse. One’s immune system is also put in danger, exposing one to the great likelihood of acquiring an illness.  If you didn’t know, sleep contributes a lot to metabolism, too. So much so, that missing even just one night can already increase one’s chances of diabetes.

All these pointed out, there are many fantastic things that a person can enjoy if he or she wilfully chooses to rest.

Here Are Amazing Things That Happen to Your Body Once You’re Well-Rested

Your nervous system learns to relax

When you sleep, your sympathetic nervous system is given the opportunity to relax. Take note that it’s your nervous system that largely contributes to whether or not you “fight or flight” when certain moments call for it.

A woman doing the yoga

Research says that when we stop ourselves from enjoying good sleep, an increase in sympathetic nervous system activity is observed. Consequently, an increase in blood pressure can be noticed, too.

An abundance of hormones

A variety of different hormones is released during sleep, each one with a distinct purpose. Our body is such a complex being that it is truly incredible to know what happens when we sleep.

Melatonin, for example, manages your sleep patterns. Levels vary in the evening, making you drowsy. When you fall asleep, the growth hormone, coming from the pituitary gland, is released, too. 

Your brain continues to sort the day’s information

As established earlier on in this article, your brain does not shut down when you sleep. Far from it, actually. When you slumber, your brain becomes busy sorting information and processing the data involved in the day. This procedure is incredibly important to sustain and retain long term memories. During this time, your brain notes all the information it needs, and prepares these memories for when you need to use them in the future.

Your ADH controls your peeing

Has it ever occurred to you that during the day the need to go to the toilet is necessary every once in a while, but at night when you sleep, you barely feel the necessity?

The anti-diuretic hormone, also known as the ADH, turns off the need to pee every so often at night.

Can’t sleep at night?

There are many reasons why a lot of us have difficulty sleeping at night, but one of the leading causes is mental stress and anxiety. Both problems are so strong, they dictate, rather unhealthily, what the brain thinks of and when it can rest. As a result, one stays up late feeling down and unsure of many things. Now that you know what happens when we sleep, you must take lack of sleep much more seriously.

Insomnia, too, is one of the plenty of sleep disorders the national sleep foundation rallies behind. It’s unclear why certain people, sans anxiety, have a difficult time sleeping after a loaded day’s worth of labor. Many scientists associate the reluctance of sleep with mental illness, but it’s never good to self-diagnose. Consult a sleep expert today! We hope you have enjoyed reading about what happens when we sleep and if so, we hope you take extra time to schedule your sleep and enjoy eight full hours of it.

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