What happens when you sleep?

What happens when you sleep?

Sleep is an important part of your daily routine and you spend about a third of your time doing it. So what is actually going on during that time? 

Silentnight’s sleep expert, Dr Nerina Ramlakhan, explains: “When we sleep, most of our sensory input stops or slows down, as do many of our physiological processes.”

So, what does our brain actually do? Dr Nerina Ramlakhan suggests: “We are unaware of ordinary sounds and close our eyes to eliminate our visual response. Our nervous system slows down our breathing, heartbeat and blood pressure. Waste creation also decreases to prevent disturbances during our sleep, while our physiological functions are minimised, our brain adjusts itself to a reduced sensory input and operates on a very basic level.”

Whilst we are asleep, the levels of stress hormones that are produced during the day drop off – adrenaline, noradrenaline and cortisol levels subside. This stress balancing the effect of sleep is very important.

Dr Nerina mentions: “During a deep sleep, we get the kind of sleep that really refreshes and rejuvenates the body – the kind of sleep that we all want. Levels of adrenaline, cortisol and other stress hormones start to drop and the brain starts to produce the hormones needed to repair the body. This is the sleep that keeps our immune system robust and our skin looking fresh.”

Sleep is so important to many of the functions of the brain, including how nerve cells communicate with each other. Your brain and body even stay remarkably active while you sleep. Research suggests that sleep plays a housekeeping role that removes toxins in your brain that builds up while you are awake. 

Sleep affects almost every type of tissue and system in the body – from the brain, heart, and lungs to metabolism, immune function, mood, and disease resistance. 

Each 90-minute stage of sleep is made up of four phases of non-REM; When you’re first drifting off into REM sleep and after your REM sleep period is over and you are waking up and REM sleep; Better described as a 90 minute period during the night of deep sleep. The non-Rem portion of sleep is 1 to 4. 1 and 2 are light sleep and are often described as the ‘warm-up for good deep sleep. 3 and 4 are a slow wave or deep sleep, this is where our brain activity slows down.

Silentnight’s sleep expert, Dr Nerina Ramlakhan, explains: “We sleep in 90-minute cycles and each cycle consists of light sleep, rapid eye movement sleep, and deep sleep. Pure or ‘clean’ sleep is about having the right amount of these three components.”

The stages of sleep are important, it lets your mind slow down and shut off for a few hours. If you have trouble sleeping check out our blog You Are How You Sleep, where you can find out the habits for a great nights sleep.

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