What sleep does to your brain

sleep science

health

You might think that during sleep your brain shuts down, but you'll be surprised at how active it is!

Toby Richards

Sleep is essential for the health of your mind as well as your body; getting a good night's sleep has never been more important. Sleep helps to:

Regulate your appetite

Studies have shown that lack of sleep prompts your brain to release more ghrelin, the hormone that causes you to feel hungry. At the same time, too little sleep causes your brain to pump out less leptin, the hormone that makes you feel full.

What is Ghrelin?

Ghrelin is a hormone that is created and delivered mainly by the stomach with modest quantities additionally delivered by the small digestive system, pancreas and brain.

Ghrelin has various capacities. It is named the 'hunger hormone' since it promotes appetite, fat stockpiling, and food intake. If manually administered Ghrelin increases food consumption by up to 30%; it travels in the circulation system and acts at the hypothalamus, a zone of the brain vital in the control of hunger. Ghrelin has likewise been shown to act on areas associated with reward processing, for example, the amygdala.

Ghrelin likewise stimulates the release of growth hormone from the pituitary glans, which, in contrast to ghrelin itself, separates fat tissue and causes the development of muscle.

Ghrelin also affects the cardiovascular framework and plays a role in the control of insulin release.

Process and store memories

As you sleep, your brain works to solidify memories that you formed throughout the day. It also links these new memories to older ones, helping you make connections between different pieces of information to come up with new ideas.

In fact the most popular theory of memory creation says that without sleep we would not be able to create new memories at all! In the standard two-stage memory system we create the initial memories when we experience the event, but these are only lightly impressed in our minds, in temporary storage. Without building these memories into a more structured format in our brains they will be written over, and lost for good!

When we sleep these memories get replayed and stored away, our brains have the time to label and format the memories, being careful not to merge them with others, or overwrite ones that are there already. It's pretty amazing and sleep is the key.

Think more clearly and creatively

REM sleep, the part of the sleep cycle that involves dreaming, is key to boosting creativity. Sleep is an opportunity for the neurons that you’ve been using all day to take a break and repair themselves before you start calling on them again tomorrow.

Unlike the Slow wave deep sleep needed to form memoires, the first non-REM stage of sleep is a chaotic chorus of firing neurons, bathed in a chemical called acetylcholine that floods the brain in this stage. This randomness allows your brain to create links where you've not considered before, leading to unique insight and problem solving.

Einstein, Aristotle and Salvidor Dali have all tapped into the magic of non-REM sleep to fuel their creativity, the most famous being the key dropping of Salvidor Dali. By holding a key loosely between his fingers above a plate he created a sleep powered alarm clock, as he dozed off the key would drop onto the plate and awaken him, the short span of sleep being enough to discover some new creativity, as he put it:

The moment the key drops from your fingers, you may be sure that the noise of its fall on the upside-down plate will awaken you, and you may be equally sure that this fugitive moment when you had barely lost consciousness and during which you cannot be assured of having really slept is totally sufficient, inasmuch as not a second more is needed for your physical and psychic being to be revivified by just the necessary amount of repose.

Clear out harmful toxins

There's evidence the brain clears out toxic waste accumulated during the day at night, through convective motion of the fluid that bathes the brain, effectively giving your brain a deep clean.

The exact workings of this deep clean are still not exactly known, but from what scientists already understand about the stages of sleep we can postulate that the same movement of fluid that enables the creation of memories acts to wash away the accumulated toxins in your brain.

Without sleep we know that people suffer from a range of issues, there is a clear connection between a lack of sleep and psychiatric and neurodegenerative conditions. The cerebrospinal fluid that bathes your brain only reaches the levels high enough to clear the toxins during sleep, so without it you're in trouble!

Keep you looking good

During sleep growth hormone is realeased to do things like heal wounds or build stronger muscle tissue after a tough workout. But growth hormone is also used to fight stress and damage caused by the sun and pollutants that we’re exposed to daily. Having adequate sleep can help stave off premature aging by promting the growth of new, healthy cells that keep your skin looking younger, smoother, and more radiant.

Read More