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What Are the Main Functions of Sleep?

Most people know how important sleep is for daily health, but that doesn’t mean its individual functions are as well-known. In fact, sleep, its functions, and benefits are constantly studied by neuroscientists, biochemists, and pathologists for new findings.

If you’ve asked yourself, “What are the main functions of sleep?” wanting to know more, it’s a great mindset to be in. This blog post covers all of the most important sleep functions so you can discover just how impactful every part of nightly rest is.

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Memory Formation and Retention

The creation and crystallization of memories is one of the biggest and most important functions of sleep. Leading brain plasticity scientists report that sleep is what allows the brain to form new neural connections, reorganize itself, and restructure essential functions.

Here are seven details about memory formation and retention as they relate to the main functions of sleep:

  • While your brain can begin memory formation during different stages of sleep, deep sleep is when your memories are solidified. That’s the stage of sleep when your mind and body are deciding what to keep and what to discard. REM sleep is when your mind connects related memories and consolidates your experiences.
  • Your memories are based on neural connections. Much of how your brain grows and learns is based on neural connections that are updated and refreshed each night during sleep. While scientists haven’t reached a consensus on how new neural connections establish memories, many believe that the behavior of specific brain waves is involved in this process.
  • There are different categories of memories. Researchers have found that your brain categorizes memories based on its associated brain function. Take a closer look at the types of memories here:
    • Sensory memory: Your brain takes information and experiences you’ve gathered about the physical world and puts them into this bucket. While sensory memory has unlimited capacity, it only lasts for about half a second to three seconds.
    • Working memory: This is where your brain puts information that you need from a time frame of a few seconds up to 10 to 15 seconds. Working memory helps you accomplish tasks efficiently without remembering unnecessary amounts of information.
    • Short-term memory: Your brain creates short-term memories for information that needs to be remembered for just a few seconds. This is often useful when playing games, having casual conversations, or checking temporary information.
    • Long-term memory: This is where most of your memories are created, updated, and retrieved from. Long-term memory is essential for executing ongoing work, remembering events and conversations, recalling your developmental years, and everything else you need to lead a functional life as a human being.

Memories are also connected to dream activity when sleeping. Sometimes your mind references parts of your memories in dreams, and dreams can also be stored as memories. In the next section we’ll look at some major functions of dreaming.

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Dreaming is another major function of sleep that scientists study and write about to this day. During sleep, the body goes through several phases including rapid eye movement (REM) and non-REM sleep. The brain is highly active during REM sleep and while dreams can occur during any phase of sleep, most people report their most vivid dreams during REM stages.

Dreams are thought to be the brain’s way of processing various skills practiced and information gathered during the daytime. Dreams also work to consolidate and store memories, process unconscious beliefs and struggles, and act as an emotional filter for events happening during waking life.

Getting the kind of sleep that’s conducive to positive dreams is important to maintain physical and mental health. Not getting enough sleep can eventually lead to poor concentration, memory loss, and even depression.

Similarly, not getting enough dream time can lead to difficulty processing information and emotions. Science shows that most people dream anywhere from four to six times per night, but don’t remember most (if any) of it. In fact, a Science journal article as recent as 2019 found that the mind’s memory development function is impaired during REM sleep.

The non-REM phases of sleep (deep sleep) are important for physical rest and restoration. Without enough deep sleep, your body can’t repair inflamed and wounded tissues, remove cellular waste, and give your brain the opportunity it needs to reset.

Most consumers’ understanding of what dreams do and don’t do is unfortunately clouded by cultural myths. We compiled several dream myths and facts so you can lay misconceptions to rest.

Most Common Myths About Dreams

Dreams are already fascinating and confusing experiences, so it’s little wonder there are a lot of misconceptions about them. Here are four of the biggest:

  • Dreams are completely meaningless. While it’s tempting to shrug dreams off as a weird collection of larger-than-life mental pictures, they’re normally tied to something in your life. Those dreams about being late for a test, appearing naked in public, or trying to swim but it feels like quicksand are often based on real fears.
  • You can only dream during REM sleep. A pop-culture-esque understanding of sleep research has given rise to the idea that dreams only happen in REM sleep, but this isn’t true. Scientists have repeatedly found that while REM sleep is most conducive to dreams, they can occur anywhere in the nightly sleep cycle.
  • Remembering all of your dreams is a sign of quality sleep. Somewhere along the way, people got the idea that remembering your dreams indicates good sleep, but this is false. Sleep research has found that people who have greater wakefulness throughout the night are more likely to remember dreams, showing a correlation between poor sleep and easy dream recall.
  • A nighttime dream can kill you. Believe it or not, people used to think that bad dreams could kill someone. This myth was propagated in the 1980s when southeast Asians were fleeing violent regimes and dying mysteriously in their sleep. Researchers later found that Brugada syndrome–a rare genetic disorder that can cause a dangerously high heart rate–was the culprit in some of these instances.

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Most Important Facts About Dreams

With common sleep myths addressed, we can look at dream facts that science backs up. Here are some of the coolest points about dreams:

  • About two thirds of dreams happen in black and white pictures. Scientists have found that most dreams occur in a visual format, specifically imagery. The latest research shows that only one third of dreams take place in color.
  • Part of your brain shuts down when dreaming. Modern research has shown that your dorsolateral prefrontal cortex, one of the foremost parts of your brain, is deactivated while dreaming. This part of your brain helps you make sense of complex information while awake, so this helps to explain why dreams often involve disparate, nonsensical information.
  • Many scientists still disagree about the meaning of dreams. Some say it’s the mind’s attempt to provide a form of self-therapy for real-world struggles; others say they’re collections of jumbled concepts or the brain clearing out its junk drawer. Still others believe the truth is somewhere in the middle, with the mind trying to add a structure to otherwise difficult-to-digest information.

Dreams certainly enrich the sleeping experience as long as they’re positive. Even if they’re negative, they can be valuable signposts as to what should be addressed in one’s waking life.

Sleep and weight loss also go hand-in-hand. Keep reading to find out how healthy sleep automatically keeps your weight in check and can even be part of a weight loss program.

Weight Regulation

Getting the right quantity and quality of sleep each night as part of a weight loss or management plan is a fast-growing area of interest in sleep science. By separating fact from fiction, you can employ what works for almost immediate results.

While preparing for sleep, your body begins producing less of specific hormones and more of other hormones. Leptin is the appetite-suppressing hormone which your body creates more of and ghrelin is the appetite-stimulating hormone that your body reduces production of for sleep.

Research also shows that sleeping with artificial light on can lead to weight gain. Scientists have found that the body’s inherent weight management systems associate daylight with weight gain due to age-old survival mechanisms in ancient humans.

If you don’t get enough sleep, you may wake up feeling hungry. This is often because your body didn’t produce enough leptin while sleeping, thereby not causing enough of a distinction between daytime and nighttime.

Getting enough rest every night and prioritizing deep sleep is one of the easiest and most fun ways to drop excess weight. Here are the most important points to know:

  • Getting enough sleep decreases appetite. When you go to sleep, your body slows the production of appetite-stimulating hormones and increases the production of appetite-suppressing hormones. The more in sync your sleep schedule is, the more likely you are to have a balanced appetite during the day.
  • Proper sleep promotes smarter food choices. A 2021 Food Quality and Preference study found that sleep deprivation causes your brain to get more excited by food. This indicates that it’s likely easier to make bad dietary decisions when you haven’t gotten adequate rest. By sticking with at least seven to eight hours of sleep per night, you keep your executive functioning in great shape, which means you’re more likely to choose healthier meals.
  • Going to bed at the right time prevents snacking. If you’ve ever tried going more than five to six hours without a regular meal, you know what it’s like to feel “hangry.” This is the informal term we use to describe being so hungry that you become irritable. The later you stay up on a given day, the more likely your body is to desire food. Committing to a regular bedtime prevents such late night snacking and concurrently provides motivation for regular meal times.
  • Robust sleep promotes a strong metabolism. Your resting metabolic rate (RMR) is the rate at which your body burns calories without exerting any effort. Scientists have found that less sleep leads to a lower metabolic rate, meaning it’s harder to lose weight when your sleep schedule is out of whack. Going to bed at the same time each day is essential to keep your RMR at a good level.

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Mental Function and Cognitive Maintenance

Research from the Cleveland Clinic has found that your brain processes an average of 70,000 thoughts per day. Your daily thoughts are occurring in the midst of the 500 trillion neuron connections in your brain, which themselves need to be updated every night. Neuroscientists have also found that the average person is consuming about 74 gigabytes (GBs) of data every day, and this amount is growing by five percent each year.

That’s a serious amount of information to sift through! As you can see, your brain is a sophisticated mechanism that needs sufficient rest and recovery every 24 hours. Sleep is your brain’s one chance each day to solidify new things you learned that day, get rid of unnecessary information, and refresh itself for new learning the next day.

Sleep is crucial to maintain and grow your cognitive capacity. Here’s what great sleep helps your mind with:

  • Stronger concentration. Sleep is your mind’s repair shop, and science shows us that your brain cells shrink during sleep to make waste removal easier. Without this complicated, automatic waste removal process, you won’t be able to concentrate well the next day.
  • Improved problem-solving skills. Problem-solving includes being able to assess a variety of information sources in a given circumstance and identify the best path forward. This is much harder to do when you’re groggy or stressed. Sufficient rest every night boosts this area of comprehension and helps you face whatever you’re working on.
  • Clearer thinking in general. Waking up with that “refreshed” feeling is the result of getting not just enough sleep, but the right type of sleep. Clear thinking means your brain had enough time to remove all of the cellular waste it accumulated the day prior.

After just one week of poor quality sleep, your ability to think quickly and concisely starts to slow down. That’s why it’s essential to learn how to sleep better, including the best temperature to sleep in and how much sleep to get every night.

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Frequently Asked Questions About Primary Sleep Functions

Now that you’ve learned the answers to, “What are the main functions of sleep?” chances are you have even more questions than you originally thought. Figuring out how to get better sleep without a lot more work can be a maze of information at times.

We looked up the most commonly asked questions about the main functions of sleep so you don’t have to. Check out the questions and our answers below:

What are the Three Purposes of Sleep?

Sleep has much more than three purposes, but if you had to narrow it down to three, it would be physical rest and recovery, improving mental clarity and function, and the creation of new neural pathways and connections (including memories). Getting rest that promotes these healthy functions allows you to wake up the next day and address it with precision and energy.

What Are the 4 Benefits of Sleep?

Sleep has more than four benefits, but if you had to narrow it down to just four, it would be strong cognitive function, memory development and retention, mood and emotional regulation, and balanced energy. The lack of proper functioning in these areas is the most noticeable if you haven’t gotten good sleep.

What are at Least 2 Reasons Why Sleep Is Important?

There are dozens of reasons why sleep is important, but the top two are mental and physical recovery. Your brain processes dozens of gigabytes’ worth of material every day and much of it is not necessary for the next day. In order to keep what’s helpful and discard what’s useless, your brain uses a sophisticated cellular waste removal system.

Sleep is the one time of day your body has a chance to recover from activities and injuries. Your body uses sleep to send nutrients to wounded muscles and tendons, reduce inflamed tissue with increased blood flow, and reoxygenate muscles for decreased soreness.

How Is Sleep Defined In Psychology?

In the psychological fields, sleep is defined as a partial or total suspension of consciousness that’s accompanied by sensory limitations and voluntary muscle inhibitions. The lack of movement and temporary sensory deactivations is what makes it possible to rest and recover without being distracted.

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What Is the Most Important Form of Sleep?

The most important form of sleep is deep sleep. While you should strive to get a full night’s sleep every day, if you have to prioritize one type, it’s definitely deep sleep. This is non-REM sleep during which your body is replacing cells, repairing them, and handling the grunt work it can’t do while you’re awake.

Want the perfect mattress to enjoy all of your incredible sleep on? We have you covered, and not just with mattresses, but pillows and sheets too. Shop our mattresses now and reach out to us with any questions.

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