What are Hypnic Jerks?

Hypnic Jerks: Why We Twitch While Falling Asleep

Have you ever been almost asleep, only to jerk awake with all of your muscles seeming to fire at once? While these hypnic jerks can be uncomfortable and unsettling, they’re usually nothing to worry about. Here’s everything you need to know about what they are, why you have them, and what you can do to minimize your chances of experiencing them.

What Is a Hypnic Jerk?

A hypnic jerk occurs when you’re in the hypnagogic state, which is the state between waking and sleeping. You are resting peacefully, then your body has a massive muscle spasm. You may flail, though some people only twitch. Afterwards, you may go directly back to sleep or you may be awake for a while, unsettled by the whole experience. A few people scream involuntarily, so don’t be surprised if this happens to you.

Many people feel like they are falling when they experience hypnic jerks, while others feel like they are dreaming or hallucinating. A few feel like the jerk is preceded by a loud noise or a bright light that comes from inside their head.

Up to 70% of people experience hypnic jerks at some point in their lives, so they are fairly normal. Most people don’t find them too disturbing, though some can’t go back to sleep for quite a while after experiencing one.

Why Do We Experience Hypnic Jerks?

There hasn’t been a lot of research done on hypnic jerks. They seem to be exacerbated by the use of caffeine too close to bedtime, too much alcohol, exercise late at night, and stress. In addition, being fatigued or sleep-deprived seems to raise your chances of experiencing a jerk, too. However, scientists can’t say that any of these things definitely cause them.

There are various theories out there about why we experience this phenomenon. Some theorists say that the nerves simply misfire on their way from being awake to being asleep. This may happen more often in people who are overtired or whose brains are overstimulated.

Others say that the experience of hypnic jerks has evolutionary origins. They say that our body misinterprets our muscles relaxing as we fall asleep for what happens when we fall out of a tree. The whole body tightens in order to minimize the damage of the fall. This corresponds well with the falling sensation that often accompanies hypnic jerks.  However, it doesn’t make sense of the sensations of light and noise that so often accompany the phenomenon.

In the end, there’s no definitive answer to why we experience hypnic jerks. Since they aren’t usually dangerous and they don’t disrupt sleep very much for the majority of people, they have often been deemed unworthy of further study.

How Can We Minimize or Stop Hypnic Jerks?



Since there’s no definitive answer as far as what causes hypnic jerks, it’s hard to know exactly what will stop them. Most people find that determining what causes the jerks, for them, and then eliminating that from their lives is the most helpful.

Look at the list above of things that correlate with hypnic jerks. See if any of them are present in your life. Are you anxious? Do you tend to lay in bed at night worrying about the day you had or the day to come? Do you consume caffeine or alcohol late at night? Maybe you have an unusual sleep schedule. Are you sleep deprived right now?

Continue through the list until you figure out which factors may be causing your hypnic jerks. Then do what you need to do to eliminate those things from your life. If your hypnic jerks get better, then you now know how to manage them for yourself. If they don’t get better, keep addressing your sleep until they do.

You may not be able to eliminate hypnic jerks entirely. However, you can usually do something to limit your experience with them. If they are especially disturbing for you, it will be worthwhile to make sure you’re getting enough sleep and have good sleep hygiene. Soon, you should experience fewer jerks and get better rest.

How much sleep is enough?

How Much Sleep Do You Really Need?

It’s easy to say that sleep deprivation is an epidemic, but much harder to figure out how much more we actually need to sleep every night. While average numbers are nice, we are all individuals. Some people legitimately need more sleep than others, and most of us need different amounts of sleep at different times. So how much sleep do you really need, and how can you figure it out?

Standard Recommendations for Sleep

Most experts will tell you that healthy adults need 7-9 hours of sleep every night. That’s what numerous studies have shown. These results have been replicated, repeated, and confirmed over and over again.

Some people feel like they need more sleep than that because they’ve built up a sleep debt that they haven’t paid off. Over time, if you’re not getting enough sleep, your body craves more than this average amount of sleep in an effort to get back the sleep that it has lost.

Even if you look at the standard recommendation without factoring in sleep debt, that’s still a two-hour gap! If someone who needs 9 hours of sleep every night only gets 7, that person will be building up sleep debt rapidly. They won’t feel rested, and they’ll struggle through their days. So how can you determine how much sleep you need?

Determining Your Ideal Sleep Amount



The amount of sleep you need is actually determined by many factors, including your age, your body’s innate need for sleep, your sleep quality, any medical conditions you’re fighting, how much you exercise, and whether or not you’re pregnant. Thus, the amount of sleep you need is likely to vary throughout your lifetime.

If you want to determine how much sleep you need right now, there are a few things to think about.

How Do You Wake Up?

When you wake up in the morning, how do you feel? Are you up slightly before your alarm, ready to get dressed and take on the day? Or do you have to drag yourself out of bed every morning, wishing there was some way you could shut your eyes again for just a few more minutes?

The way you wake up says a lot about whether you’re getting enough sleep. If you wake up happy and ready to get up, you’re probably getting enough sleep. If you struggle to wake up, require an alarm clock to even have a chance of getting out of bed, and sometimes miss your wake up completely, you likely aren’t getting enough sleep.

How Do You Fall Asleep?

How long does it take you to fall asleep at night? If you lie down, think for 20-30 minutes, then rest, you’re probably just the right amount of tired. On the other hand, if you crash the minute your head hits the pillow, then it’s likely that you’re not getting enough sleep.

If it takes you longer than 30 minutes to fall asleep every single night, you may be getting enough sleep but this may also have other causes. Are you feeling anxious? Are you overtired, or did you drink caffeine too late in the day? Before you decide you’re getting plenty of sleep, rule out these other options.

How Tired Are You During the Day?

If you bounce out of bed ready to take on the world but you want to nap by 10 AM, you’re probably not getting enough sleep. Take some time to focus on how you feel during the day, every day. It helps to write down how much you slept, how you felt when you woke up, and how you feel throughout the day. It may sound silly, but writing it all down can help you determine whether you’re really getting enough rest.

Look, too, at how well your body functions. Are you hungry all the time but gaining weight, too? Your body may be struggling with metabolic issues due to sleep deprivation. Do you get sluggish at a certain time of day? Your body may be trying to tell you that you need more sleep.

Determine Your Ideal Bedtime

Another way to determine how much sleep you need is to take a couple of weeks and figure out your ideal bedtime. Decide when you need to get up, then count backward 7 hours from there. That’s the time you need to be asleep. Do your best to fall asleep at that time for a few days.

If you’re tired, and you probably are, push your bedtime back by 15 minutes. Keep doing this every few nights until you’re waking up ready to go, falling asleep in 20-30 minutes, and feeling good during the day.

When you reach that point, congratulations! You know exactly how much sleep you need at this point in your life. Remember that you can always do this exercise again if you feel like your sleep needs change.

Sleep Deprivation

What Happens When You’re Sleep Deprived?

At least one-third of Americans are sleep deprived. This means that they’re sleeping less than 7-9 hours a day. Considering the effects that sleep deprivation can have, this is a significant and scary number of people who are trying to live, work, drive, and function while very, very tired.

At its most basic, being sleep deprived means that you aren’t getting enough sleep. It means that you aren’t spending enough time in bed, eyes closed, heartbeat and respiration rate lowered. And it means that your body is not getting to do all of the things it needs to do while you sleep.

What are the Effects of Sleep Deprivation on the Body?

Sleep deprivation doesn’t just make us feel exhausted and irritable, it actually has some negative effects on the body. Here are just a few of the ways that sleep can keep us from living our best lives.

Sleep Deprivation Causes Unstable Blood Sugar and Weight Gain

When we’re tired, we want more energy. The way the body usually gets energy, while awake, is by eating. Thus, when we’re tired, our bodies actually consume more calories than they do when we’re well-rested. All of those extra calories have to go somewhere, and they tend to stick to the body as extra pounds.

Sleep Deprivation Harms the Immune System

When we sleep, we make necessary parts of our immune system’s fighting system. When we don’t get enough sleep, we don’t have time to make as many of these as we need to effectively fight of disease. Many of these substances also keep systemic inflammation down. When this rises, we are at higher risk for heart disease and autoimmune diseases, among others.

Sleep Deprivation Hurts the Brain

When we don’t sleep well, we don’t function well. We don’t make good choices and we aren’t able to react as well under pressure, and our attention tends to wander. We may also struggle with impulsivity. This is part of why drowsy driving is such a big problem!

In addition, sleep deprivation harms our mood. It correlates with higher levels of depression, suicidal thoughts, and paranoia.

How Do We Know if We’re Sleep Deprived?

It can be quite obvious when you’re sleep deprived. You’ll not only feel tired all day but sleepy, too. You may actually fall asleep in inappropriate places, like in class or during important meetings. You’ll probably yawn a lot, and you might be down, discouraged, or moody.

The effects of sleep deprivation can also hide, though. If you’re more clumsy than usual, or you are having trouble losing weight, or you’re making poor decisions and you’re not sure why make sure you’re getting enough rest. All of these can happen when you don’t get enough sleep.

What Can We Do About Sleep Deprivation?



Some cases of sleep deprivation are caused by an underlying condition. These include but are not limited to Restless Legs Syndrome, narcolepsy, and sleep apnea. If you suspect that you have one of these conditions or you’re trying to get good sleep and it’s not working, see your doctor to start the process of diagnosis. Left untreated, these conditions can cause chronic sleep deprivation. Once they’re treated, though, you will likely sleep more, and better.

If you don’t have an underlying condition, look at your sleep hygiene. Make sure you are making it likely that you’ll sleep well through your actions and your environment. Good sleep hygiene can include:

  • Setting specific times for waking up and falling asleep…and sticking to the schedule!
  • Avoiding screens that emit blue light, or blocking the blue light, for 1-2 hours before bedtime
  • Making a bedtime routine that is comforting and relaxing
  • Ensuring that your pillow and mattress support your body well and feel comfortable, according to your sleep position and your desires
  • Making your room and immediate environment as dark and silent as possible
  • Exercising regularly, though probably not right before bed
  • Avoiding foods that are excessively fatty or rich, or ones that tend to upset your stomach
  • Refraining from naps longer than 20-30 minutes during the day, even when you’re tired

Putting these into practice could make falling asleep drastically easier for you. Make sure, too, that you have enough time to sleep. If you need to, give up an activity or change your habits so you have time to fall asleep, sleep for your desired amount of time, and wake up slowly. Without the time, the habits won’t matter at all.

Sleep deprivation may be an epidemic, but it’s one we can stop. When we seek treatment for the conditions that keep us from sleep and clean up our sleep hygiene, we will sleep more. This will make us safer, happier, healthier, and more stable, both as individuals and as a culture.

Sleep Paralysis

Sleep Paralysis: Awake in a Nightmare

Have you ever found, either while falling asleep or waking up, that you can’t move your body? Maybe you were both inside a dream and outside of it, unable to move or defend yourself. Sleep paralysis can be scary, but it’s not something you need to be too worried about.

What is Sleep Paralysis?

Sleep paralysis is just what it sounds like – the inability to move your body while you’re asleep. In this temporary state, you can’t move your muscles, react, or speak.

Sleep paralysis generally goes along with REM sleep. In this sleep state, we experience most of our dreams. It makes sense that we can’t move, so we don’t disrupt our partners, hurt ourselves, or get in some kind of trouble while acting out a dream. Thus, sleep paralysis protects us from ourselves.

However, sleep paralysis can spill over into the periods where we are just falling asleep or just waking up. This is when it scares us because we can’t move or speak when we think we should be able to. Sometimes, the dreams spill over, too, so we confuse our waking and sleeping worlds.

People who struggle with sleep paralysis as they are falling asleep are simply remaining alert as the body gets ready to enter REM sleep. This is called predormital or hypanogic sleep paralysis. Those who struggle with it as they are waking have post-dormital or hypnopompic sleep paralysis. They are alert and awake before their REM cycle is completed.

What Causes Sleep Paralysis?

Most people who experience sleep paralysis are genetically predisposed to it. This means that it can run in families. If someone you’re related to has problems with it, you are more likely to struggle, too.

Sleep deprivation can also cause sleep paralysis. When you’re excessively tired, your brain struggles when it moves in and out of sleep. It’s harder to make these transitions cleanly when your brain is exhausted, so it may confuse waking and sleeping more often.

People who have migraines, anxiety, sleep apnea, and narcolepsy are all more likely to have bouts of sleep paralysis. Researchers aren’t entirely sure why these conditions cause sleep paralysis, but people with them are definitely more likely to struggle with it.

Sleep paralysis may be caused by extra vigilance somewhere in the mid-brain. Many people who experience the condition wake up in a panic, sure that there is someone in the room or that they are in danger and cannot fend it off. Somehow, the vigilant part of the brain senses danger and wakes the person, even while the dream state and paralysis continue. Researchers are looking deeper into this mechanism, to see if they can tie sleep paralysis more closely to this anxious response.

What are the Symptoms of Sleep Paralysis?



When in a state of sleep paralysis, a person is unable to move. They may also see what seem to be visions, which are their dreams extending into waking life. These sessions can last a few seconds, a few minutes or, very occasionally, a few hours.

The person will feel like they cannot move, but they are not completely paralyzed. In fact, their eyes continue to move during these episodes, even if the rest of the body, including the vocal cords, cannot function as usual.

How is Sleep Paralysis Treated?

Treatments for sleep paralysis generally involve treating the condition underlying the paralysis. This means seeing a doctor about treating sleep apnea, migraines, anxiety, or narcolepsy. If there is no underlying condition, then sleep deprivation itself must be treated.

Treating sleep deprivation can be complex. It usually helps to improve a patient’s sleep hygiene or the conditions under which they attempt to sleep. This treatment can include:

  • Going to bed and rising at the same time every day
  • Planning plenty of time for adequate sleep
  • Making the bedroom as dark and as soundproof as possible
  • Getting a comfortable and supportive mattress and pillow
  • Exercising regularly
  • Not eating heavy foods before bed

If these things do not help improve a person’s sleep, he or she should speak to a doctor about medication. While medication designed to help you sleep has many side effects, it can be a helpful, short-term way to improve rest and, thus, lower the number of times a person experiences sleep paralysis.

What are the Other Effects of Sleep Paralysis?

Sleep paralysis is not a dangerous condition, but the panic that it causes can make a person afraid to sleep. If someone is so anxious about how they will wake up that they aren’t able to fall asleep or sleep deeply, it can disrupt their sleep routine and, ironically, make the whole problem worse.

Fortunately, most of us don’t have to struggle with sleep paralysis. Once we treat the conditions that underlie it, the problem tends to disappear or get reduced to manageable levels.

Why do we need sleep?

Why Do We Need Sleep?

There’s a lot more to sleep than meets the eye. Sure, it looks easy and it’s more-or-less easy to do, but there’s still a lot we don’t yet know about sleep. Scientists are studying it all the time, and we are learning more and more.

However, we still don’t have a definitive answer to one of the most basic questions: Why do we need to sleep?

We Do Need Sleep

One of the things that research has shown over and over is that human beings don’t function well without sleep. When we don’t get enough of it, we suffer. Our brains don’t work as well. We can’t regulate our moods like we usually can. We feel hungry all the time, and we crave food that isn’t good for us. Our metabolisms slow, our hearts don’t work as well, we aren’t as strong or as fast, our sex-drive disappears, and we are more likely to get sick.

It’s pretty clear that enough sleep is an absolute necessity if we have any chance of thriving as human beings. But why do we need sleep so much? What goes on while we sleep that is so important to nearly every bodily system?

Theories About Why We Sleep

Over the years, scientists and other theorists have come up with many ideas for why we sleep. Some of the more interesting are developed below.

Evolution and Sleep



One interesting theory relies on evolutionary success to explain why we sleep. Theorists who ascribe to this theory believe that we sleep because, back in the evolutionary chain, creatures who slept were out of harm’s way during the dangerous nighttime hours.

Think about it: nighttime had to be dangerous for prehistoric man and for other diurnal creatures. Predators would be out and no one would be able to see them coming. It would be easy for accidents to happen, too, since creatures who were awake and moving around wouldn’t be able to see as well as they would during the day. Thus, creatures who hunkered down and were quiet at night would be more likely to survive and would pass this trait on to their children.

Physical Restoration and Sleep

There is evidence that the body repairs itself while we sleep. Our tissues repair themselves, our muscles grow, we make proteins, and we release growth hormones during sleep. Some of these things only happen while we sleep.

In addition, creatures that are completely deprived of sleep lose immune function entirely, usually dying within a matter of only a few weeks.

Some theorists point to these results and say that this rejuvenation isn’t coincidental but is, in fact, the very reason that we sleep. We sleep because that’s when the body can rest, fight disease, and restore itself.

Brain Growth and Sleep

Sleep is essential for the growing brains of babies and young children. Babies spend an inordinate amount of time asleep, and much of that is in REM sleep when they’re dreaming. As we get older, we spend less and less time in REM. It seems that this sort of sleep is somehow necessary to the brain producing enough neurons, culling the ones that it doesn’t need or want, and allowing it to develop as it should.

While we can’t deprive babies of sleep in the name of research, all we have to do is look at the effects of sleep deprivation on older people to get a clue as to what REM sleep offers. People who are sleep deprived struggle to learn new tasks, and they even struggle to perform their current ones with their usual ease. Just look at how hard it is for people to drive when they’re tired! Clearly, sleep does something for the human brain that cannot be achieved without rest.


We may not know exactly why people sleep, but we do know that it’s necessary. Research continues on the topic for a few reasons. First, figuring out why we were meant to sleep may help us learn to sleep better. Since sleep deprivation is running rampant in the world right now, this research promises to help a lot of people.

Studying why we sleep may also help us figure out how to counteract the effects of sleep deprivation. For instance, if we find that cell rejuvenation is one of the key reasons why we sleep, we may be able to determine which chemical reactions are involved in that process. If we can produce these in a different way, then we won’t have to depend on sleep so much.

In the end, though, studying why we sleep is fascinating. If you think about it, the fact that we spend nearly one-third of our lives unconscious is a little weird. It’s natural that we want to know why we do this.

Understanding Circadian Rhythms

Does your body run according to certain patterns? Maybe you’re always ready for bed at 9:00 PM or you feel like you need a nap every afternoon. These are both examples of your circadian rhythms at work. However, these complex bodily systems manage more than just sleep and wakefulness. In fact, researchers are learning more and more about circadian rhythms all the time.

What is a circadian rhythm?

A circadian rhythm is any pattern in your body that follows a daily cycle. These can be physical, behavioral, mental, or psychological. Nearly all living things studied thus far have some sort of circadian rhythm. This includes animals, plants, and microorganisms, too. Circadian rhythms seem to be related to cycles of light and dark that come with day and night.

Is a circadian rhythm the same as a biological clock?

Your biological clock is how your body tells time internally. You may not always know exactly what time it is on the external clock, but your body is always tracking the time of day and what should be going on based on what time it is.

Nearly every organism studied so far has a biological clock. Individual tissues and organs seem to have them, too, though whether these are truly independent remains to be researched.

Your biological clock runs or drives your circadian rhythms, but is not identical with them.

How do circadian rhythms work?

Researchers are still studying the exact method by which circadian rhythms work. They know that the biological clock is managed by a structure in the brain called the suprachiasmatic nucleus (SCN). This is made up of over 20,000 neurons and is located in the hypothalamus. It interacts with the eyes, thus getting direct knowledge of what the external light is doing. This structure functions as a sort of master clock for the entire body.

The SCN, in turn, seems to direct certain proteins in the body. These bind to cells or don’t bind to cells, which tells them what to do or not do. At different times of day, these proteins interact with cells differently. This seems to set the circadian rhythms.  

What do circadian rhythms control?

Circadian rhythms control when we sleep and when we wake up. They also play a part in controlling when we release certain hormones, when we feel hungry and how and when we digest our food, and our body temperature, which goes up or down based on the time of day. Circadian rhythms can also affect our energy levels, causing many people to need rest or food in order to keep going through the middle of the afternoon.

How do we make our circadian rhythms?

We don’t have a lot of choices as far as the circadian rhythms the body sets. The determining factor seems to be whether or not particular types of light are present. Light and the lack thereof trigger certain genes to turn off or on. These genes control our internal biological clock, which then controls the body. As cycles of light and dark change, both biological clocks and circadian rhythms can be made faster, slower, or even reset entirely.

How do circadian rhythms affect health?

When our biological clocks are too fast or too slow, our circadian rhythms get off balance, too. Disrupted rhythms are closely associated with health problems including depression, obesity, bipolar disorder, and diabetes. While researchers don’t know exactly how a disrupted clock helps cause these problems, it definitely seems to play a part.

What do circadian rhythms have to do with sleep?



Circadian rhythms are one of the basic mechanisms that tell us when to sleep and when to wake. The SCN tells the body to produce melatonin, a hormone that helps us sleep, when there is less light reaching the eyes. It limits melatonin production when there is plenty of light.

Some people, like shift workers, manage to disrupt this cycle long term. Researchers are studying what goes on in their brains to allow that. They are also studying how the light from electronic devices mimics sunlight and lowers melatonin production.

How do circadian rhythms help us recover from jet lag?

Jet lag happens when our biological clocks and circadian rhythms get out of sync because of travel. Light comes in through the eyes when the body doesn’t expect it, or it doesn’t come in when the body does expect it. Either way, we feel sleepy at the wrong times and generally disoriented. Since the circadian rhythms can be reset by light, they slowly help us recover our equilibrium.

Circadian rhythms are complex, and the emerging research on them is fascinating. As we learn more about how the body manages its circadian rhythms, we may also learn more about how we can get more sleep, better rest, and how we can care for ourselves well.

The Stages of Sleep – What Happens While You’re Sleeping

You may think you’re at perfect peace when you sleep, but the truth is that your brain is active. In fact, your brain and your body move in and out of several different stages of sleep through the night. Each has different characteristics, so scientists can always tell what stage a person is in, especially if the sleeper’s brain waves are being monitored.

Altogether, there are five stages of sleep. Four of these, Stages 1-4, are non-REM sleep. The last one is REM sleep. Most people cycle through these throughout the night, about once every 90 minutes. However, you spend more time in different stages at different times of night, and each person’s sleep cycles are slightly different.

Want to learn more? Here are the stages we all go through when we sleep.

Stage 1

This is the lightest stage of sleep. You can drift in and out of stage 1 sleep and may have the sensation that you can’t possibly keep your eyes open any longer. You are basically transitioning into true sleep.

In Stage 1, your body is beginning to slow down. Your brain waves are slightly slower than they are when you’re awake, but otherwise not much has changed there. Your respiration rate and heart rate will begin to slow down, though your body temperature remains the same as it was before.

The body’s muscles retain some tension in Stage 1, though they begin to relax. If you have ever experienced the sensation of falling and twitched yourself awake, that happens in Stage 1 sleep. Stage 1 usually lasts for 10 minutes or less, and it’s easy to wake up from this sleep. In fact, many people woken during Stage 1 don’t think that they actually slept at all.

Stage 2

Stage 2 sleep is a continuation of Stage 1. The brain waves slow significantly, though they usually show some instances of heightened, flurried activity. Eye movement ceases, and the heart and lungs slow even more. The body’s temperature also begins to fall during Stage 2, further preparing for deep sleep.

During Stage 2, most people are still fairly easy to waken. They can answer the phone straight out of sleep and still be coherent enough that the person on the other end may not be able to guess that they were sleeping at all.

You spend most of your night in Stage 2 sleep, passing through it every time you move from lighter to heavier sleep and back again. In fact, some people spend as much as half the night here.

Stages 3 & 4



Stages 3 and 4 together make up deep sleep. The brain waves here have slowed significantly from their usual daytime patterns, forming the long, slow waves that scientists call delta waves. In Stage 3, these waves can be broken up by smaller, faster waves, while Stage 4 is characterized exclusively by delta waves.

In these stages, your heart and respiration rates have slowed as much as they’re going to, which is usually a significant change from where they are when you’re awake.

People who wake up during these stages of sleep often become groggy and even confused. They may be very hard to rouse, requiring you to touch them or shake them rather than just talk to them. These are the stages where people experience night terrors, sleepwalking, and more.

REM Sleep

REM sleep is different from the other stages of sleep in that the brain becomes more active, sometimes as active as it is during the day. However, the body is paralyzed during this sleep cycle. It’s probably a good thing since we tend to dream while we’re in REM sleep. The paralysis keeps us from acting out all of our dreams!

The rest of the body returns to a near-normal state, too. Both the heart rate and the respiration rate pick up again, and eye movement returns, too. Researchers aren’t sure exactly what the eyes are doing during REM sleep, though they posit that they may be moving along with a dream.

People who struggle with sleep apnea or other sleep disorders can struggle during REM sleep. Because their muscles are paralyzed, their airways can collapse completely. Many of them have trouble breathing after this happens, as they can’t fully restore the airways while asleep.

Most people experience more REM sleep as it gets closer to morning. This might be the reason why so many of us awaken straight from a dream.

Sleep is fascinating and more complex than most of us think. The more we begin to understand about when, how, and why we sleep, as well as what goes on while we sleep, the better we can become at making sure we are all getting the sleep we need.

How Sleep Works

How We Sleep

Sleeping people seem so peaceful. They look like they don’t have a care in the world, like their bodies are completely at rest. Underneath this placid surface, though, the body and the brain are working hard. A lot goes on when you’re asleep, even if you don’t realize it.

Falling Asleep

The process of falling asleep seems to involve two different processes in the brain. They each affect different parts of the brain but, together, these processes tell the brain when it’s time to sleep.

Circadian Rhythm

The first of these is the circadian rhythm. This is the body’s internal clock and the method by which the body regulates many functions, including sleep. It also plays a part in how we know when to eat, in the ways our energy rises and falls during the day, and the way we almost always have some idea of what time it is.

Certain parts of the brain are regulated by this process. Under the rule of the circadian rhythm, it doesn’t matter how long you’ve gone since you last slept. Instead, it matters what time it is in your body.

This is why jet lag can be so disruptive, because at least part of your brain wants to fall asleep when it’s bedtime, whether you’ve been up for 16 hours or 6.

Sleep Drive

The second process that helps you sleep is called your homeostatic sleep drive. This is the process that tells you to sleep after you’ve been awake for a certain amount of time. Scientists liken this process to an hourglass. For every hour you’re awake, sand drops through the glass. The more sand that’s gone through, the more you feel the need to sleep.

When your circadian rhythm and your sleep drive are telling you it’s time to rest, the neurotransmitters in your brain change. This causes your neurons to begin to fire differently, which eventually leads to sleep.

The Stages of Sleep



Once you’ve fallen asleep, your body goes through 4 stages of sleep. It cycles through these roughly once every 90 minutes, and most people get through 4 or 5 cycles every night. The first three stages make up non-REM sleep. REM sleep and non-REM sleep have very different brain wave patterns and activity patterns in your neurons.

Stage 1 Sleep

In Stage 1 sleep, you’re actually transitioning from being awake to being asleep. This stage only lasts for a few minutes. During it, your heartbeat begins to slow, as do your respiration rate and your eye movement. Your body also relaxes, though your muscles may twitch occasionally. Your brain shifts from its waking patterns to sleeping ones.

Stage 2 Sleep

This is an extension of Stage 1 sleep. Your heart rate and respiration rate slow even further, and your body temperature begins to drop. Your eyes stop moving altogether and your brain waves slow even more. There may be sudden bursts of electrical activity in the brain, but it is definitely moving toward deeper sleep. You spend most of your night in Stage 2 sleep.

Stage 3 Sleep

This is the deepest stage of sleep that you experience. Your heart rate and respiration rate are lower here than at any other time during the night, and your muscles are completely relaxed. This is the sleep that you need to have to feel well-rested in the morning, and it occurs in longer periods during the first half of the night.

REM Sleep

In REM sleep, your brain activity picks up again, even rivaling what it is when you’re wide awake. Your eyes twitch, though your muscles are paralyzed. You breathe quickly and the pattern may even become irregular, and your heart rate rises to nearly where it is when you’re awake. Most dreaming takes place in REM sleep. Periods of REM sleep increase during the second half of the night.

Why We Need Sleep



All of this is interesting, but what’s the point? Is there a reason we sleep, or did our bodies develop these weird patterns for no discernable purpose? Fortunately, sleep seems to serve several purposes.

Clearing Out Toxins

The brain and the body build up certain toxins during the day. These are generally byproducts of normal functioning and they won’t hurt you as long as they get cleaned out. This cleaning process happens while you’re asleep. Certain neurological diseases seem to correlate with a lack of sleep, and scientists believe that they may be a product of brains that don’t have time to clean themselves out properly.

Making Repairs

Your body repairs its tissues while you’re asleep. Some of these are things you might never notice, like micro tears in your muscles or damage on a cellular level. Major healing occurs during sleep, too. This is part of the reason why we feel extra tired when we’re sick or coming out of surgery. Without sleep, our self-repair becomes much less efficient.

Conserving Energy

Since both the breathing rate and the heart rate are lower during sleep than at other times of day, both the lungs and the heart get a bit of a rest. This not only saves you the energy of powering these organs at full blast 24/7, but it also means that they last longer and can repair themselves better. Since most of us want our heart and lungs to last a long time, getting plenty of sleep seems like a good idea!

Sleep isn’t only something we want to do, it’s something our bodies need us to do. Most of us, sadly, aren’t sleeping enough and our bodies are paying the price. It’s worth the effort to figure out how to get even a little more sleep, as the hours add up over time.

What is Sleep?

What is Sleep?

Sleep seems pretty basic, right? You close your eyes, your brain turns off for several hours, sometimes you dream and sometimes these dreams make sense, then you wake up and continue on with your life.

Scientists have found, though, that sleep is anything but basic. In fact, some parts of the brain are more active during sleep than they are when you’re awake. There is more to sleep than meets the eye, and more than anyone even knows.

Characteristics of Sleep

One way to define sleep is to look at the different characteristics it holds. Some of these are common sense things that we all know because we have slept and we’ve seen others sleep. Some, though, are complex and fascinating and have come as the product of painstaking research.

Sleep is characterized by:

  • Reduced activity. Even people who walk or talk in their sleep are less active than they are when they are awake.
  • A change in posture. Most people, and in fact most creatures, sleep lying down. While there is some variation in how they lie (elevated or not, and on their backs, sides, or stomachs), people across time and across cultures have most commonly slept this way. Some people can sleep in other positions, especially when they’re exhausted, but lying down is the easiest and most common way to sleep.
  • Being relatively easy to reverse. It’s pretty easy to wake up someone who is sleeping. Even if they are in a deep sleep and wake up groggy, they can be woken within just a few minutes. This makes sleep different than being in a coma or being knocked out. It even makes it different than hibernation.
  • A drop in blood pressure. Unless the body isn’t functioning well, blood pressure is almost always lower when we are asleep. This can partially be accounted for by the fact that there are fewer demands on the body when we’re sleeping, but the drop is consistent enough that there may be other causes, too.
  • Specific brain wave activity. Neurons in the brain seem to fire randomly while we are awake, and they are very active. When we sleep, though, our neurons slow down and begin to fire, when they fire, in specific and coordinated patterns. When we enter REM sleep, the neurons pick up their activity, sometimes becoming even more active than they are when we’re awake. As we exit REM sleep, the brain moves back into slow, regular patterns of firing.

While all of these are part of the current definition of sleep, the brain wave patterns are what scientists most often use to define the sleep state. When our neurons are firing in particular patterns, we are asleep. The rest of the time, we’re awake.

Neurotransmitters and Sleep

Neurotransmitters and Sleep

We can also define sleep by the set of neurotransmitters currently active in the brain. These brain chemicals change when we are asleep. Thus, sleeping or waking status can be determined by the set and balance of neurotransmitters currently active.

Scientists don’t understand exactly how this works, yet. What they do know is that these chemicals interact with neurons at the base of the brain, which act as a switch. They switch off the balance of neurotransmitters that keep us awake and begin to replace them with others, which help us sleep.

This may all tie back to a particular neurotransmitter called adenosine. This builds up in the body while we are awake. When it reaches a certain concentration, we begin to feel tired and feel the effects of not sleeping. As we sleep, this chemical breaks down until concentrations are low once again. Research has not shown definitively how this process works, but it does seem that part of the definition of sleep has to do with how much adenosine is currently in the bloodstream.

Researchers are always seeking to understand more about how our bodies work and the mechanisms by which we sleep. While the current answers to, “What is sleep?” leave something to be desired, science is pursuing some promising lines of research to add to our understanding and, hopefully, help us sleep better.

Off-gassing and getting rid of the new mattress smell

Off-gassing and Getting Rid of the New Mattress Smell

Many people love new mattresses, especially memory foam ones. These consistently rate high for everything from comfort to durability. One of the few complaints about them is that, when brand new, they can give off a “new mattress” smell for several weeks. In fact, any new mattress can have that problem.

This smell comes from some of the materials that make up the mattress, and it will go away by itself over time. Fortunately, some manufacturers have taken these complaints to heart and have constructed their mattresses to they are less likely to smell at all.

Why Do Mattresses Smell?

Mattresses smell because of a process called off-gassing. Certain chemicals contain components called volatile organic compounds, or VOCs. These are not stable and so they tend to break down rapidly under certain conditions. When they do this, they form gases that must then escape. These gases are what you smell when something smells new.

Many things go through an off-gassing process. That new car smell comes from off-gassing. So does the smell of a freshly painted room, the scent of your dryer sheets, and the odor of nail polish remover. This is a common process.  

When it comes to your mattress, most of these chemicals are in the foam that makes up your bed or in the adhesives used to hold the different layers of your bed together. Some are also in the fire retardant treatment that the government makes all mattresses go through. Common mattress chemicals that off-gas include benzene, methylene chloride, formaldehyde, and chlorofluorocarbons (CFCs).

Is Off-Gassing Dangerous?



The majority of people won’t experience any side effects from off-gassing. A few people will get headaches, and some may experience nausea, eye and throat irritation, or find that their asthma is triggered. These symptoms go away when the person goes away from the mattress, and they generally dissipate completely within a few weeks.

Some people feel nervous because some of the chemicals that off-gas are labeled as carcinogens. However, there’s no research showing that memory foam causes cancer or is toxic in any way. While it’s definitely a topic that needs more study, there are ways to avoid or get rid of the smell, and the chemicals, if you are worried about them.

Can You Avoid the Smell?

If you want to limit your chemical exposure or you just don’t want to deal with getting rid of the smell, start by looking for a mattress with a Certi-PUR certification. This organization tests mattresses and their seal means that a mattress uses very little or no VOCs. Their test also includes CFCs, phthalates, heavy metals, formaldehyde, and PBDEs, so your mattress will be free from those, as well.

Some people don’t believe that Certi-PUR goes far enough to make sure mattresses are safe. In that case, you can look for the Green Guard or Made Safe certifications. You can also look for Global Organic standard ratings on the materials making up your mattress, to ensure that chemicals were not added during the manufacturing process.

If you want to avoid the issue altogether, there are a few mattresses out there made of wool and/or cotton. These naturally avoid the whole off-gassing problem.

Can You Get Rid of the Smell?



Yes! If you are concerned about the effects of off-gassing on your health or you just don’t want to deal with the smell, there are many ways to get rid of it.

  • Air out your mattress. Let your new mattress sit in your garage or in a well-ventilated room for several days before you put any bedding on it or attempt to sleep on it. This will let the VOCs escape without any negative effects for you. Use a fan or a dehumidifier to hurry this process along.
  • Jump on your new mattress. I know, I know, your mom always told you NOT to jump on your bed. Well, here’s the exception. When you jump on your new bed, it will release VOCs faster than if you simply air it out. Make it into a game for your kids, if you like. And if you have too much dignity to jump, try pressing on it systematically instead.
  • Place several bowls of white vinegar around the room. These will absorb and neutralize the odor that off-gassing leaves behind. Of course, then you have to smell the vinegar. If that’s as bad or worse for you than the gases, put the vinegar out during the day, close the door, and open the windows. When you get home, dump out the vinegar. Hopefully, it will have absorbed enough gas that you won’t be bothered by the smell.
  • Spray the mattress with an enzyme spray. While these sprays were originally designed to remove nastier odors, like that of urine and vomit, from a mattress, they can help with off-gassing odors, too. Simply spray the mattress according to the directions on the bottle and wait a bit. The bad smell should get better quickly.
  • Set out several bowls of baking soda around the room. Just as baking soda absorbs bad odors in your refrigerator, it will do the same in your bedroom. This process will take a while, though, as your room is much larger than your fridge. Thus, this method is best when the mattress is in a room that doesn’t get used much, when you have several days to let the soda work, or when it is used in combination with some other methods.
  • Use activated charcoal to absorb the smell. You can buy this in bulk and place it in bowls, like the baking soda, or you can even use charcoal briquettes in a pinch. You can even place your bowls of charcoal under the bed, so you don’t risk spilling your charcoal everywhere.
  • Spray your bed with vodka, or a vodka-water combination. Vodka is a champ when it comes to odor removal. Simply choose an unflavored version, put it in a spray bottle, and spray your bed. If you’re not comfortable using pure vodka, dilute it with water first. As the alcohol evaporates, it will take the odors with it.
  • Wrap your mattress. Several companies claim to make mattress wraps or covers that will keep the gases in so that you don’t have to breathe them in or even smell them. Most of these are not certified and have not officially been tested, so you buy them at your own risk. If you’re concerned about mattress odor, though, they can offer you peace of mind.
  • Think before you buy. Memory foam is associated with more off-gassing and odor complaints than any other kind of bed. If you’re concerned, look at latex, innerspring, or hybrid beds instead.

Off-gassing is a natural process that occurs because of the materials used to make a mattress. It is probably not dangerous, but if you are concerned about the chemicals or having a bed that smells, look for a mattress with certifications or take the steps necessary to break VOCs down before you sleep on your bed.