What happens when you sleep? Nothing apparently. A few dreams, snores and nightmares, maybe.

Just like the tip of the iceberg, when we sleep we give rest only to our physical activity but there is a lot more going on. While the body and the conscious mind takes a rest, a new dimension of activities start doing their job.

How we fall asleep

Our sleeping happens gradually in stages. While you rest your head on a pillow and start to doze off, you enter the first stage of sleep called N1. This is the light kind of sleep and is the midway between being awake and asleep. Most of us have experienced this N1 catnap in boring lectures and long journeys which have made us doze off.

Scientists say that when we sleep, for the first 90 minutes we are in a kind of state which is called NREM (non-rapid eye movement). It starts with N1, deepens and we enter N2. In N2 we enter the ‘sleep’ mode. Our body temperature starts dropping. That is why sometimes we feel cold while sleeping. This is also why a cooler environment helps us fall asleep faster.

Gradually we enter N3 and deeper, and then after about 90 minutes we start the REM (rapid eye movement) sleep. On an average, REM happens for only one-fourth of our slumber time but it is very essential for us.

It is the N3 and REM stages that have shown weird and fascinating stuff to the scientists.

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What happens to your brain when you sleep

When we are awake, our brain is bombarded with thoughts and commands. As we know, our brain can work as well as much energy it receives. While we run and worry, the brain is working full time to fulfill our conscious needs. It is only when we sleep, it does its other jobs.

While we sleep, our brain does not. It has a lot to do:

# The brain processes all information we have gathered through all our senses. However, most of the information we gather is on an unconscious level. But we remember only a little of it because the brain at the time of sleeping looks into it and decides what to keep and what not. It decides what is important for us.

# While you nap, the brain will create your memories. It matches your thoughts, aspirations and state of mind and help you keep in mind some particular events that we would call as memory. Actually, the brain stores the rest of the data in the subconscious, kind of like a cloud storage.

# It throws out everything that is bad for us. Just like when we sleep the food gets digested to extract the nutrients and reject what is not needed – similar functions are run by the brain. The brain coordinates with various organs and rejects the toxins and the harmful stuff – in the mind as well as the body.

# It helps us heal and recover. While sleeping helps us build up our damaged tissues and bones, it also helps us recover from shock and trauma. The brain takes over and manages the body and the mind. That is people who have rested look fresher and better. Sleep deprived people start to experience many kinds of physical problems at first which then also lead to mental ones. A good sleep will shows on our face, eyes and skin.
While we snooze the brain will regulate the blood pressure, body temperature, pulse, heart rate, breath and body hormones – and causing it to change as it needs to relax the body and keep you sleep. Everything returns to normal state when we wake up.

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# It makes us remember how to do things. All that we have experienced and learnt in the waking state is gathered by the brain. Then it analyzes all that while we sleep and tell us how and what to do. The reason the brain chooses to do all this while we sleep is so that we have more energy to do our daily tasks. This also shows how important it is to have a good night’s sleep.

# The brain during the sleep solves our problems. Using the data and variables, the brain will work on solving our problems even while we sleep and are hardly aware of it. Sometimes we get the answers through our dreams. Our brain is really a highly complex machine.
There have been many instances of scientists claiming that they got their breakthroughs in dreams. Dmitri Mendeleev had said that he got the idea of the Periodic Table from his dreams. Today, we cannot imagine scientific study without this table.
German scientist August Kekulé solved a very complex problem of the structure of benzene in his dream. This went on to create a new area of study in organic chemistry.
The genius and one of world’s top mathematicians, Srinivasa Ramanujan accredited his thousands of formulas to dreams. Great scientists and researchers like René Descartes, Otto Loewi and Louis Agassiz and many more have accepted that they received many answers and solutions to scientific questions in their dreams.

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Weird things that happen when you sleep

While scientists keep on studying sleep and discover new benefits physiologically, there are also some weird happenings that they cannot explain. They have tried to speculate but for these events there are no solid explanations as such. Here are some of those weird things that happen or can happen when you sleep:

# Well first of all, it is weird that we still do not know what happens in our REM part of the sleep. Rapid Eye Movement or REM as the name indicates that when we reach that deepest part of the slumber our eyeballs move. Scientists have found no reason as to why the eyes would need to move when it shut and is in deep sleep.

# Sleep paralysis. This is one of those weird things that may happen to any one of us while we are sleep. Sleep paralysis is a condition when a person in sleep feels unable to move. He may get awakened but still feels immobilized and even unable to speak. It is a scary condition and it can last for a few seconds to minutes. The person feels helpless and scared, making it a disturbing experience.
In some cases, sleep paralysis is also accompanied by hypnagogic hallucinations and people believe that they have been attacked by supernatural entities.
Doctors say sleep paralysis is common among the people and most people have experienced it at least once. But in some people it aggravates into a serious disorder which can lead to other health and mental problems.

# Sleep drunkenness. Have you ever woken up from a slumber and forgot what day it was? Or forgot that you had woken up at midnight and totally forgot about it later?
Sleep drunkenness is also called confusion arousal because of this peculiarity. When you are woken up from the deepest phase of sleep like the REM, your brain takes time to ‘boot’ up. Sometimes, it simply forgoes the incident keeping no record of the memory.
Sleep drunkenness is not serious usually, and this confusion subsides in a few minutes. But if it seems to persist consult a doctor. Extreme cases of confusion arousal makes patients very irritable when woken up suddenly and they even become violent. In serious conditions, the confusion does not go away and the irritable feeling stays all day and even for a longer time.

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# Hypnagogic jerk. This is one of the most common and weird things we experience in our sleep. Do you not start to fall asleep and feel a shock like thing travelling through your body? The hypnagogic or hypnic jerk is a spasm that passes through your muscles and no one knows why it happens so.
We experience hypnic jerks when we shift from the asleep to the slumber state. But with the spasm, people also experience other things. They have experienced the feeling of falling down, feeling weightless and even hearing loud sounds out of nowhere. More than 70% of people regularly experience hypnic jerks making it a common yet very weird and unexplained phenomena.

# Sleepwalking and talking. It is estimated by the National Sleep Foundation that out of 100 people about 15 people sleepwalk or sleeptalk with no memory of it later. Sleepwalking can be simple like sitting or standing while in deep slumber. But sleepwalking takes a very weird and dangerous turn when activities become more complex. Sleepwalkers have been known to walk around, get down stairs and even drive cars. Sleepwalkers should be awakened immediately because they are not aware of what they are doing and can seriously harm themselves.
Sleeptalking can also get very weird at times. Sleeptalkers can go on to lengthy talks as if speaking to themselves or to someone else. As none of this activity is functioned by the conscious mind, they do not remember any of it when they wake up later.

# Sexsomnia. Doctors have tried to explain this weird activity psychologically and physiologically but no one knows for sure. Many men and women experience arousal and the experience of having sex very strongly while still in their slumber. Some people even carry on activities like masturbation in their sleep without remembering little or any of it later. This can become a disorder and may need doctor’s intervention.

# Sleeptexting. Weird as it may sound but it is true. People start to text while sleeping and have no memory of it. This is a relatively new phenomenon and this disorder is trending among the younger generation. The extreme affinity to mobile phones has pushed our brains into this disorder.

# Teeth clenching. More people do it in their sleep than they ever know. They clench or grind their teeth while asleep relating to a sleep related movement disorder called bruxism. Although it does not too serious yet over the period of time many complications can occur. As you may be unable to know if you have bruxism ask your partner to watch out of any symptoms.
However there are some effects you would start to notice if you suffer from bruxism. You may find that your teeth are getting flattened, loose or fractured and the tooth enamel is worn out. You may start experiencing stiffness in the jaw and dull headaches. The sensitivity or pain in your teeth and gums will increase. You may also experience a kind of earache but there is no problem with your ear. You may hear a clicking sound when you open and close the jaw.
In case of any symptoms, it is advisable to consult a dentist or doctor. Children have bruxism quite commonly and it may go away as they grow up.
Weirdly no one knows exactly why bruxism occurs. It has been attributed to stress, age, anger, epilepsy, sleep apnea and even Parkinson’s.

# We stop smelling while we sleep. There is no proper reason for this. It is assumed that the brain shuts down this function as it considers it unnecessary in our sleep time.

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# We listen. It sounds weird but we do listen to everything while we sleep. The brain takes in all the input and this is believed to be a survival strategy since our cave dwelling days. Primitive man had to depend upon sounds for their survival.
However the brain will not let sound interfere with the sleep. Only when it perceives danger or an emergency, then it alerts us to wake up.

# Night terrors. Somewhat like nightmares only more realistic. This weird phenomenon has been experienced by more by kids than adults but adults all over the world across all lifestyles have reported the feeling to night terrors. Night terrors will not let you sleep. People who have night terrors will cry and scream in their sleep and even run but they do not remember it later. Some people with night terror disorder cannot fall asleep at all.

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# Loud sounds and exploding heads. This weird and rare disorder makes people feel that a loud blast went inside their head just when they were dozing off. Generally stressed, sleep deprived and people who take coffee before bedtime experience the exploding head syndrome. They hear a very loud sound that wakes them up only to see that the sound came inside their head. Sometimes, they feel their head explode with a louder sound, making it an unpleasant experience.

# Shadow people. People in their sleep have reported what is called as shadow people. As the reports come in regularly from all over the world and across all age groups, it is considered quite a weird phenomenon. People who have seen shadow people while asleep or in a half sleep state talk about a grey humanoid entity. Many believe that these are ghosts or supernatural entity.

Seeing shadow people has also been accompanied often by sleep paralysis or night terrors. In worse cases, they feel being choked by these entities. Scientists are studying this occurrence and are deducing that it could be a case arising due to extreme stress or sleep deprivation.

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What happens to our soul when we sleep

It is widely believed, even by many psychologists, that we have an Out of Body Experience (OBE) while we sleep. This phenomenon is called Astral Projection.

People across the world believe that when we sleep, our soul moves freely. The soul is not bound by the gross body and while we sleep, it goes on a journey. However we do not die because of a light or silver coloured chord that attaches the soul to the body. The soul is capable of travelling at the speed of mind or more. It can transcend through time and space and travel across the universe and various dimensions. The soul cannot be harmed in any way. While we are still in deep sleep and the soul has its way, we experience some of its experiences as what we call as dreams.

When it is time to wake up, the soul or the consciousness returns to the body. Upon waking up we do not have any memory of it because none of it happened consciously. While we astral project, the body functions normally in the sleeping state without any hindrance.

Astral projection has been a topic of interest for many students of paranormal phenomena. Not only that, many psychologists who delve in past life regression and hypnosis support this as a valid occurrence which will someday be proved by science.

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