The Science behind Sleep

“Sleeping is no mean art:  for its sake one must stay awake all day.” -Friedrich Nietzsche



(Image credit: dedmazay / 123RF Stock Photo)

We all require a good night’s sleep to wake up the next day to, go to school, to do our jobs, or even to carry out our everyday chores. Even animals require sleep (although they have different periods and patterns). The habit of sleeping is introduced to a person so early in his life (from birth) that, he doesn’t know why he does it, but just knows that he needs to lie down and rest when he is sleepy. The brain automatically tells a man that is time for him to rest and when he fights it, eventually the brain goes into hyper-mode but eventually forces the person to sleep. In this article we will see what sleep is, some interesting stuff that goes on while we are asleep (like dreams) and some useful tips to get a good night’s sleep after a tiring day.


Whenever we sleep, we are least aware or absolutely clueless about what goes on in our surroundings. This would probably lead us to conclude that our body and mind shuts down during this process. Interestingly, that is not the case. Our muscles rest during sleep, leaving extra oxygen to be pumped to the brain. This keeps the brain very much active, but it is the sub conscious part that runs the show. So what exactly is the purpose of sleeping? Read ahead.


Why do We Sleep?

This is the question which has baffled scientists for many centuries. People think that we sleep to restore energy after a day’s work. But experiments reveal that sleeping for even eight hours saves a minute amount of energy, about 50Kcal, which can be obtained even from a single piece of toast.


So, even if we don’t know what sleep is meant for, we certainly can conclude that it is not for saving energy for the body (not completely though). It is for a deeper cause. We sleep because it is essential to maintain our cognitive skills such as speech, memory, innovative and flexible thinking. So we can say that sleep is more crucial for brain development. A good night’s sleep helps a person to organize and archive his memories and get re-energized for the next day. It is also believed by some scientists that during sleep repair of muscles and tissues and replacement of ageing or dead cells takes place. So the next question would be what will happen if we don’t sleep properly?


What Happens if We Don’t Get Enough of Sleep?

Anyone who has done an all-nighter will know the answer to this question. Lack of sleep has major effects on a person’s mental awareness and causes irritability, forgetfulness, grumpiness etc. It becomes very difficult to concentrate and the attention span is substantially reduced just for losing one night’s sleep. Miss one night of sleep and you will be very irritable and short tempered the next day, miss two days of sleep and your mental condition deteriorates causing lack of concentration and the person is prone to make silly errors in judgement. Miss three days of sleep, and the mind desperately trying to recover, starts playing tricks on the body leading to hallucinations and the person loses grip on reality. Experiments done on lab mice show that they die if they are forced to stay awake for many days, proving that sleep is essential for life.


Interesting fact: Studies show that being awake for 17 hours gives us the effect of having 0.05% of alcohol level in our blood (two glasses of wine) which the legal drink-driving limit in the United Kingdom.


Also, lack of sleep causes grave outcomes in places where a high level of alertness is required and the ability to make quick decisions in response to rapidly changing situations. Investigations show that this has caused certain global events leading to massive life loss and destruction such as the Chernobyl Disaster, Three Mile Island and the Challenger shuttle explosion.


Apart from disturbing our brain functions, sleep loss also effects physical and emotional health. Research has shown that lack of sleep leads to a drastic rise in stress levels and increases blood pressure. Also, irregular sleep patterns causes Obesity”since the chemical hormones, which control our appetite and weight gain, are released during the sleep period. Let us look into detail how the brain behaves during sleep.


Brain Activity during Sleep:

The brain releases certain waves which are recorded by a device known as the electroencephalograph (EEG). It is observed that the brainwaves change during different activities. When a person is awake and relaxed, the brain generates “Alpha Waves” which have a frequency of 10 cycles per second. A person who is alert and active produces what are called “Beta Waves”which are two times faster. When a person sleeps, the brainwaves become much slower. “Theta Waves” occur at 7-3.5 cycles per second whereas the deeper and slower “Delta Waves” occur at frequencies lesser than 3.5 cycles per second. The lower the frequency implies deeper the person is in sleep. It is considered harder to wake a person who is in delta sleep.


These cycles do not occur in an order but occur in a pattern or in stages. The stages of a complete sleep cycle are given as follows

Stage 1: “Light Sleep”: During this phase, a person is half asleep and half awake. Muscle    activity reduces and slight involuntary twitching may occur. During this phase, the person can be awakened easily. This stage lasts for 4-5% of the sleep cycle.

Stage 2: “True Sleep: Within 20 minutes or so, we enter the main portion of our sleep cycle. The breathing pattern slows down and becomes deep, heart rate slows down, and body temperature drops slightly. This comprises of 45-55% of the sleep cycle.

Stages 3 and 4: “Deep Sleep”: During deep sleep, the brain begins to generate delta waves with large amplitudes. Breathing and heart rate slow down further and reach the lowest possible limit. This comprises about 15-20% of the sleep cycle. A person who is woken up during this period is often disoriented and takes a certain minutes to adjust. Children who experience bed-wetting, sleep-walking and night terrors often do it in this stage.

Stage 5: “REM Sleep”: This occurs at random points during our sleep. Suddenly, the brainwave levels speed up and come to wake levels. This causes a Rapid Eye Movement (REM), breathing becomes rapid and shallow, heart rate rises and our muscles are completely relaxed leading to twitching of eyes and other muscles. This often occurs three to five times a night and comprises about 20-25% of the sleep cycle. Dreaming occurs during this stage and a person awakened during a REM sleep can recall the dream vividly. Periods which don’t involve REM are called Non- Rapid Eye Movement (NREM) sleep.


The Ability to Dream:

During every 70 to 90 minutes gap, the brain stem sends a random electric impulse to the brain. The forebrain (the analytic part) then, desperately tries to analyse this random electric impulse to make sense out of it by creating a dream. This does not say that dreams are random, but in fact the way the brain perceives the impulse tells a lot about the person. The brain incorporates fine details to the dreams (like characters, props, scenes and environment) so that the random impulses start to make sense.

  • Almost all dreams are egocentric, meaning that they are centred on you.
  • You have almost no control in your dream whether it is a fantasy or a nightmare.
  • The surrounding noises are incorporated into the dream such that the brain is in sync with the ears creating a higher level of reality.
  • Dreams are important for analytical development of the brain and for emotional development. It is found that people who are not woken up during REM sleep often feel uncomfortable.


Tips to Sleep Better

The amount of sleep that you require is totally dependent on you. Your body will know how much sleep is best for you. The average sleeping time of a person is about 5-10 hours a day, where most adult people seem to need about seven to nine hours of sleep a day. A good night’s sleep ensures that you get proper brain development and develop a healthy immune system. Your ability to perform in whatever job you do will greatly be enhanced by following optimum sleeping schedules. Some tips to get a good night’s sleep are:

  • Exercising before sleeping ensures that you enter into a proper deep sleep as soon as possible and promotes muscle development.
  • Having a warm bath before going to bed can certainly help.
  • If you don’t feel like sleeping, indulge in a non-stressful activity such as solving a crossword, reading books, playing cards etc. Go back to bed only when you feel sleepy.
  • Caffeine should be avoided after 4pm as it can affect how fast you go to sleep.
  • Eating a light meal for dinner is important for sleeping well. If you feel the need for a midnight snack, bread or cereal is the best as it promotes a hormone called Serotonin” which helps you sleep well.
  • Create a regular habit of going to bed and waking up at the same time every day.
  • The Bedroom should only be meant for sleeping. Computers and Televisions cause distractions in your sleep patterns.
  • Alcohol must be avoided in the night as it primarily interferes with the nervous system i.e. the brain.
  • Studies show that the average person feels least alert during the day between 2-4pm. 15 minute naps can solve this problem. But we must be cautious not to nap beyond 20 minutes as we will enter a deep sleep after which we will feel drowsier.
  • If you feel that you still have a problem with snoring, it is advised that you visit a doctor who can further advice you specific to your sleep disorder. (read more natural ways to sleep blissfully)

 baby sleep

We, at ReadandDigest wish that you get a good night’s sleep and hope that you can “Sleep like a Baby”.