What is Sleep and why do we need to sleep?

What is sleep?

Although when we sleep, we tend to drift off into a nirvana of unconscious slumber, what most of us don’t realise is that our brains can actually be more active during this period in the day than any other. In fact, until the 1920s’ leading psychologists believed that both our bodies and our brains turned off during the sleeping process and were in fact completely inactive; somewhat similar to turning off a television set or computer.

It wasn’t until 1929 that scientists were able to record brain activity and discovered that way more was happening there than originally presumed. Recordings known as electroencephalograms (or EEGs for short) are able to show researchers just what was happening to the brain during periods of sleep.

Sleep itself can be defined as an unconscious period of reduced activity associated with lying down (though not in all animals) during a period of decreased responsiveness.


What happens when I sleep?

Whilst a person is sleeping, their body and mind undergo a series of dramatic and wonderful changes that helps refresh, relax and prepare them for the next day. For instance, there are many physiological changes that occur to the body during sleep. Temperatures, organ function, blood pressure and brain activity all change during different periods of sleep.

The most well-known activity during sleep occurs in the brain as it undergoes a series of fluctuating cycles that occur throughout the neurotransmitters. The most well-known phase of which is known as REM sleep and is the stage that is most associated with dreaming. During this stage there is an increase of firing neurons, even more so than when we are awake; making them increasingly random and varied. It is during this period of sleep that if woken, we are more likely to recall any dreams that we were having at the time. People who wake during deep sleep are more likely to report of having dreamt of nothing whatsoever.


How much sleep do I need?

The truth is – unlike what much of what the rest of the internet says – there is no solid amount of hours that you need to sleep; it totally depends on you. Some people need a good eight to nine hours of sleep in order to function like a normal human being the next day. Other people may however, get away with as little as five hours sleep and awake the next morning as fresh as a spring morning.

A study which was carried out in 2005 showed that the amount of sleep that a person needs varies among people, depending on how old they are, how healthy they are and what kind of life they live. Although you may think you may be able to get away with short periods of sleep, doing so has been linked to motor vehicle accidents, increased body mass index and risk of diabetes and heart problems.


What about naptime?

Unlike much of the western world, many tropical cultures do encourage taking naps during the afternoon. Quite often in countries such as Spain, shops and offices will close for a few hours in order for their inhabitants to have a few hours rest.

Biologically, the idea is not quite as outlandish as it sounds, as afternoon sleeping coincides with a lag in the body’s internal alert signal that offsets the bodies need to sleep throughout the day. This signal typically wanes throughout the warmest parts of the day and just after lunch time. Afternoon naps are therefore encouraged for a period of thirty to sixty minutes, though anything longer and you risk slipping into a deeper sleep may not be as refreshed when you awake. Take caution however, as too much sleep during the day can quite often lead to a disgruntled sleep during the night.


Myths about getting to sleep

There are a lot of myths surrounding the act of trying to get to sleep. Here are a few, though if you know for certain that they work for you, ignore this advice.

  • Alcohol – Unless you drink large amounts of alcohol before bedtime (enough to knock you out), alcohol can severely decrease sleep quality and interfere with your sleep patterns.
  • Counting – Though it may work for some people, counting generally keeps you more alert and is a tactic used by the armed services to keep personnel awake during operations and training.
  • Reading – The same goes for reading. Catching up with your favourite book before bedtime may be enjoyable, but it certainly makes you more alert. Try dosing off to a film.