What is sleep?

Sleep is the regular period of rest in every 24 hours, when humans and other animals are unconscious and unaware of their own surroundings. As humans, we need different amounts of sleep depending upon our age – babies need many more hours than a healthy teenager for example.
Why do we need to sleep? Despite us spending a third of our lives asleep, doctors and researchers still do not know the actual purpose of sleep. But what they believe is:
Sleep helps us repair the cells in our body
  Whilst we are at rest and in a deep sleep our use of energy is much lower; this energy conservation seems to give us the opportunity to repair our bodies and recharge our batteries.
Sleep helps us conserve energy
  When we are asleep our need for energy to live and interact with our environment reduces, compared with our needs when we are awake.
Sleep helps us form and retain our memories
  Complex processes are involved in helping us to process and store sensory information into memories. Such sensory information is obtained from all of our senses, such as from what we see, hear, taste, touch or smell.
Sleep helps support our immune system
  Poor sleep can make us more vulnerable to viruses which cause the common cold or influenza.
Overall, good quality and good quantity sleep leaves us refreshed and fully restored to function efficiently and remain wakeful the next day. In fact, studies have shown a direct link between the amount and quality of sleep and our abilities to function the next day. People with insomnia are more likely than people who can sleep well to have an accident or be less productive at work (due to absenteeism, reduced concentration or difficulty performing tasks).

References

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