• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Discuss two theories of sleep.

Extracts from this document...


Discuss two theories of sleep. One theory of sleep is that it is needed for physical and psychological restoration and repair. Oswald 1966 said that sleep was needed for the restoration of cells and to restore energy levels. If Oswald's theory were true then you would expect sleep deprivation to have serious consequences, as the body would be unable to repair its self. You would also expect more sleep to be needed if more physical energy had been used. Oswald's study is supported by Rechtschaffen study on rat, as all the rats died after 33 days of sleep deprivation. Jouvet's study also supports this theory as the cats died when deprived of REM sleep. Although there is also evidence that goes against Oswald's theory, for example Randy Gardener went for 264 hours with out sleep, he suffered very few side effects and only needed an extra 7 hours of sleep to recover from his sleep deprivation. ...read more.


Although protein synthesis is said to take place during SWS and REM sleep protein is need and protein only lasts around 4 hours in the body. Sleep is also said to help physical restoration Hartmann 1973 found that people generally needed to sleep more during times of stress. It is also found that insomniacs tend to be very anxious, however it cannot be said that insomnia causes the anxiousness or the anxiousness causes the insomnia. Another theory of sleep is the evolutionary theory. This is based on the idea that all animals sleep, but they sleep different amounts and at different times, and go into different stages of sleep. The reason for this is said to be because sleep has evolved to fit the ecological niche to which the animal belongs. Meddis 1979 said that sleep has evolved to keep animals safe from predators, and to suit their needs and method of finding food. ...read more.


is used to keep the brain warm, as reptiles are cold blooded they don't need to do this so they have evolved to not dream. This theory does not explain why some animals don't fit the pattern, for example the giant sloth is large a slow yet sleeps for 20 hours a day. This theory also doesn't explain why humans still require so much sleep when it would clearly be and advantage to humans to evolve to need less sleep. There has not been much research to back up this theory as it is hard to back up any evolutionary theory, although it is not too far fetched to believe that animals evolving in this way, was to protect them from pray and to conserve energy. Horne 1988 suggested that different animals may have different uses for sleep and that there may not be a universal function of sleep that fits all animals. Faye Johnson 13.6 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Physiological Psychology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Physiological Psychology essays

  1. Marked by a teacher

    Describe and evaluate research into the stages of sleep

    4 star(s)

    For instance, he began to mistake objects for people. He also felt that some people were labelling him as stupid because of his impaired cognitive abilities. After he had finished and broke the record he slept for 14 hours and 40 minutes, then on subsequent nights he returned to his usual 8 hours per night.

  2. Describe 2 theories of the function of sleep and evaluate them in relation to ...

    This suggests that rest would be just as adaptive as sleeping. Further criticism would suggest that it would be safer for prey animals to rest and not sleep, as it does not come with certain dangers that sleep has, such as loss of consciousness, which further endangers the animals.

  1. Different People and their Sleep Needs.

    You should not feel any drowsiness or sleepiness during your day even if you are not participating in an activity. Sleep effects all your daily activities and your mental processes. Lack of sleep while driving can cause drowsiness, which has the same effect as driving under the influence.

  2. Dreams. There are no limits when dreaming.

    Normally one will not remember them unless one pays special attention to remember them. Even with special attention one only remembers some prominent features of their dream. The question of why we do not remember is as follows. If the function of dreaming is to wake up the sleeping brain

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work