Discuss the nature of sleep, including two explanations of the functions of sleep
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Introduction
Discuss the nature of sleep, including two explanations of the functions of sleep The restoration theory of sleep involves sleeping to recover, repair and to grow. Oswald stated that REM sleep is needed to replenish neurotransmitters in the brain and help the brain recover, while NREM sleep is used to restore bodily processes and functions. Oswald also said that sleep restores energy, removes waste from the body and repairs cells. There is a lot of empirical evidence to support this, for example babies undergo far more REM sleep compared to an adult - this can be explained because of the amount of energy a growing brain requires due to increased protein synthesis for cellular growth; this study has high ecological validity because it is a naturalistic experiment and it can also be generalised to all babies as they all undergo large amounts of REM sleep. ...read more.
Middle
The restoration theory relies heavily on the biological approach which has empirical evidence to support this, but it does not explain any of the cognitive processes or how peoples experience's affect sleep. It does not talk about the differences of sleep between cultures, but it is possible that there is no difference between cultures. It also shows that the nature of sleep is deterministic in the way that we can't control our requirement of more or less sleep. The evolutionary theory of sleep states that the way we sleep is due to changes in our body so that we are best adapted to the environment. It refers back to prehistoric times when it was difficult to survive due to lack of food or threat of predation. Meddis suggested that one of the reasons why we sleep is for protection (predation theory) ...read more.
Conclusion
The evolutionary theory is backed up by plenty of evidence and is based on science, but we are unable to go back in time and find out what prehistoric life was like so this theory is based on assumptions, which also means cause and effect cannot be implied. The theory is also not reductionist because it thinks about multiple meanings of sleep. Evolutionary theories are unable to explain the complexities of sleep or why we can die from lack of sleep so it does not offer a full approach to the nature of sleep. We are now much more advanced, food is readily available and we are able to protect ourselves at night, so sleep would be pointless according to the evolutionary theory, however there is a possibility of the genome lag and that it would take a long time to adapt to our need for less sleep. ?? ?? ?? ?? ...read more.
This student written piece of work is one of many that can be found in our AS and A Level Physiological Psychology section.
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Here's what a teacher thought of this essay
This ends with a reasonable point. The essay lacks any kind of conclusion that would draw together the first and second half and reach a decision on which theory of sleep is most likely to be accepted. A conclusion might state that some kind of combination of the three explanations would be more useful - that we sleep to conserve energy during crucial restoration processes, and that this has the added benefit of keeping us out of harm's way.
This essay doesn't really yscrape under the surface of why we sleep, so 3 stars.
Marked by teacher Jo Wilcox 10/04/2012