First 422 words of the document:
Outline and evaluate restoration explanations of the functions of sleep. (24 Marks)
The restoration theory suggests that the function of sleep is to repair and restore the brain and
Oswald (1980) suggested that different types of sleep are necessary for restoring different
biological functions. REM is needed for brain growth, repair and reorganisation; during REM
sleep, sleep patterns of REM brain activity allow these changes to happen. He suggested that
SWS is necessary for bodily growth and repair; during SWS, growth hormones are released.
Horne (1988) suggested that there were two types of sleep; core (REM) and optional (SWS).
Brain restoration and repair take place during core sleep, and bodily restoration takes places
during optional sleep but also occur at other times, such as, during periods of relaxed
The restoration theory predicts:
o Deficits in functioning when sleep deprived, and cause negative effects on bodily
o REM sleep is increased when the brain is growing or undergoing reorganisation.
o Sleep will increase when the body is growing or undergoing repair.
o People attempt to catch up on sleep when sleep deprived.
o `Rebound' effects following sleep deprivation.
P: REM rebound effect has been demonstrated
E: To achieve REM sleep deprivation, researchers woke sleeping volunteers as soon as their
eyes began to dart about. They found that people showed an increased tendency to go into
REM sleep once they went to sleep, and the proportion of time spent in REM sleep increase
50% higher than normal.
C: This is strength of the theory because it proves that the rebound effect does occur.
S: However, the sample used was volunteers could be biased.
P: There is evidence for the role of sleep as restoration.
E: Shapiro et al found that marathon runners slept for about an hour more on the two nights
following the race.
C: This supports the idea that NREM sleep appears to be more associated with physical
S: However, the sample used here were only marathon runners which means it is not
generalisable to the whole population.
P: There is evidence that lack of sleep has fatal consequences.
E: Rechtschaffen et al forced rats to remain physically active, but after 33 days, all sleep
deprived rats died.
C: However, this is not generalisable to humans as it was tested on animals.
Other pages in this set
Here's a taster:
S: Furthermore, this was ethically incorrect as the animals died.
P: There is evidence against the idea that lack of sleep has fatal consequences.
E: Rattenborg et al conduced a similar experiment but with pigeons, and the pigeons suffered
no ill effects.
C: As this was conducted on animals, it is not generalisable to humans because animals have
different sleeping patterns and needs to humans.…read more