Restoration Theory

Question 1

Generally, what is the restoration theory about?

Answer 1

Sleep being a period of rejuvenation and repair

Question 2

Why is sleep thought to be a period of rejuvenation and repair?

Answer 2

Important biological functions take place, restoring biological system to a better working order

Question 3

What are the 2 slightly different versions of restoration theory?

Answer 3

1) Oswald (1980)

2) Horne (1988)

Question 4

Outline the different functions of different types of sleep according to Oswald (1980)

Answer 4

SWS in body repair

REM in brain recovery

Question 5

Summarise Oswald (1980)

Answer 5

Sleep helps to reverse or restore biochemical and physiological processes that are progressively degraded during the day

Question 6

How do we know about the different functions of different types of sleep?

Answer 6

SWS - increased growth hormone production during the 4 stages which indicate bodily restoration and repair
REM - high levels of brain activity during REM indicates brain restoration

Question 7

Why is the production of growth hormones during SWS important?

Answer 7

Particularly important during childhood, and also important in adulthood as proteins are fragile and constantly need to be renewed

Question 8

When is growth hormone released?

Answer 8

It is released in pulses during the day but more at night

Question 9

Name 2 research studies which support the idea that SWS is associated with the production of growth hormone?

Answer 9

1) Sassin (1969)

2) Krueger (1985)

Question 10

Outline Sassin (1969)

Answer 10

Found that when sleep waking cycles reversed (i.e. sleep in the morning) the release of growth hormone is also reversed showing that growth hormone release is controlled by neural mechanisms relating to SWS

Question 11

Explain one bit of evidence supporting the idea that SWS is associated with the production of growth hormone

Answer 11

The amount of growth hormone released correlates with the amount of SWS and the decline in growth hormone in older age has been associated with reduced SWS

Question 12

Outline Krueger (1985)

Answer 12

Lack of SWS is associated with reduced functioning of the immune system as antibodies (proteins) are regenerated during cell growth and protein synthesis in SWS

Question 13

Explain one bit of evidence supporting the idea that REM is associated with brain recovery

Answer 13

The % of active/REM is a lot higher in babies than adults and even higher in premature babies as they need rapid brain growth - it has been suggested that the amount of REM is proportional to the immaturity of the offspring at birth

Question 14

Name 3 research studies supporting the association of brain recovery with REM

Answer 14

1) Siegel (2003)
2) Siegel & Rogawski (1988)
3) Crick & Mitchison (1983)

Question 15

Outline Siegel (2003)

Answer 15

Platypus are immature at birth and have 8 hours of REM whereas a dolphin can swim at birth and has almost no REM, suggesting a relationship between neural development and REM

Question 16

Outline Siegel & Rogawski (1988)

Answer 16

Suggest REM allows a break in neurotransmitter release which in turn permits neurons to regain sensitivity and body function properly - support from MAOIs which are drugs that increase neurotransmitters with the side effect of abolishing REM completely suggesting increased monomines means monomine receptors don’t have to be revitalised and so no need for REM

Question 17

Outline Crick & Mitchison (1983)

Answer 17

Proposed in REM, unwanted memories are discarded making more important memories accessible but recent, more complex relationship - REM procedural memory whereas SWS for semantic & episodic memory

Question 18

Name 7 bits of evidence for Oswald (1980)

Answer 18

1) Sassin (1969)
2) Krueger (1985)
3) GH correlating with amount SWS & old age
4) % REM in babies
5) Siegel (2003)
6) Siegel & Rogawski (1988)
7) Crick & Mitchison (1983)

Question 19

What are 3 positive evaluative points for Oswald (1980)?

Answer 19

1) If sleep has a restorative effect, then sleep deprivation should have clear consequences - Rechtschaffen (1983)
2) REM rebound - Empson (2002)
3) The effect of increased physical exercise - Shapiro (1981)

Question 20

Outline Rechtschaffen (1983)

Answer 20

Forced rats to remain physically active by rotating a disc they were on every time they started to go to sleep, After 33 days, all sleep-deprived rats died

Question 21

What does Rechtschaffen (1983) show?

Answer 21

That sleep is necessary for life and thus suggests that sleep has a restorative effect

Question 22

What are 4 negative points about Rechtschaffen (1983)?

Answer 22

1) Possible that stress direct cause of death
2) Ethical issues
3) Generalisability
4) Rattenborg (2005) similar experiment with pigeons who suffered no ill effects suggesting it is different across species

Question 23

Explain the REM rebound in relation to Oswald (1980)

Answer 23

Sleep deprivation may lead to REM rebound - Empson (2002) woke ppts when eyes started to dart about (REM) and found increased tendency into REM when back to sleep and on recovery nights, proportion spent in REM increased with rebound being as much as 50% higher than normal

Question 24

Explain the effect of physical exercise in relation to Oswald (1980)

Answer 24

Increased physical exercise should lead to increased sleep in order to restore proteins and biochemical used - Shapiro (1981) found long-distance athletes after 56 mile race, slept an hour longer for 2 nights with increased SWS suggesting does aid restoration and NREM associated more with physical recovery

Question 25

Name & explain 2 negative points about Oswald (1980)

Answer 25

1) Peter Tripp and Randy Gardner suffered no long-term damage and had no need to recover the amount of sleep lost
2) General research has found that extensive exercise does little more than make you fall asleep faster - Horne & Minard (1985) gave ppts exhausting tasks but didn’t increase sleep duration, only went to sleep faster

Question 26

Outline Horne (1988) theory

Answer 26

Known as the core sleep model - many restorative processes occur when awake so sleep not provide repair function but core sleep essential for restoration but other types known as optional sleep whose purpose is energy conservation - stage 4 and REM necessary for healthy brain functioning

Question 27

Name 6 pieces of evidence for Horne (1988)

Answer 27

1) Horne (1988)
2) Jouvet (1967)
3) Everson (1989)
4) Peter Tripp
5) Randy Gardner
6) REM rebound

Question 28

Outline Horne (1988) support

Answer 28

Amino acids form proteins that come from food so if amino acids make proteins during SWS, we would need to go to bed within 5 hours of eating as this is how long they stay in the body, but we don’t so goes against Oswald of SWS necessary for protein synthesis, so must happen when awake

Question 29

Outline Jouvet (1967)

Answer 29

Cats on flower pots on water, could balance and enter stages 1-4 but in REM, muscles relax, fall in and wake up - deprived of REM, they died after 35 days so supports Horne as REM necessary but not stage 1-4

Question 30

Name 3 negative points about Jouvet (1967)

Answer 30

1) Does not explain why REM necessary btu stages 1-4 not
2) Ethical issues
3) Generalisability

Question 31

Outline Everson (1989)

Answer 31

Found sleep deprived rats had an increased metabolic rate, lost weight, and died in 19 days possibly due to immune system damage - suggests necessary for restoration

Question 32

Name a big negative of Everson (1989)

Answer 32

It could have been stress that caused the death of the rats and not sleep deprivation

Question 33

Outline Peter Tripp

Answer 33

Stayed awake for 201 hours - 3 days into it became unpleasant & abusive, 5 days began to hallucinate & paranoid, his body temperature continuously declined but after 24 hours sleep, returned to normal

Question 34

Outline Randy Gardner

Answer 34

Stayed awake for 260 hours but there was no significant psychotic symptoms and normal after a lengthy sleep - does not support restoration theory

Question 35

Explain REM rebound in relation to Horne (1988)

Answer 35

When Tripp & Gardner went to sleep, they had a REM rebound suggesting that REM sleep is the restorative part

Question 36

What are 4 positive evaluative points about restoration theory?

Answer 36

1) Patients with brain trauma have increased REM suggesting repair & restoration
2) Young infants sleep lots for rapid brain and body tissue growth
3) Fatal familial insomnia - cannot sleep & usually die within 2 years
4) Peter Tripp - body began to degrade suggesting sleep does have a restorative function

Question 37

What is the problem with looking at fatal familial insomnia with restoration theory?

Answer 37

There are very few cases and it is difficult to generalise from with sufferers having brain damage that may be responsible for death

Question 38

Name 6 negative evaluative points about restoration theory

Answer 38

1) Animal studies - ethical issues & generalisability
2) Evidence based on case studies & observational studies of small groups so cannot generalise as individuals may be unique (those trouble sleeping less likely to volunteer) - unrepresentative population
3) Randy Gardner - no ill effects
4) Reductionist as fails to consider non-biological factors
5) Horne & Minard (1985) - fall asleep quicker after physical exertion but not for longer
6) Sleep is universal but varies considerably - dolphins no REM but if restoration vital, why? So environment taken account of, nature interacting with nurture

Question 39

Name and explain one IDA point for restoration theory

Answer 39

The evolutionary approach as an alternative - can explain why dolphins have no REM - process of evolution - environmental pressures leading to differences in sleep patterns - Young (2008)

Question 40

Outline Young (2008)

Answer 40

Suggests more we know about sleep pattern of other species, the more apparent it is that environmental pressures provide the key to understanding sleep