1. For Tuesday 1.Read and make notes on content for sleep disorders- Highlight/Annotate your pack We will have a short quiz on these and then evaluate Have a nice bank holiday

2. Function of sleep

3. Starter – Lifespan and sleep Write a short email Use theory, research and evaluation 1.Write a short email to Chris Thomson arguing for Bhasvic’s timetable to be changed Use atleast one piece of evidence Can you include an IDA point?

4. Knowledge quiz: lifespan changes 1. What is the % of Rem sleep at each stage? Babies (50-60%) Older children (25%) Adolescents (20%) Adulthood (25%) 60’s (20%) 70/80’s (10%) 2. At what lifespan stage do you experience phase advance? People in the 60’s 3. At what lifespan stage do you experience phase delay? Adolescence 4. How many hours of sleep a night are needed at each stage? Babies (16h) Older children (12h) Adolescents (9-10h) Adulthood (8h)

5. Knowledge quiz: lifespan changes 5. When does our circadian rhythm become established? 6 months of age 6. At what two stages in our life are sleep disorders common? Older children and adulthood 7. At what stage in the lifespan is there no stage 3 or 4 sleep? Individual in their 90’s

6. Functions of sleep The Specification 1.Restoration explanations 2.Evolutionary explanations Both include discussion of impact of sleep deprivation Aim of this session : Outline Restoration explanations of sleep Ground and evaluate research into the functions of sleep Evaluate Restoration explanations for the functions of sleep- Next lesson we will class debate

7. Restoration explanations Read the proposals by Oswald (1980) and Horne (1988) Summarise what they suggest about the function of sleep in two sentences

8. Example Oswald suggested that NREM sleep (SWS) was vital for restoration of the body and REM sleep for restoration of the brain. Horne concluded that sleep did not necessarily involve body restoration but was essential for brain restoration, with major roles for REM and deep NREM (SWS or stage 4) Restoration theories Horne (1988) Oswald (1966) “Every stage of sleep is essential for restoration!” “No! Only SWS4 and REM are essential for restoration!”

9. Sleep Deprivation- Peter Tripp P20 Make notes and ground in pack

10. Research activity 1.What does this suggest about the Function of sleep? 2.Which explanation does this support (Oswold? Horne? Both? Why?)

11. Randy Gardner- (1964) In 1965, an American student, Randy Gardner, aged 17, stayed awake for 260 hours (11 days). The effects of sleep deprivation on Gardner were less extreme than on Peter Tripp but still included moodiness, problems with concentration and memory, paranoia and hallucinations. After four days, he had the delusion that he was a famous American football player winning the Rose Bowl. He also mistook a street sign for a person. On the 11th day, he was asked to subtract seven repeatedly, starting from 100. He stopped when he got to 65... and said he had forgotten what he was doing. He had no significant psychotic symptoms and appeared perfectly normal after a lengthy sleep.

12. Michael Cork- Fatal Familial Insomnia FFI: Inherited condition in which people sleep normally until middle age and then simply stop sleeping even though they want to. Death usually follows within two years and is associated with damage to the thalamus He slept fine all his life until one day, shortly after his 40th birthday in 1991, Corke began having trouble sleeping. In the following weeks, his sleeplessness grew worse and his health deteriorated. Eventually he was plagued by total insomnia - he could not sleep at all. Doctors were baffled by Corke's condition and he was diagnosed with Multiple Sclerosis, even though insomnia is not a symptom of MS. Nobody understood why he couldn't sleep, or why sleeping pills and barbiturates made it worse. Tragically, Michael Corke died in hospital after six months of total sleep deprivation.

13. Dement (1960 Which function of sleep explanation does this study support? Why? Are there any relevant evaluation points to make for this study? (Add to the bottom of your handout)

14. Sharpio at al (1981) Runners in a marathon slept for about an hour more on the two nights following the race and SWS (stage 4) particularly increased. Empson (1989) Found that the disruption of stage 4 in healthy people resulted in stiffness in the back and muscle pain

15. Benington and Frank (2003) Conducted research with Rats Found that rats slept longer following completing learning tasks Suggests that sleep has a role in the function of Long term memory Crick and Mitchison proposed that during REM sleep unwanted memories are discarded, meaning we only have the memories we really need, making our brain more ‘efficient’.

16. MWB- List three pieces of evidence we have looked at for restoration 1.Swap your whiteboards 2.Identify an appropriate Ao3 research evaluation point 3.Explain why this is an evaluation point and remember to link to sleep

17. Application and Evaluation Prince’s death Currently there is a lot of discussion in the media around Prince’s death and the possible causes Read the article- Highlight and Annotate 1.Use theory/evidence to support/challenge the claims that are made about the possible cause of his death 2.Use further knowledge/evaluation (IDA?) to support/challenge the argument made

18. Research evaluation Case study- Generalisation- Problem because we know individual differences effect sleep (e.g life stages) / studies have shown individual differences in terms of sleep stages. Limits our understanding as cannot apply individual case studies to a wider population (external validity) Lab studies- Artificial and low ecological validity. This is a problem because an artificial environment would not reflect true sleeping environments therefore sleep may be disrupted thus affecting the validity of the results and understanding of the function of sleep Lab studies- High control means can use scientific equipment to evidence brain waves and stages of sleep within sleep cycles aiding our understanding of the importance of sleep and the impact of sleep deprivation

19. IDA – Restorative Functions of Sleep Group task Write an IDA on the wallboards based on the following points 1.Reductionism- Strength/ benefits 2.Reductionism- Limitations/ implications 3.The Biological approach- Strength/benefits 4.The Biological approach- Limiations/implications

20. IDA Template The restoration theory is Reductionist because ____________________________________ ____________________________ The is a strength/ limitation of the approach as ____________________________________ ____________________________________ ____________________________________ This means ____________________________________ ____________________________________ ___________________________________

21. IDA Template The restoration explanations of sleep adopt a biological approach as it suggests………. This is useful/a problem because……. This means that…………..

22. Restorative functions of sleep “The restoration approach focuses on physiological processes in brain and body, a low level, simplistic and therefore reductionist explanation. It does not take into account evolutionary explanations and ecological factors such as predator- prey status which have been shown to influence sleeping patterns and great differences in sleep patterns across species. This means this explanation may be incomplete as it does not consider the complexity of sleep including, individual and cultural differences”

23. Further (Wider) Evaluation Other IDA? Biological/reductionism/ determinism Research method Evaluation? Case studies/labs/animals Useful Applications- understand sleep deprivation important implications for health Support from lifespan- Infant REM sleep The fact that babies spend more time in REM sleep suggests the need for sleep is to help with brain growth and development. Brain Trauma Patients who have suffered brain trauma spend more time in REM to repair and restore cognitive functioning. Conflicting evidence However! Lavie (1984) reported on a 3 3 yr old whose head had been injured by shrapnel at age 20 and thereafter experienced almost no REM sleep. This did not appear to have serious side effects and he completed his education and practiced law. Cognitive sense Makes sense in light of the psychological and behavioural effects of sleep deprivation.

24. Essay: consider the consequences of disrupting sleep Mark and improve This is a C grade – Ao1 4/4 A02/3: 7/16 What have they done to achieve a C? How could they improve this?

25. Evolutionary Theory The functions of sleep

26. IDA: starter Individually on mwb write an IDA point for the restoration theory of sleep.

27. IDA Template The restoration theory is Reductionist because The is a strength/ limitation of the approach as This means… The restoration explanations of sleep adopt a biological approach as it suggests………. This is useful/a problem because……. This means that…………..

28. Starter: essay: consider the consequences of disrupting sleep Mark and improve This is a C grade – Ao1 4/4 A02/3: 7/16 What have they done to achieve a C? How could they improve this?

29. Evolutionary Explanations Explain each- do not use packs 1. Energy conservation (Webb ) Mammals expend a lot of energy just staying awake at a certain body temperature. We have a limited supply of energy so sleep acts as a way of reducing the amount of energy we use up each day as it is a period of ‘enforced inactivity’. Also, this can explain why some animals sleep more than others; smaller animals have a greater need for saving energy as their metabolism is higher, hence why they sleep more. Webb called this the ‘hibernation theory’ of sleep. 2. Foraging requirements This explanation can help us understand why some animals spend more time sleeping than others. Herbivores eat food which is low in nutrients, so in order to get the nutrients their bodies’ need they need to spend more time eating, and therefore spend less time sleeping. This could explain why some animals sleep much longer than others.

30. Evolutionary Explanations Explain each- do not use packs 3. Predator avoidance ‘Predator avoidance’ is another way in which we can understand why some animals sleep more than others. If an animal is a predator it doesn’t have to worry about being attacked while it sleep, so it can sleep for long periods of time, conversely prey must spend as much time as they can afford to awake in order to avoid predators. 4. ‘Waste of time’ According to Meddis, sleep ensures that animals stay still and out of the way of predators when they have nothing better to do, so sleep is simply a way of wasting time. Seigel agrees with this view, saying that actually being awake and moving is more dangerous for prey as the animal is more likely to get injured.

31. Evolutionary vs Restoration What is the difference? Discuss Evolutionary theory suggests sleep is not vital but it is important from what it prevents us from doing. Restoration suggests it is vital

32. Sleep deprivation and Evaluation How do the sleep deprivation studies challenge the evolutionary explanations of sleep? Helpful hint : Fails to explain

33. Examiners report- Outline and Evaluate Evolutionary Explanations of sleep ( 4 + 16) Many students wrote too much for this question. Popular explanations were energy conservation, predation, ‘waste of time’ and foraging patterns. Studies could usually be quoted, and some better answers focused on inconsistencies in results, eg metabolic rate and sleep time. Better responses discussed the possible separate functions of rapid eye movement (REM) sleep and slow wave sleep (SWS), and focused comparison with restoration explanations. Less successful students were sometimes diverted into the classic single case studies of sleep deprivation without making them relevant to the question.

34. Examiners report- Outline and Evaluate Evolutionary Explanations of sleep ( 4 + 16) Effective IDA included the problems of extrapolating from animals to humans, given the nature of human social and cultural evolution. Less effective was a discussion of free will in relation to rabbit sleep patterns. Many answers referred to the sloth as being a problem for body weight/metabolic rate hypotheses of sleep time, as they are large and yet sleep for 20 hours a day. However, we have known for some years that in the wild the sloth sleeps far less than in captivity, about nine hours (Rattenborg et al., 2008).

35. IDA: The issue of generalising findings from animals to humans.

36. The Evolutionary Approach and understanding sleep The Evolutionary approach is problematic due to the issue of generalising findings from animals to humans. Evolutionary approaches emphasise ecological niches for non-human animals (how animals respond to their natural environments), while humans have radically altered the nature of theirs over the last few centuries, so it is likely that conclusions derived from non-human animals would not apply to humans. This questions the validity and usefulness of the explanation and limits our understanding of the sleep of humans in contemporary society. Complete pages 23/24

37. Complete pack Pages 23/24

38. Create an essay plan Outline and evaluate one or more explanations of the functions of sleep (8 +16 marks)

39. Plenary Watch the video Make notes Write down any “new” content / studies to add width/ breadth to your knowledge https://www.youtube.com/watch?v=3mufsteNrTI

40. Complete all the following 1.Outline one example of an Infradian rhythm (4 marks) 2.Outline lifespan changes in sleep (4 marks) 3.Outline the nature of sleep (8 marks)

41. For Tuesday 1.Read and make notes on content for sleep disorders- Highlight/Annotate your pack We will have a short quiz on these and then evaluate Have a nice bank holiday