1. Homework ~(due in 8th) Complete paper 2
(Biopsychology, research methods and approaches)
Folder/textbook check

2. Page 48 exam question Read through your own exam question on Robert
Highlight where the A01, A02 and A03 are and the PEEL structure within your A03 points
Read the model answer. Highlight on the essay anything that you have NOT included in your own essay

3. Objectives To be able to…
To outline biological rhythms: circadian rhythms
To outline and evaluate research into circadian rhythms
Apply the knowledge to short exam question and a 16 mark essay question

4. Essay focus
Discuss the role of endogenous pacemakers in the control of one or more biological rhythm (16 marks) Discuss research into circadian rhythms. In your answer refer to research evidence (16 marks)

5. Intro to Biological Rhythms
A biorhythm is a pattern of physiological or psychological processes which repeats itself over a specified period of time.
Circadian (latin circa= approximately, dian = 24 hrs)
(e.g sleep wake cycle)
Ultradian (ultra= greater (they occur more than 24 hrs)
e.g sleep cycles)
Infradian (infra= lower (occur less than every 24 hours)
( e.g menstrual cycle)

6. Circadian rhythms
These are rhythms that last 24 hours, such as the sleep wake cycle.
Circadian rhythms have a periodicity of one day (time between peak and next peak)
Our bodies have many other circadian rhythms:
temperature regulation
bowel regulation.

7. Define the key terms regarding circadian rhythms
Task 1
Define the key terms regarding circadian rhythms
Endogenous pacemakers
Exogenous zeitgebers
The sleep/wake cycle
Suprachiasmatic nucleus (SCN)
Melatonin
Light
Social cues/Non phonetic cues

8. Endogenous pacemakers
Internal body clocks that regulate many of our biological rhythms.
Exogenous zeitgebers
External cues in the environment that entrain our endogenous rhythms.
The sleep/wake cycle
A daily cycle of biological activity based on a 24-hour period (circadian rhythm).
Suprachiasmatic nucleus (SCN)
Tiny bundle of nerve cells located in the hypothalamus in each hemisphere of the brain. The primary endogenous pacemaker in mammals.
Melatonin
Produced by pineal gland at night, governs sleep/wake cycle. Production inhibited during periods of wakefulness.
Light
A zeitgeber in humans that can reset the main endogenous pacemaker (SCN) and plays a role in the sleep/wake cycle.
Social cues/Non phonetic cues
Schedules created by others, e.g. mealtimes and bedtimes.

9. What gives us our sense of time?
Exogenous Zeitgeber
Outside the body
External cues
(e.g. your alarm clock)
Environmental stimuli
(e.g. daylight, temperature change)
Social cues
Endogenous Pacemaker
Within the body
Specific bio-chemical changes
(e.g. melatonin, SCN, pineal gland)
The activity of these pacemakers
Is likely to be innate
Bio Rhthyms
Unit 4

10. Endogenous Pacemakers
small cluster of cells in our hypothalamus called the: Suprachiasmatic nucleus (SCN).
linked to our visual system
influenced by the amount of light we detect.
Bio Rhthyms
Unit 4

11. The Master!
Suprachiasmatic nucleus
Bio Rhthyms
Unit 4

12. Suprachiasmatic nucleus
This is the main endogenous pacemaker in mammals
Located above optic chiasm
Information about light and dark hits retina
This information goes to SCN
Then to pineal gland
This produces melatonin
Induces sleep
Bio Rhthyms
Unit 4

13. Activity 2
Read the information on Circadian rhythms and create a comic strip depicting the sleep-wake cycle

15. 24 Hours of Melatonin Secretion
What does the graph tell us about melatonin production?
Bio Rhthyms
Unit 4

16. Stop and think…
What impact does shift work have on the circadian rhythm?
Is modern society changing our circadian rhythm?
Do individuals who are blind have a 24 hour oscillation cycle?

17. Research
In pairs, look over the pieces of research in your pack (page 58/59).
What do the studies suggest about circadian rhythms?
Extension: What evaluation points can we draw from the research?

18. Suprachiasmatic nucleus
Using the following terms.
Write an outline for Circadian Rhythms
Pineal Gland
Endogenous Pacemaker
Internal
light
Temperature
Exogenous Zeitgebers
Melatonin
Suprachiasmatic nucleus

19. Research to support EZ and EP
Miles et al demonstrated how a blind man who had a circadian rhythm of 24.9 hours struggled to reduce his internal pace no matter what exogenous zeitgebers were used highlighting some biological clocks may be more ingrained and not influenced . Morgan

20. Aschoff and Wever
Aschoff and Wever found that a free-running cycle persisted with a sleep/wake cycle of 25 hours, therefore showing that light has an effect on controlling circadian rhythms (because they were not 24 hours when there was no light). The findings also show that there is an endogenous pacemaker because the participants had regular rhythms.

21. Circadian rhythms – practical applications Make three suggestions/recommendations based on the following

22. Circadian rhythms continued

23. Circadian rhythms Plenary/starter… 1. Circadian rhythms are driven by
This is called entrainment - setting the body clock to the right time
2. The master circadian pacemaker is
Our body clocks
3. The SCN is constantly reset by light
Sending messages about environmental light to the SCN
4. In mammals light cells in the eye act as detectors
The suprachiasmatic nuclei (SCN) found in the hypothalamus
5. The SCN uses this info to coordinate
the activity of the entire circadian system

24. Suprachiasmatic nucleus
Using the following terms.
Write an outline for Circadian Rhythms
Pineal Gland
Endogenous Pacemaker
Internal
light
Temperature
Exogenous Zeitgebers
Melatonin
Suprachiasmatic nucleus

25. Evidence – Michael Siffre’s (1962) cave study
2:28 approx
Whilst watching:
What was the purpose or aim of this study?
What does it suggest about circadian rhythms?
How useful is it as a piece of research on this?

26. Evaluation: methodology
Artificial light may affect the circadian rhythm in the same way as actual daylight, and in these early studies, artificial light sources were not eliminated so these may have influenced the biological rhythm.
Siffre, for example, used artificial light when he was awake and this was turned off when he was asleep, it is likely that this could have stimulated the production of cortisol and melatonin.
Therefore, artificial light is a confounding variable that possibly has an impact on the findings.

27. Over to you…
1. Read the Guardian article. Highlight any AO1 in one colour and any evaluative arguments (AO3) in a different colour.
Summarise the general arguments communicated in the article.
2. Using the sheet provided colour code the evaluation points by matching up, the point, the explanation and the elaboration/however.
3.Complete the exam questions on 61 (bottom two)

28. Why…?
Why is it useful to know about circadian rhythms and the sleep/wake cycle?

29. What are the Implications of research in to circadian rhythms for the economy?
The implications of psychological research for the economy relate to people’s ability to work effectively.
Research showing how to cope with sleep/wake cycles could be useful to companies whose productivity would increase if members of the workforce are better equipped to deal with shift work, or changing the shift work patterns to fit in with people’s biological rhythms.
Research has shown workers suffer reduced concentration at around 4am and during this circadian trough mistakes and accidents are more likely, companies could use this knowledge to their advantage and to avoid costly mistakes or accidents by perhaps giving colleagues a break at this time or working shifts around this time.

30. Evaluation Practical applications
Alstadhaug et al (2008) found migraine attacks have a circadian rhythm with peaks in attacks at midday
Also that changing the clocks affected larks and owls differently and that overall both changes had negative effects on mood and behaviour
Biological determinism
Actually there is research that shows that if you are
told you have to wake up earlier than usual it can
effect your stress hormones such as cortisol levels.
born et al (1999) found higher ACTH in P’s than
normal at the time they told they must rise.
Bio Rhthyms
Unit 4

31. Evaluation AO3
Using the sheet provided colour code the evaluation points by matching up, the point, the explanation and the elaboration/however.

32. Activity: Fill in the gaps to complete the evaluation point
Issue & debate
Activity: Fill in the gaps to complete the evaluation point
Point: The theory enables us to understand how both_______________and _____________ act together to control the rhythm.
Explain: This is is because the theory show that while ____________such as the role of the SCN largely control the rhythm, _____________, such as light, play a part in resetting (entraininig) the rhythm
Link?: The greater understanding that the theory gives us of how the circadian rhythm is controlled, may lead to _____________as it could help us to deal with people who have circadian rhythm disorders more effectively. It could also help us to minimise the unpleasant and harmful effects of_______________ and ___________________

33. Exam Question
Sam is a police officer. She has just started working the night shift and after a week, she finds she has difficulty sleeping during the day and is becoming tense and irritable. Sam is also worried that she is less alert during the night shift itself.
Using your knowledge of endogenous pacemakers and exogenous zeitgebers, explain Sam’s experience (4)

34. Exam answer
An endogenous pacemaker is an internal mechanism that controls circadian rhythms such as the sleep wake cycle. (1) Exogenous zeitgebers, such as light, are external factors that influence circadian rhythms. (1) As Sam has recently moved to a night shift, her biological rhythm of sleep is out of sync with the external cues, that is, she is trying to stay awake in the absence of light and go to sleep when exogenous zeitgebers are telling her to be alert and active. (1) Shift work can lead to disrupted sleep patterns, increased anxiety, decreased alertness and focus. It is particularly difficult to stay awake when our core body temperature is at its lowest, around 4 am. (1)

35. Plan an essay to the following question

36. Ultradian rhythms

37. Activity mind map everything you know about these areas (5 minutes)
Localisation of function
Hemispheric lateralisation
Broca’s area
Plasticity
Wernicke's area
Circadian rhythm
Functional recovery
EEG/ERP
FMRI

38. Homework A: Revise memory and attachment
B: Create flashcard for all content covered on Biopsychology
Wednesday: lunchtime go over paper 2 (AS)
Reminder: 29th October – you have a paper 1 exam

39. Objectives
To be able to describe what is meant by an ultradian rhythm.
To be able to outline and evaluate research into ultradian rhythms.
To be able to discuss practical applications of research into ultradian rhythms

40. Starter How long do you sleep? How often do you remember dreaming?
What happens when you have a nightmare?
Do you feel refreshed when you wake?
Do you get enough of it?

41. Ultradian Rhythms
A biological rhythm with a periodicity of less than one day
The change from SWS to REM and BRAC (basic rest activity cycle)
Food seeking behaviour
Urine production

42. Key details Ultradian rhythms last fewer than 24 hours
found in the pattern of human sleep.
Cycle alternates between REM and NREM
consists of five stages.
Starts at light sleep, progressing to deep sleep and then REM sleep, where brain waves speed up and dreaming occurs.
This repeats itself about every 90 minutes throughout the night.

43. Activity 1 Read the information on Ultradian rhythms (page 62- 63)
Draw the brain waves in the boxes on page 62. What state is the individual in when the waves occur (which wave occurs when you are awake (relaxed), awake (aroused), light sleep and deep sleep)
Complete the table outlining the main waves and features at each stage of sleep

44. Ultradian: More then 24 hours
Each cycle lasts approx. 90 minutes
To main sections (NREM and REM)
NREM (4 stages of SWS. Only in the first 2 cycles does the individual enter stage 3 and 4)
First 2 cycles: sleeper descends through light sleep into deep sleep then into REM
REM (final stage – increases in length as night progresses)
A complete sleep cycle goes through the four stages of NREM sleep before entering REM (Stage 5) and then repeating.

45. Packs away…
Using the key words, draw or cut and stick a visual representation of the ultradian rhyth,

46. Exam Question
Describe one ultradian rhythm (5)

47. Model Answer
Responses to this short answer question were often disappointing. The focus needed to be on ultradian rhythms, but many students were diverted into describing the stages of REM and NREM sleep in far too much detail. For full marks the focus needed to be on the patterning of the stages and the fact that the ‘sleep staircase’ repeats throughout the night in a rhythmic pattern.

48. Model Answer
An ultradian rhythm is one with a periodicity of less than 24 hours and the best example is the transition between SWS and REM during a nights sleep. Sleep has a 90 minute cycle and we have between four and six of these per night. We start in stage 1 sleep, which is very light and go deeper, through stages 2 and 3 until entering deep sleep in stage 4. This is also known as slow wave sleep as the brain waves have low frequency. We then go through stage 3 and 2 again before entering a stage of REM sleep. This lasts for around fifteen minutes and we are in a very deep sleep during this time. However our brain is as active as if we were awake. We then move back into stage 2 and the cycle begins again as we descend into stage 3 and back into stage 4

49. Research Dement and Kleitman (1957) Kleitman (1969) Ericsson (2006)
Peter Tripp

50. Evaluation
Evidence supports the idea of distinct stages in sleep (continued)
Process the results of the Dement & Kleitman study and describe one strength and one limitation of it.
Replications of this investigation have noted similar findings, though the small size of the original sample has been criticised.
Nevertheless, the study suggests that REM (dream) sleep is an important component of the ultradian sleep cycle.

51. Evaluation
Method
When investigating sleep patterns, participants must be subjected to a specific level of control and be attached to monitors that measure such rhythms.
This may be invasive for the participant, leading them to sleep in a way that does not represent their ordinary sleep cycle.
This makes investigating ultradian rhythms, such as the sleep cycle, extremely difficult as their lack of ecological validity could lead to false conclusions being drawn.

52. Randy Gardner flexibility of ultradian rhythms.
Randy Gardener remained awake for 264 hours.
experienced numerous problems such as blurred vision and disorganised speech, he coped rather well with the massive sleep loss.
After this experience, Randy slept for just 15 hours and over several nights he recovered only 25% of his lost sleep.
Recovered 70% of Stage 4 sleep, 50% of his REM sleep, and very little of the other stages.
These results highlight the large degree of flexibility in terms of the different stages within the sleep cycle and the variable nature of this ultradian rhythm.