2ConnectWhat questions do you think might come up on what we have studied so far?
3Objectives Today you will So that you can Consider types of exam questionsConsider material you could use to answer these questionsConsider requirements of these questionsSo that you canPlan and produce answers to cover the possible exam questions at least to your target grade standard
4June 12 Outline one or more examples of ultradian rhythms. (4 marks) (This should be about a 100 word answer – no AO2 needed)
5January 11Discuss the role of endogenous pacemakers in the control of one or more biological rhythms. (9 marks marks)(This is just like the newer 24 mark essays. It should be around 200 words of AO1 – and 8 MRI points including at least 1 IDA)
6What else could you get?Outline one or more examples of infradian/circadian rhythms (4 marks)Describe and evaluate research on circadian rhythms (8+16 marks)Describe and evaluate research on infradian and ultradian rhythms (8+16 marks)This question could be split into two lots of (4+8 marks)
7The importance of IDAIf you look at the mark scheme for this unit, you will see that without using IDA at least once in your essays (12 or 24 markers) you cannot reach the top band for AO2.This means that you would be losing at least 4 marks (This could be a whole grade!)But what could you include?
8A2 Psychology: IDA Superheroes ISSUES The Animal AceMaster EthnocentricPassionate that theories are prone to culture bias, The Master of Ethnocentrism would die to prove that theories which are Ethnocentric cannot be applied to all cultures.Questioning the usefulness of animal research. Can animal behaviour be applied to humans?Kitty says no!Gender Bias BeautyThe Ethics KidIronically, the Gender Bias Beauty wants equal application of theories to both Genders. Her pet hate is when theories or studies can only be generalised to one gender or only explain behaviour in just men or just women.Can a theory or study be criticised on the grounds of ethics? Is it unethical? The Ethics Kid is here to find out!
9A2 Psychology: IDA Superheroes DEBATES Nature-ManDoctor DeterminismDoctor Determinism knows that all behaviour is determined by forces beyond human control.Fighting for all things natural. I believe that all behaviour is pre-determined by biological factors: hormones, genes & evolution.Super-Nurture-al.Determined to prove that behaviour is learned and influenced by social forces. I hunt down Nature-Man for the ultimate of battles: The Nature-Nurture Face Off.Free Will-i-amFighting against the evil threat of Determinism, Free Will-i-am believes that we have the power to control our own behaviour. It’s all about the choiceFlying through the skies on a mission to show that psychologists reduce complex behaviour down to over-simplified factors. He believes that behaviour should be looked at holistically.The Reductionist-er!
10A2 Psychology: IDA Superheroes APPROACHES Pavlov’s Power PuppyThe Freud-sterIn the name of Behaviourism, Pavlov’s Power Puppy is here to show that all behaviour can be learned. Just ring that bell and I’ll be there ready to help!In the name of the Psychodynamic approach…Motivated by his unconscious sexual desire, The Freud-ster wants to prove that our behaviour really is only the tip of the iceberg!Tommy TestosteroneDarwin’s DoubleIn the name of Biology, Tommy Testosterone fights to prove that behaviour is underpinned by biological factors: brain structure, neurochemicals and genetics.In the name of Evolution, this Double Act are here to show that humans really did evolve from Apes! It’s all about the genes!The Memory MarvelIn the name of Cognitive Psychology, the Memory Marvel just goes to show that behaviour can be underpinned by cognitive processes. It’s all in the thinking!
11What do you need to be able to do? Write a description of circadian rhythms in about 100 words (4 marks) and 200 words (8 marks)Identify 8 criticisms of this including one IDA topic (MRI – around 50 words each)Write a description of ultradian and infradian rhythms in about 100 words eachIdentify 4 criticisms of each of these including IDA (MRI)
12Circadian Rhythms AO1 AO2 IDA Sleep-wake CycleCircadian = 24 hoursCycle persists despite isolation from lightParticpants not isolated from light in early researchDemonstrated by Siffre and Aschoff & WeverExternal cues important too (Folkard at al)Cycle length varies in individualsBiological approach – suggests bodily rhythms can be explained by biological factorsDeterministic – ignores the element of choice/free will humans have over their behaviourCore body temperatureLowest at 04.30; highest at 18.00Post-lunch dip, even without foodLinked to cognitive abilities (Folkard et al)Evidence that change is caused by temp (Giesbrecht at al)Other research suggests link is spuriousHormonesCortisol lowest at midnightMelatonin and growth hormone highest at midnight.
13Ultradian and Infradian Rhythms AO1AO2IDAUltradianLess than one daySleep stages = 1st 4 – NREM, 5th – REMBRAC = 90 mins within 24 hour rhythmREM does not equal dreamingBRAC important because it ensures biological processes work in unisonDeterminist (e.g. PM) but can change through willpower (Born et al)Real-world application - phototherapyInfradianFemale menstrual cycle regulates ovulationMale shave 20 day cycle of body temp and alertnessSAD caused by melatonin during winter monthsMenstrual cycle also subject to exogenous cuesSome women suffer PMSSAD could also be consequence of disrupted circadian rhythms
14Preparation – working together In our next lesson, you will be writing two essays.Describe and Evaluate research on circadian rhythms (8+16)Describe and evaluate research on ultradian and infradian rhythms. (8+16)
18Connect What might influence our natural rhythms? Make a list of as many things you can think of and try to categorise them into internal (endogenous) and external (exogenous)
19Objectives Today you will So that you can Learn about endogenous pacemakersLearn about exogenous zeitgebersConsider the implications of research done in this areaSo that you canDescribe the role of endogenous pacemakers in biological rhythmsDescribe the role of exogenous zeitgebers in biological rhythmsEvaluate the role of Eps/Ez’s in biological rhythms
20Where is the body clock?Light travels from retina (back of the eye) along the optic nerve, and is picked up by the SCN
21The ticking of the biological clock The basis of circadian rhythm lies in interactions between certain proteins creating the ‘tick’ of the biological clockIt is an ingenious negative feedback loopDarlington et al (1998) first discovered it in fruit flies but actual proteins vary from species to speciesThe protein mechanism is present in SCN (central oscillator) and other cells throughout the body (peripheral oscillators)This explains why different functions have different rhythms
22Body clock negative feedback loop In the morning two proteins bindAs CLK and BMAL1 decrease, production of PER and CRY decreases alsoCLK + BMAL1CRYPERPER + CRYFirst two decreaseThis makes second two decrease alsoThis stimulates production two new proteins24 hour periodCLOCK and BMAL1 begin to decreaseThese new proteins deactivate the first two
23Eps: The suprachiasmatic nucleus (SCN) Tiny cluster of cells, in thehypothalamus, just above optic chiasmObtains info about light via optic nerveIf the sun rises earlier than day before, light resets the clockThere is one in each hemisphere, divided into two parts, dorsal and ventral.Ventral is reset much more quickly, dorsal more resistant to being reset as it is less affected by light (Albus et al, 2005)
24Eps: Pineal gland and melatonin SCN sends signals to pineal gland telling it to increase melatonin at nightMelatonin induces sleep by inhibiting brain mechanisms responsible for alertnessIn birds and reptiles this is just below the thin skull bone and so directly affected by light – light inhibts melatonin production.Some lizards have a third ‘eye’ which sticks out of a small opening in the skull and receives info about light
26ActivityRead over and complete the exercises on endogenous pacemakers in your booklet
27Ezs: Resetting the biological clock This process of resetting the biological clock is known as ENTRAINMENT.The opposite of this is FREE-RUNNINGThis is where the biologicalclock runs without anyexogenous cues.
28Ezs: Light Dominant zeitgeber in humans Light can reset the main pacemaker (SCN)It can also reset other oscillators because the protein CRY (chryoptochrome) is light sensitiveThis may explain why Campbell and Murphy (1998) found that if you shine a light on the back of participants knees, it shifts their circadian rhythms
29Ezs: Social cues Until recently it was thought these were the main EZ’s – we eat, go to bed, get up etcat socially determined timesIt seemed our bodily rhythms were entrained by social convention, not internal biology.Today we know light is the dominant EZ, and we also know that all parts of the body produce their own oscillating rhythms.E.G. zeitgebers for heart and liver appear to be reset by eating, so light is not their primary zeitgeber. (Davidson, 2006)
30Ezs: TemperatureCold blooded animals have their circadian rhythms modified by external temperatureBuhr et al (2010)Humans and other warm blooded animals’ body temperature cycle is governed by the circadian clock, and these temperature changes entrain other circadian rhythms.
31ActivityRead over and complete the activities in your booklet on exogenous zeitgebers
32Review Showdown Where is the SCN? What is its function? Describe how the body clock works?What other examples are there of endogenous pacemakers?What three examples of exogenous zeitgebers have you learned?One study that supports the influence of zeitgebersOne study that supports the influence of pacemakersOne IDA issue that can be applied to this topic
33Homework For next week (TUESDAY!) Discuss the role of endogenous pacemakers and exogenous zeitgebers in circadian rhythms (8+16)There are some documents on Moodle to help you with this.
34Endogenous Pacemakers and Exogenous Zeitgebers AO1AO2IDAEndogenous PacemakersSCN – main EPSCN contains protein mechanismPineal gland controls melatonin secretionSCN evidence – ‘mutant’ hamstersDesynchronisation leads to symptoms similar to jet lagEvolutionary approach – SCN lesions in chipmunks (deCoursey et al)Non-human animal studies evaluated in terms of ethics and relevance.Exogenous ZeitgebersLight is dominant zeitgeberSocial cues also importantBiological rhythms can be entrained by temperatureArtifical lighting may also reset biological clockFailure of biological clock leads to sleep-phase disordersBiological clock is really a blend of endogenous and exogenous factorsYou could also use studies from rhythms topics to add to your AO2:You just need to make sure you say why they are relevant!