OxfordAQA International A-level Psychology (9685): 3.3.1 Psychology of sleep – Practice Questions

These are original questions written for Marlbridge, for revision and practice on this content. They are not reproduced past-paper questions, and they do not replicate the exam’s exact structure, question count or mark tariffs – examination boards hold copyright in their own papers. Use these alongside the official past papers from your board or school.

These questions cover section 3.3.1 Psychology of sleep in the OxfordAQA International AS and A-level Psychology (9685) specification, Version 3.1 (International A-level exams May/June 2020 onwards). The specification assesses this content in Section A of Unit 3: Advanced topics and research methods 2, a 1 hour 30 minute written exam of 90 marks, with 30 marks for Psychology of sleep. Because research methods are also assessed in Unit 3, some questions use invented data. All people, places and data below are fictional.

Revise first with the Psychology of sleep study guide and the sleep revision notes. See the 9685 course hub and the 9685 checklist.

Questions

1. Distinguish between circadian, infradian and ultradian rhythms. [3]

2. Explain the roles of an endogenous pacemaker and an exogenous zeitgeber in the sleep/wake cycle. [4]

3. Tariq, a fictional journalist, flies to a city six hours ahead of his home time. For four days he lies awake until the early hours and struggles to concentrate at morning meetings. When he flies home, he feels normal again after two days.

Use your knowledge of biological rhythms to explain Tariq’s experience. [4]

4. A fictional hospital, Harwick General, trialled two rotas for night nurses for eight weeks. Ward A used a backward rotation (nights, then evenings, then days). Ward B used a forward rotation (days, then evenings, then nights).

	Ward A (backward)	Ward B (forward)
Medication errors per 1,000 night shifts	18	12
Mean self-rated sleep quality (out of 10)	4.1	6.2

(a) Calculate the percentage reduction in medication errors on Ward B compared with Ward A. Show your working. [2] (b) Explain these results using your knowledge of biological rhythms. [4] (c) Identify one limitation of how this trial was designed and suggest how it could be improved. [2]

5. Outline two differences between REM sleep and slow-wave sleep. [4]

6. A fictional sleep lab recorded one participant across four sleep cycles.

Cycle	Slow-wave sleep (minutes)	REM sleep (minutes)
1	40	10
2	30	18
3	12	25
4	3	32

(a) Describe what the data show about slow-wave sleep and REM sleep across the night. [2] (b) Calculate the percentage of this participant’s slow-wave sleep that occurred in the first two cycles. Give your answer to one decimal place. [2] (c) The researchers did not use data from the participant’s first night in the lab. Explain why. [2]

7. Briefly outline restoration theory as an explanation for the function of sleep. [4]

8. At a fictional college, Harwick College, two groups of eight students learned 30 word pairs. The sleep group learned at 9 pm and was tested at 9 am after a night’s sleep. The wake group learned at 9 am and was tested at 9 pm the same day. The number of word pairs recalled is shown below.

Group	Scores
Sleep	22, 25, 19, 24, 23, 21, 26, 20
Wake	17, 20, 15, 19, 18, 16, 21, 14

(a) Write a directional hypothesis for this study. [2] (b) Calculate the mean score for each group. [2] (c) Use memory consolidation theory to explain the difference between the groups. [3] (d) Identify one confounding variable in this design and explain how it could be controlled. [3]

9. Evaluate evolutionary explanations of the function of sleep. [8]

10. Daniyal, a fictional 34-year-old accountant, has found it hard to fall asleep for over a year. He calls himself “a worrier”, checks his work many times before sending it, and lies in bed replaying the day’s conversations. His mother and older brother also have long-term sleep problems.

Explain how personality factors and genetics might contribute to Daniyal’s insomnia. [6]

11. Outline two symptoms of narcolepsy and explain one biological explanation for the disorder. [6]

12. Discuss the effects of shift work and jet lag on the sleep/wake cycle. Refer to endogenous pacemakers and exogenous zeitgebers in your answer. [16]

Answers

1. Circadian rhythms last about 24 hours, such as the sleep/wake cycle [1]. Infradian rhythms last longer than a day, such as the menstrual cycle [1]. Ultradian rhythms repeat more than once in 24 hours, such as the 90-minute cycle of sleep stages [1]. [3] Examiner insight: each mark needs the time span, so an example alone, with no definition, will not score.

2. An endogenous pacemaker is an internal biological clock, mainly the SCN in the hypothalamus [1]. It keeps the sleep/wake cycle running on roughly 24 hours even without outside cues [1]. An exogenous zeitgeber is an external cue, mainly light [1]. Light detected by the retina resets the SCN each day, which adjusts melatonin release from the pineal gland so the cycle stays in step with day and night [1]. [4] Examiner insight: the second mark for each term comes from saying what it does to the sleep/wake cycle, not from naming a brain area.

3. Flying east, Tariq’s local day starts six hours before his body clock expects it [1]. He must phase advance, so at local bedtime his SCN has not yet triggered melatonin release, which explains why he lies awake [1]. The free-running human rhythm is slightly longer than 24 hours, so moving the clock earlier is harder and takes longer [1]. Flying home west is a phase delay, which fits the clock’s natural drift, so he adjusts in two days instead of four [1]. [4] Examiner insight: use the scenario’s details (six hours, four days versus two days); a general account of jet lag caps your marks.

4. (a) 18 − 12 = 6 fewer errors [1]; 6 ÷ 18 × 100 = 33.3% reduction [1]. [2] (b) Forward rotation asks the body to phase delay [1], which is easier because the free-running rhythm is slightly longer than 24 hours [1]. The SCN therefore re-entrains more fully, which fits the higher sleep quality on Ward B (6.2 against 4.1) [1]. Better-adjusted nurses are less sleepy during night shifts, so they make fewer errors [1]. [4] (c) Nurses were not randomly allocated, so differences between the wards, such as workload, could explain the results [1]. Randomly allocate nurses to rotas, or have each ward use both rotas in a counterbalanced order [1]. [2] Examiner insight: in (b), quote at least one figure from the table, because data questions reward use of the data.

5. REM sleep has a fast, desynchronised EEG similar to waking [1], while slow-wave sleep shows slow, high-amplitude delta waves [1]. In REM the eyes move rapidly and the body’s muscles are almost paralysed, with vivid dreaming [1], while in slow-wave sleep the person is very hard to wake and growth hormone is released [1]. [4] Examiner insight: a “difference” needs both sides stated; describing only REM earns half the marks at most.

6. (a) Slow-wave sleep falls across the night, from 40 minutes in cycle 1 to 3 minutes in cycle 4 [1]. REM rises, from 10 minutes to 32 minutes [1]. [2] (b) SWS in cycles 1 and 2 = 40 + 30 = 70; total SWS = 85 [1]; 70 ÷ 85 × 100 = 82.4% [1]. [2] (c) On the first night, the unfamiliar lab and the electrodes often disturb sleep [1], so the record would not show the participant’s typical sleep pattern and would reduce validity [1]. [2] Examiner insight: in (a), a trend statement needs the direction and figures from the start and end of the night.

7. Oswald proposed that sleep restores the body and brain after waking activity [1]. Slow-wave sleep restores the body, as growth hormone is released and tissue repair takes place [1]. REM sleep restores the brain, which may explain why infants, whose brains are developing quickly, have a high proportion of REM [1]. Horne distinguished core sleep (SWS and some REM), which is needed, from optional sleep [1]. [4] Examiner insight: name which type of sleep restores what; “sleep repairs us” earns little.

8. (a) “Students who sleep between learning and testing will recall more of the 30 word pairs than students who stay awake for the same 12 hours.” The hypothesis states a clear direction (more) [1] and operationalises both the IV (sleep or wake) and the DV (word pairs recalled out of 30) [1]. [2] (b) Sleep group: 180 ÷ 8 = 22.5 [1]. Wake group: 140 ÷ 8 = 17.5 [1]. [2] (c) The sleep group recalled 5 more word pairs on average [1]. During slow-wave sleep, new memories held in the hippocampus are thought to be replayed and transferred to the cortex, which strengthens them [1]. Word pairs are declarative memories, and Plihal and Born (1997) linked SWS-rich sleep to better recall of this type of material [1]. [3] (d) Time of day is a confounding variable, because the wake group was tested at 9 pm when tired [1]. This means lower scores could reflect tiredness at testing, not lack of sleep [1]. Add control groups who learn and are tested at the same times of day, for example learning at 9 pm and testing at 9 pm the next day after sleep [1]. [3] Examiner insight: in (d), the explanation mark comes from saying how the variable could produce the result, not just naming it.

9. The real exam marks extended answers using levels of response, not point by point. These are indicative creditworthy points.

Energy conservation theory argues that sleep lowers metabolism, saving energy when an animal cannot usefully feed [1]. Zepelin and Rechtschaffen (1974) found smaller animals with faster metabolic rates tend to sleep more [1], which supports the idea that sleep saves energy [1]. However, many species do not fit the pattern, which weakens it as a general explanation [1].

Meddis (1975) argued that sleep keeps an animal still and hidden when it cannot forage [1]. Allison and Cicchetti (1976) found species in more danger from predators had less REM sleep, consistent with prey needing to stay alert [1].

But sleep makes animals unresponsive, which is risky, and bottlenose dolphins sleep with one brain half at a time instead of going without sleep, suggesting sleep is needed in itself [1]. Evolutionary accounts are hard to falsify and may explain when animals sleep, not why sleep is required at all, so restoration and memory consolidation explanations are still needed [1]. [8] Examiner insight: top-band answers use evidence to judge the theory, then reach a reasoned conclusion, rather than listing studies.

10. Daniyal calls himself “a worrier”, which suggests high neuroticism or anxiety-proneness, a personality factor linked with insomnia [1]. Checking his work many times suggests perfectionism, another trait linked with poor sleep [1]. Replaying conversations in bed is rumination, which raises mental and physical arousal (hyperarousal) at bedtime and delays sleep [1]. His mother and brother also have sleep problems, suggesting a family pattern [1]. Twin and genome-wide studies suggest a moderate genetic contribution through many variants of small effect, which could predispose him [1]. However, his family also shares habits and environment, so a diathesis-stress view, with genes and personality predisposing him and stress triggering the problem, fits best [1]. [6] Examiner insight: each point must link a named factor to a detail of Daniyal’s case to earn the application marks.

11. Excessive daytime sleepiness, with sudden sleep episodes [1]. Cataplexy: a sudden loss of muscle tone, often triggered by strong emotion [1]. Hypocretin (orexin) is a neurotransmitter from the hypothalamus that stabilises wakefulness [1]. In narcolepsy with cataplexy, most hypocretin-producing neurons are lost, so features of REM sleep, such as muscle paralysis, intrude into waking [1]. Lin et al. (1999) found narcolepsy in dogs was caused by a mutation in a hypocretin receptor gene [1]. A link with the immune system gene HLA-DQB1*06:02 suggests the neurons may be destroyed by an autoimmune process [1]. [6] Examiner insight: keep symptoms and explanation separate; symptom detail cannot earn the explanation marks.

12. The real exam marks extended answers using levels of response, not point by point. These are indicative creditworthy points.

Knowledge. The SCN is the main endogenous pacemaker and is entrained daily by light, the main exogenous zeitgeber [1]. Shift work and jet lag cause desynchronisation, as the clock is out of step with outside cues [1]. Night workers must sleep in daylight when melatonin is low, so their sleep is shorter and lighter [1]. Alertness is lowest in the early hours, so errors are more likely on night shifts [1]. Flying east needs a phase advance, which is harder [1]. Flying west needs a phase delay, which is easier because the free-running rhythm is slightly longer than 24 hours [1].

Evaluation. Czeisler et al. (1982) found forward, slower shift rotation improved workers’ schedule satisfaction, health ratings and productivity [1], giving the research practical value for designing rotas [1]. Recht et al. (1995) found baseball teams performed worse after flying east than west, supporting the phase-advance account [1]. However, this was correlational, and travel fatigue and cabin conditions are confounding variables [1]. Health problems linked to shift work are also correlational, and diet and family disruption may contribute [1]. People differ in how quickly they adjust, so effects are not universal [1]. Siffre’s cave study supports a free-running clock slightly over 24 hours, which explains the east/west difference [1], but he was a single case [1]. Because light is the main zeitgeber, controlling light exposure is a logical way to reduce the effects, which supports the theory’s practical use [1]. Overall, the effects are best explained by the interaction between pacemaker and zeitgebers; blaming rhythms alone is reductionist [1]. [16] Examiner insight: an answer that only describes the effects stays in the lower bands; each piece of evidence needs a comment on what it shows and how strong it is.

Where marks are usually lost

• Using a general jet lag account when the question gives a scenario with directions and timings.
• Saying west-bound travel or backward shift rotation is easier.
• Mixing up the SCN (pacemaker), light (zeitgeber) and melatonin (hormone).
• Describing only one side when the question asks for differences.
• Forgetting to show working in calculations, or rounding too early.
• Naming a confounding variable without saying how it could explain the result.
• Treating correlational evidence on personality, shift work or jet lag as proof of cause.
• Describing narcolepsy symptoms at length and giving no biological explanation.
• Ending extended answers without a judgement.

Next steps

• Check gaps with the Psychology of sleep revision notes and the 9685 exam preparation guide.
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Official syllabus

OxfordAQA International AS and A-level Psychology (9685) specification, Version 3.1 (International A-level exams May/June 2020 onwards), section 3.3.1 Psychology of sleep; Unit 3 details in section 2.3.