Module 8: Sleep and Dreaming

Question 1

Explain NREM sleep

Answer 1

• Stage 1: light sleep, easily woken, alpha/theta brainwaves, eye movements slow
• Stage 2: late night, brain activity bursts (spindles), body temperature drops, heart rate slows, eye movements stop
• Stage 3: transition between 2 and 4
• Stage 4: deep sleep, slow delta waves, hard to wake, sleepwalking/nightmares in children

Question 2

Explain REM sleep

Answer 2

• Rapid eye movement
• Dreaming - 2hrs per night
• Sensory blockade
• Movement inhibition (spinal cord neurons turned off by pons)
• Heart rate/blood pressure rises

Question 3

Explain the sleep cycle

Answer 3

• Five cycles (1 = 90mins)
• Deep sleep and little REM –> light sleep and long REM (up to an hour)

Question 4

What are the functions and benefits of sleep?

Answer 4

• Deep sleep stops after age ~65
• Sleep needed for learning and survival
• 20% of sleep is REM, 50% for babies
• Dreaming can occur in NREM
• Adults need 7-8hrs, teens need 9hrs

Question 5

Explain circadian rhythms

Answer 5

• Controlled by suprachiasmatic nuclei (SCN) which is set by external triggers
• 24 hour cycle (sleep/wake, body temperature)

Question 6

Explain zeitgebers as an external influence on sleep

Answer 6

• Environmental cues (light/dark cycle, seasons, hunger)
• Entrainment - biological rhythms being matched to external triggers

Question 7

What are the strengths and weaknesses of zeitgebers as an external influence on sleep?

Answer 7

• Strengths: Practical applications (aid shift workers), Mistlberger & Skene (2004) found light a strong influence on sleep
• Weaknesses: Differing findings (Siffre 1975), studies usually unnatural

Question 8

Explain ultradian rhythms

Answer 8

• Less than 24 hours
• Sleep/REM cycle, heart rate, hunger, etc

Question 9

Explain internal influences on sleep

Answer 9

• Biological clock internal, keeps all rhythms synchronised
• Hormones: adrenaline/cortisol affect sleep, sleep resets hormones
• Melatonin signals need to sleep, released by pineal gland (trigger by darkness)
• Melatonin works as medication for insomnia/jet-lag (not shift workers)

Question 10

What are the strengths of internal influences on sleep?

Answer 10

• Evidence from animal studies
• Miles et al (1977) human study on blind person
• Li-You Chan et al. (2015) evidence for melatonin

Question 11

What are the weaknesses of the theory of internal influences on sleep?

Answer 11

• Cannot always generalise animals studies to humans
• Evidence relating to blindness is weak

Question 12

What are the symptoms of insomnia?

Answer 12

• Difficulty falling asleep
• Waking a lot in the night
• Not feeling refreshed waking up
• Feeling stressed/irritable
• Acute/chronic, 1 in 3 people, more common in older people

Question 13

Give explanations for insomnia

Answer 13

• Jet lag/night shifts
• Health conditions (physical/mental)
• Medication, food, drink (hormones affected)

Question 14

What are the symptoms of narcolepsy?

Answer 14

• No control over sleep/wake cycle
• EDS (excessive daytime sleepiness)
• Hallucinations and vivid dreams
• Cataplexy in 70% - loss of muscle power/tone due to onset of strong emotions (e.g laughter)
• Sleep paralysis and abnormal REM
• Affects 1 in 2000 people

Question 15

Give explanations for narcolepsy

Answer 15

• Lack of hypocretin
• May be genetic
• Stress/trauma
• May have evolutionary benefit (play dead)

Question 16

Explain Freud’s theory of dreaming

Answer 16

• We repress unconscious wishes/desires and dreams can uncover them (through dreamwork)
• Know them, they’re released from the subconscious, you no longer take up energy repressing them, no more anxiety

Question 17

Explain dreamwork (of Freud’s theory of dreaming)

Answer 17

• How the mind protects itself by hiding unconscious desires in dreams:
• Condensation - many ideas appear as one
• Displacement - what seems important is not (shifting away focus)
• Secondary elaboration - added details to make sense of story
• Symbolic meanings different for everyone, knowledge of patient needed

Question 18

What are the strengths of Freud’s theory of dreaming?

Answer 18

Qualitative, detailed, focused - strengthens validity

Question 19

What are the weaknesses of Freud’s theory of dreaming?

Answer 19

Cannot be tested/shown as true or false - unscientific

Question 20

Explain Hobson and McCarley’s (1997) Activation-Synthesis theory of dreaming

Answer 20

• Activation: neurons randomly activated –> messages (thoughts) sent in brain - all information internally generated
• Synthesis: brain makes sense of internal info the same way it does with external - this creates dreams

Question 21

What are the strengths of Hobson and McCarley’s (1997) Activation-Synthesis theory of dreaming?

Answer 21

• Evidence: senses blocked so dreams must be internal, pons active during cats’ dreaming
• Model still being used/investigated today

Question 22

What are the weaknesses of Hobson and McCarley’s (1997) Activation-Synthesis theory of dreaming?

Answer 22

• Animal studies not always generalisable
• Dreams often linked to previous days’ events (not entirely random)
• Has been built on/amended (didn’t last on its own merits)

Question 23

What was the background of Freud’s (1909) Little Hans study?

Answer 23

• Psychosexual stages of development
• 3-5yrs old: phallic stage, gendered behaviour through identifying with same-sex parent, oedipus complex

Question 24

What were the aims of Freud’s (1909) Little Hans study?

Answer 24

• Help the individual
• Gather evidence for theory on how children develop (psychosexual stages)

Question 25

What was the procedure of Freud’s (1909) Little Hans study?

Answer 25

• Detailed information from Hans’ parents
• Dreams and phobia of horses (including but not limited to)
• Only some information from Little Hans himself

Question 26

What were the results of Freud’s (1909) Little Hans study?

Answer 26

• Hans saw a horse fall in the street & had a fear of horses (black around mouth): horses = father (moustache), unconscious fear (oedipus complex), rearranged father to ‘grandfather’ role to alleviate anxiety
• Early dream, mother was gone: fear father would take mother away (oedipus complex)
• Dream, big & crumpled giraffe, takes small giraffe and big one shouts at him: mother and father, oedipus complex (Hans denied this)

Question 27

What were the conclusions of Freud’s (1909) Little Hans study?

Answer 27

• Evidence for Oedipus complex (fear of father, wanting to posses mother)
• Fear of horses an example of this

Question 28

What are the strengths of Freud’s (1909) Little Hans study?

Answer 28

• In-depth detailed qualitative analyses
• Carefully documented, reflective account, scientifically carried out

Question 29

What are the weaknesses of Freud’s (1909) Little Hans study?

Answer 29

• Parents followers of Freud’s ideas, so information passed on was biased
• Case studies not generalisable and unsuited for building theories (as Freud was doing)
• Learning explanation for horse phobia - saw a horse fall and die

Question 30

What was the background of Siffre (1973) 6 Months Alone in a Cave?

Answer 30

• Replicate previous 1962 study (also conducted by Michael Siffre, on himself and others - 24hr clock for him, 48hr for others)
• NASA sponsored the study

Question 31

What were the aims of Siffre (1973) 6 Months Alone in a Cave?

Answer 31

• Investigate how astronauts would react to not having zeitgebers to set biological clock
• Find whether ‘natural’ sleep cycle 24hr or 48hr

Question 32

What was the procedure of Siffre (1973) 6 Months Alone in a Cave?

Answer 32

• Spent 14 Feb 1972 - Sep 1972 alone in a cave in Texas
• No indication of date/time, woke up and turned lights on, was tired and turned lights off
• Memory/physical tests taken after waking up

Question 33

What were the results of Siffre (1973) 6 Months Alone in a Cave?

Answer 33

• Became depressed/suicidal, desperate for companionship
• Short term memory negatively affected
• Sleep-wake cycle initially longer than 24hrs, but then ranged from 18-52hrs

Question 34

What are the strengths of Siffre (1973) 6 Months Alone in a Cave?

Answer 34

• Significant quantitative and qualitative data
• Long period - 6 months, ensure no patterns could be found in the sleep-wake cycle

Question 35

What were the conclusions of Siffre (1973) 6 Months Alone in a Cave?

Answer 35

• Body clock manageable, though erratic/variable without zeitgebers
• Companionship required

Question 36

What are the weaknesses of Siffre (1973) 6 Months Alone in a Cave?

Answer 36

• Lights upon waking - external cue
• Case study, not generalisable (to astronauts)