Unit 9: Sleep and Dreaming Flashcards
How many cycles are in a typical night of sleep?
5 cycles
How long does each cycle last in your sleep?
90 minutes
What is REM sleep?
rapid eye movements
part of the sleep cycle with rapid eye movements caused by eyes moving a lot behind the eyelids when dreaming occurs.
Describe stage 1 of the sleep cycle
light sleep
- can be easily woken up
- muscles less active
- eye movements slow
- sudden twitching
- alpha and theta brainwaves
Describe stage 2 of the sleep cycle
late night stage
- brainwaves slower
- mainly theta waves
- eye movements stop
- bursts of brain activity (spindles)
- temperature and heart rate drop
Describe stage 3 of the sleep cycle
deep sleep
- slow delta brainwaves
- some faster waves
- between light and deep sleep
this is when nightmares and sleep walking occur
Describe stage 4 of the sleep cycle
deep sleep
- almost all slow delta waves
- hard to wake you up
- no eye movements
- woken very disoriented
What are some features that occur during REM sleep?
flickering eyelids, irregular breathing, muscle paralysis, heart rate + blood pressure rise
Describe the stages of the sleep cycle
first you go through stages 1-4, this is known as the NREM sleep
after that you have REM sleep which is where you dream
How many hours on average do people dream per night?
2 hours
What is sensory blockade?
when in REM sleep all incoming sensory information is blocked
What is movement inhibition?
when in REM sleep movement is prevented as muscles are paralysed, The pons send a signal to the spinal chord to shut off neurons which prevents us from moving.
How many hours of sleep do adults need?
7-8 hours
How many hours of sleep do teenagers need?
9 hours
What is sleep deprivation?
not having enough sleep, which can affect physical functioning and brain functioning
How much sleep on average is REM sleep in adults?
20%
How much sleep on average is REM sleep for children?
80%
Why do infants have more REM sleep than adults?
because REM sleep stimulates learning and infants are building 700-1000 neural connections every second, as they create schemas.
During an average nights sleep, which stage is the longest dreaming period?
5th cycle
In which stage is it the hardest to wakeup?
stage 3-4 as theres sensory blockade and movement inhibition
What are circadian rhythms?
biological internal (human) rhythms that have a daily (24 hour) cycle
Describe the changes in body temperature during a nights rest
the body temperature is in tune with he sleep wake cycle. It rises when you get ready to sleep and also towards the end of sleep.
What is the SCN?
superchiasmatic nuclei
found in the middle of the brain controls circadian rhythms and set by exogenous triggers (eg. light)
What is the sleep-wake cycle?
a circadian/daily rhythm generally triggered by the day and night cycle (light + time cues)
What are ultradian rhythms?
rhythms that occur in a period of less than 24 hours, such as the sleep cycle (with the 5 90 minute cycles)
these rhythms influence our circadian rhythms + sleep-wake cycle
What is endogenous?
internal pacemakers, our biological clock. these are internal factors that control our circadian rhythms.
What are hormones?
chemical messengers taking messages through the bloodstream.
What is melatonin?
a hormone involved in setting circadian rhythms in response to darkness, produced in the pineal gland
What hormone can be used to treat insomnia/jetlag?
melatonin
What happens to our hormones when we fall asleep?
sleep resets our hormones
What is adrenaline?
a hormone involved in the fight or flight response that makes us alert.
Why is adrenaline rush before you sleep bad?
it keep you alert making it harder for you to fall asleep
What is SAD?
seasonal affective disorder, it is when the body secretes too much melatonin in the dark even though it is still early. this can cause you to feel sad, or be depressed in colder seasons.
What is exogenous?
external cues in the environment that5 affect our circadian rhythms
What are zeitgebers?
external cues that synchronise our biological rhythms.
these tell you the time and affect your biological clock, instead of internal rhythms like hormones.
What are some examples of zeitgebers?
24 hour clock, day-night cycle, 12 month cycle of seasons
What are some examples of exogenous factors?
light, stress, medication, caffeine
What are the types of sleep disorders?
primary sleep disorders and secondary sleep disorders
What are primary sleep disorders?
when the disorder is the problem which directly disrupts sleep
What are secondary sleep disorders?
the side effects of a disorder affects sleep, eg. depression
What is insomnia?
problems with sleeping at night that cause difficulties during the day
What are the two types of insomnia?
acute insomnia and chronic insomnia
What is acute insomnia?
brief period of problems with sleep
What is chronic insomnia?
when difficulty in sleep occurs three or more nights a week, lasting at least 3 months
What are the symptoms of insomnia?
difficulty with falling asleep, waking up during the night, frequently lying awake during the night, not feeling refreshed after waking, finding it hard to fall asleep when during the day you were tired, feeling irritable and unable to concentrate
What are some causes of insomnia?
flying frequently causing frequent jetlag which disrupts circadian rhythms
depression and heart problems may contribute to insomnia
What is narcolepsy?
a brain disorder where there is an inability to control sleeping and waking, therefore experiencing involuntary daytime sleeping
How frequent is it for people to have insomnia compared to narcolepsy?
1 in 3 people have insomnia
1 in 2000 people have narcolepsy
What are the symptoms of narcolepsy?
- uncontrollable EDS
- hallucinations and vivid - dreams (experiencing untrue things)
- cataplexy attacks (often during sleep paralysis)
- sleep paralysis
- abnormal REM sleep
What is EDS?
excessive daytime sleepiness, occurs in narcolepsy
What are cataplexy attacks?
loss of muscle power and tone, triggered by an onset of strong emotions such as laughter, so random occurrence of muscle paralysis
How does someone develop narcolepsy?
cells that are supposed to produce hypocretin are damaged/missing, resulting in EDS and symptoms of narcolepsy.
10% of people with narcolepsy have family with it too, which may relate to inheritance of the hypothalamus issue (HLA complex, where people inherit variations in chromosome 6.
Wayne Barker 1948 found that stress/trauma may also lead to narcolepsy
How might cataplexy attacks be helpful?
a survival value/technique to stay still during muscle paralysis
What is the unconcious mind?
an inaccesible part of the mind that affects behaviour and feelings
What are stages in your unconscious mind?
conscious mind, preconscious mind, unconscious mind
What is the conscious mind?
mental activity we are all aware about, our thoughts and perceptions
What is the preconscious mind?
mental activity we could be aware of if we tried, memories and stored knowledge
What is the unconscious mind like?
no control over your mental activity and you aren’t aware of it at all either. these are fears, unacceptable desires, immoral urges, selfish needs and traumatic experiences
What is the importance of the unconscious mind?
our dreams involve symbols that have meanings which can be analysed by a psychoanalyst. we repress our thoughts and feelings if their inappropriate and this repression can call mental health problems, so it’s important to reveal these to release stress.
What percent of our thinking is unconscious?
90%, however this cannot be fully proved therefore lacks validity.
What is the Id?
the thought of desires (almost demanding)
it is the part of our mind with our manifest desires
What is the ego?
the reasoning, the balance the demands of the id and superego
What is the superego?
thoughts that you cant have something
against your id
What is the manifest content?
the story the dreamer tells of what happens in the dream, it is subjective as the dreamer might indulge in displacement or secondary elaboration
What is the latent content?
the deeper meaning behind what is said the dream is about
What is dreamwork?
the transformation of unconscious thoughts into dream content, it hides the unconscious thoughts into symbols in your dream so that we can’t uncover them (in order to protect us from immoral/inappropriate desires0
What are the procedures within dreamwork?
condensation, displacement and secondary elaboration
What is condensation?
when multiple ideas appear as one in a dream
What is displacement?
when something unimportant seems important in a dream, shifting attention away from the real ideas
What is secondary elaboration?
using muddled ideas from dreamwork to build a whole story and adding bits to make it make sense
What is psychosexual stages?
freuds theory of stages in children.
What are the psychosexual stages?
oral stage, anal stage, phallic, latent stage, genital stages
What is the phallic stage?
the third stage during which the oedipus complex occurs
At what age are children in the phallic stage?
3-5 years old
What is the oedipus complex?
when young boys have sexual desires for their mother and hates their father as they fear they will be castrated if their father finds out about these unconscious thoughts
What did Hobson and McCarley (1977) find?
they created the activation-synthesis theory of dreaming
What is the activation synthesis model?
a neurobiological theory of dreaming
Explain the activation synthesis model
the brain is active during REM sleep, specifically the pons is active and brainwaves are generated and activity increases. they create a random firing of neurons that pass through the synaptic gap. these brainwaves travel to the areas in the cerebral cortex where our brain tries to interpret that information by synthesising it. however it is just nonsense so our brain refers to the stored memory to make it make sense.
What is the conclusion of the activation synthesis model?
Hobson and McCarley concluded that dreams have no real meaning or latent content, it is just a random firing of neurons which reveal random thoughts, not any unconscious ones.
What is blocked in REM sleep?
physical movements/movement inhibition and sensory blockade (stimulation + sense information from outside of the body)
What is active during REM sleep?
perception from WITHIN the brain (generated internally) and rapid eye movements
What is modulation?
neuron activation in the brain and memory of consciousness of the information activated
What is the AIM model?
activation
input and output prevention
modulation
What is the background of Siffre’s 1975 study?
in 1962 siffre spent 63 days in a cave in france to see how his body clock reacted to him not having normal time cues. this experiment was sponsored by NASA and repeated until how found the length of the sleep-wake cycle. he wanted to replicate his experiment 10 years later
What was the aim of Siffre’s study?
to see how people would get on travelling through space, as they would be isolated and have no zeitgabers
to find the natural sleep-wake cycle was without exogenous factors and our reliance on zeitgabers
What was the procedure for Siffre’s study?
he went into midnight cave in texas on 14th febuary 1972 and came out in september of the same year. he lived in a large chamber further from the cave. he undertook experiments in the cave.
What were the results of Siffre’s study?
he became depressed towards the end of the study due to his lack of freedom and was desperate for companionship (he trapped a mouse to have a friend)
he started thinking of suicide when his entertainers broke, the result of the dark and loneliness and he came out with bad eyesight and psychological problems
his short term memory was affected
he didn’t get his days and nights correct, his sleep-wake cycles ranged from 18-52 hours and 2 periods where it was 48 hours (which was his hypothesis 36 hours awake and 12 hours asleep)
What were the conclusions of Siffre’s study?
lots of variation in his sleep-wake cycle in the absence of zeitgebers
the body clock might be manageable if irregular
isolation in confined space wasn’t manageable (so astronauts would need companionship)
he concluded time is not something humans can work with without external cues
What was the background of Freud (1909) study?
he initiated talk therapy to help people with psychological issues and phobias
he conducted a case study with little hands for his theory of psychosexual stages (specifically the oedipus complex)
What were the aims of Freud’s (1909) study?
to help the indvidual (little hans)
to build evidence for his theory of how children develop
What was the procedure for Freuds (1909) study?
he gathered information from the reports given by the boy’s parents, and information directly from the boy
at 5, Han’s was scared to leave the house because of his phobia of horses, he used this information to uncover the boys unconscious thoughts in order to cure the phobia by using psychoanalysis
What was Han’s phobia?
he was scared that the horses he saw would collapse on the street, especially if pulling carts. this could be because he witnessed a horses death, but Freud thought the horse was a symbol for Hans’ father and he was scared he would castrate him
What was little Hans’ earlier dream?
at 5 years old he thought his mother was gone
this is the anxiety complex that his father would take her away if he found out about Hans’ inappropriate thoughts,
What was the giraffe dream?
there was a big giraffe (penis) who shouted because little Hans took the crumpled giraffe (mom) away
which is why Hans would get into bed between his parents in the morning, and his father didn’t like it. this was taken as a claim that the boy had sexual desires for his mother.
What were the conclusions of Freuds (1909) study?
he used these dreams as evidence to support his theory that children develop in psychosexual stages, especially for the phallic stage.
Hans wanted to keep his mother to himself and his father away and he believed that the giraffe dream represented the oedipus complex.
