dreams

REM sleep definition

part of sleep cycle with rapid eye movements caused by eyes moving alot behind eyelids when dreaming occurs

NREM sleep definition

rapid eye movement doesnt occur during sleep

sensory blockade definition

sensory information is blocked during sleep

movement inhibition definition

movement is prevented during REM sleep

how many stages of sleep are there

4

what type of brain waves are present in stage 1 of sleep cycle?

theta waves

what type of brain waves are present in stage 2 of sleep cycle?

theta waves and spindles

spindles definition

bursts of activity

what type of brain waves are present in stage 3 of sleep cycle?

slow delta waves (<50% of time)

what type of brain waves are present in stage 4 of sleep cycle?

slow delta waves (>50% of time)

what happens in stage 1 of sleep cycle

light sleep - easily woken up

muscles are less active

slow eye movements

twitching occasionally

what happens in stage 2 of sleep cycle

slower brain waves

no eye movement

bursts of brain activity

body temperature drops

heartrate drops

what happens in stage 3 of sleep cycle

slower and faster waves occur

stage between light and deep sleep

what happens in stage 4 of sleep cycle

deep sleep

sleepwalking

no eye movement

what happens during REM sleep

vivid dreams

paralyzed muscles

high mixed wave activity

sensory blockade

how is movement inhibition caused

signals in the pons shut up neurons in the spinal cord preventing movement

how long can a cycle of sleep occur

90 minutes

what happens when the cycle progresses

REM sleep lasts longer

less deep sleep

benefits of REM sleep

stimulates cerebral cortex regions associated with learning

develops brain especially during infancy

increases protein

endogenous definition

internal cues from inside us that affect our biological clock

hormones definition

chemical messengers taking messages through the bloodstream

melatonin definition

a hormone involved in setting a circadian rhythm including sleep-wake cycle and blood pressure

pineal gland definition

a small gland that produces a hormone which is secreted into the bloodstream

exogenous definition

external cues from environment that affect our biological clock

zeitgebers definition

external cues that synchronize our body clocks

eg to the 24 hour clock

what controls our circadian rhythm

suprachiasmatic nucleus

scn

what is the scn set by

triggers

eg light, time cues

when does body temperature rise

end of sleep

when does body temperature fall

ready for sleep

what can affect our sleep-wake cycle

jet lag

shift work

ultradian rhythm definition

rhythms that occur in a period that is less than 24 hours

what are ultradian bodily rhythms

heart rate

blood circulation

appetite

what are some internal influences of sleep

hormones

eg when stressed, ACTH hormone releases cortisol, causes alertness and affects sleep

insomniacs have more ACTH than normal amount

strengths of internal influences of sleep evaluation

evidence from hamsters

• removed scn, their bodily rhythms stopped

evidence from blind people

• a blind mans circadian rhythm was closer to 25 hours, meaning that effects are internal

weaknesses of internal influences of sleep evaluation

generalizability

• most research is done on animals, cant generalize to humans

• there are different kinds of blind

primary sleep disorders definition

the disorder is the problem

eg insomnia

secondary sleep disorder definition

sleep problems are the symptoms of another disorder

eg depression

insomnia definition

problems with sleeping at night that cause difficulties during the day

types of insomnia

acute

chronic

how common is insomnia

1/3 people

symptoms of insomnia

difficulty falling asleep

waking up during night

not feeling refreshed on waking

what causes insomnia

lifestyles

health conditions

medication, food and drink

• such as smoking, on antidepressants, alcohol

narcolepsy definition

inability to control sleeping and waking, so experiences involuntary daytime sleeping

how common is narcolepsy

1/2000

cataplexy definition

loss of power muscle and tone triggered by an onset of strong emotions

symptoms of narcolepsy

extreme sleepiness

hallucinations and vivid dreams

sleep paralysis

what causes narcolepsy

lack of brain chemical orexin, used to keep us awake

genetic influence

• variation in chromosome 6

stress and evolution

what is freuds iceberg theory

5% conscious mind

95% unconscious mind

• wishes/desires

according to freud, dreams =

symbols

id definition

part of freuds personality theory that is demanding

superego definition

part of freuds personality theory that is sensible / the conscious

ego definition

part of freuds personality theory that is the reasoning

balances id and superego

dreamwork definition

transformation of unconscious thoughts into dream content

latent content definition

meanings behind dream symbolism

what are the 3 mechanisms of dreamwork to protect recessed thoughts

condensation

displacement

secondary elaboration / revision

condensation definition

many latent ideas appear as one manifest idea

displacement definition

in dreams, something unimportant seems to be important, shifting attention away from the important thing

secondary elaboration / revision definition

using muddled ideas from dreamwork to build the whole story

mind will add bits to make it make sense

strengths of freuds theory of dreaming

qualitative data makes it have higher validity as he asked patients

evidence as Guenole et al found that dreams garded sleep

weaknesses of freuds theory of dreaming

dreams cannot be tested

unscientific - dreams cannot be measured

not generalizable

what is the activation-synthesis theory (Hobson and McCarley)

brainstem sends random signals to cortex

cortex tries to make sense of it

strengths of the activation-synthesis theory

model is still being investigated and evolved

evidence - found activity in the pons in cats

weaknesses of the activation-synthesis theory

were not cats

theory is not in its original form, not reliable

aim of the siffre study

how people would get on traveling in space where there are no zeitgeibers

wanted to find his natural body clock

procedure of the siffre study

spent 6 months without zeitgeibers in midnight cave, usa

did experiments on himself like blood pressure and memory

shooting practice tests for accuracy

wrote in journal

results of the siffre study during the experiment

became desperate for companionship, became friends with mouse, rat, cockroach

record player broke and books, clothes, games got damp

he got suicidal

STM and LTM got affected

sleep-wake cycle had variations (24-52 hours)

results of the siffre study after the experiment

eyesight and cough was worse

had psychological problems

conclusion of the siffre study

natural circadian rhythm had variations without zeitgeibers

being alone leads to suicidal thoughts, astronauts need companionship when they fly

strengths of the siffre study

so much of both quantitative and qualitative data was recorded

• his thoughts, blood pressure, memory tests, physical tests

done over a large period of time - longitudinal

weaknesses of the siffre study

he used lights, not completely in dark

not generalizable to wider public because HE only got tested

aim of little hans study

to cure a childs phobia of horces

build evidence for freuds therogy of psychosexual stages

procedure of little hans study

results of little hans study (horses)

he was scared of horses falling down and dying as he saw a horse die in the street

he did not like horses with blackness around the mouth

freud: blackness = dads moustache, horse = dad

so hans had an unconscious fear of dad not horses

dad was rival for mom

phobia improved through imagination and role play

less anxiety

results of little hans study (mom )

had a dream about mom leaving

freud connected it to his theory

results of little hans study (giraffe)

there was big giraffe and crumpled giraffe

hans took crumpled giraffe away

freud said big giraffe was a symbol of a penis

hans liked getting into bed with his parents

dad didnt

= oedipus theory

conclusion of little hans study

children have hidden feelings they dont understand

supported his theory regarding oedipus thoery

strengths of little hans study

detailed information - qualitative

ecological validity - not in lab

weaknesses of little hans study

biased source - parents loved freud

not generalizable - one boy with obscure phobia