biopsych Flashcards

1
Q

nervous system parts

A

CNS: brain and spinal cord
Peripheral NS: Autonomic NS and Somatic NS
Autonomic NS: sympathetic NS parasympathetic NS

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2
Q

Nervous system proper definition

A

a specialised network of neutrons with 2 functions
collect process and respond to info in the environment
coordinate the working of different organs/cells in the body

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3
Q

CNS - parts and function

A

Brain and spinal cord
general processing of information, responding to sensory information

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4
Q

peripheral ns - function and parts

A

function is to transmit messages through neurons to and from CNS and from there to glands/muscles
parts: autonomic ns and somatic ns

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5
Q

somatic ns function

A

transmits info from sensory neurons to CNS and transmits info from CNS to muscles to act
controls CONSCIOUS decisions: run/eat
s/c- conscious

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6
Q

autonomic ns function

A

Transmits messages to/from bodily organs through motor neurons
Controls unconscious decisions: breathing, heart
AUTOnomic, AUTOmatic decisions

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7
Q

autonomic parts and those functions

A

autonomic ns is unconscious processes, aka digestion, breathing…
therefore unconscious decisions are either
1: sympathetic NS: fight/flight system (brain is sympathising with body)
2: Parasympathetic NS: when the body is in a calm state.

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8
Q

fight / flight other name and the symptoms of when it is activated

A

increased heart rate; speed up blood flow to vital organs to improve spread of adrenaline ( released by adrenal glands )
faster breathing rate to increase o2 intake to respire more
production of sweat to facilitate temp regulation because youre not working at the optimal temperature
Decreased saliva production ( digestion is not priority)
increase muscles tensions to improve reaction time and speed
pupil dilation to improve vision as more light is taken in

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9
Q

endocrine system function

A

to regulate cell/organ activity and control processes in the body.
hormones are released from glands into bloodstream.

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10
Q

gland definition
hormone definition

A

Gland - organ that secretes hormones
- hormones are long term, and slower acting but have same effects ( in comparison to nervous system )

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11
Q

master gland name and function

A

Pituitary gland - releases hormones that regulate endocrine systems. Basically organises other glands ‘master gland’

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12
Q

(5) Examples of glands and their functions TOPAT

A

Testes - testosterone released for secondary sexual characteristics in teenagers

Ovaries - oestrogen and progesterone

Pituitary gland - releases hormones that regulate endocrine systems. Basically organises other glands ‘master gland’

Adrenal gland - releases adrenaline ( fight/flight )

Thyroid gland - releases thyroxine, affecting cells in heart increasing the heart rate, also metabolism and therefore the growth rate.

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13
Q

process of adrenaline in the body when fight/flight is activated

A

hypothalamus recognises the threat
Sends a message to pituitary gland
Which sends a message to the adrenal gland ( adrenal medulla )
Therefore triggering release of adrenaline into the bloodstream.

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14
Q

NEURONS - what are they, name the parts

A

( cells that make up nerves )
dendrite
axon
myelin sheath
schwann cells
nodes of ranvier

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15
Q

what do dendrites, axons and myelin sheath do

A
  1. Dendrite - carry impulses from neighbouring neurons.
  2. Axon - communicate with next neuron. Protects the axon and speeds up electrical transmission.
  3. Myelin sheath - fatty layer around neuron to speed up communication, helps impulses travel faster. Wraps around axon
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16
Q

what do schwann cells and nodes do

A
  1. Schwann cells - make up the myelin sheath.
  2. Nodes of ranvier - gaps between Schwann cells
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17
Q

ways to differentiate between sensory, relay and motor cell drawings

A

Motor - connected to muscle at bottom
Sensory - centre has cell body
Relay - doesnt have myelin sheath cause its so small that it doesnt need one.

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18
Q

5 steps in the reflex arc

A
  1. stimulus detected in a gland/muscle
  2. signal sent along sensory neuron
  3. passed along relay neurone
  4. then sent to cns and then along motor neuron
  5. back to effector which creates response
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19
Q

synaptic transmission - four steps

A

it is the way neurons communicate with one another

  1. Electrical impulse reaches end of presynaptic neuron
  2. This causes neurotransmitters to be released from tiny sacs in the pre synaptic terminal called synaptic vessicles. ( fuse with pre synaptic neuron)
  3. The neurotransmitters diffuses across the gap, and connects to post synaptic receptors.
  4. Chemical message is converted back to electrical impulse. There is now a new nervous impulse in post synaptic membrane.
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20
Q

what is summation and the two effects that influence it

A

Summation: whether a neuron is able to meet its threshold and fire towards the next neuron.
Excitatory effect - makes the next neuron more likely to fire ( serotonin )
Inhibitory effect - makes the next neuron less likely to fire

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21
Q

BRAIN: PARTS, LOBES AND AREAS IN LOBES

A

cerebellum
brain stem
frontal lobe - Broca’s area (frontal lobe) - responsible for producing speech
Motor area ( back frontal lobe) - movement

parietal lobe - Somatosensory area ( processing sensory info)

occipital lobe - vision area
temporal lobe - Wernickes area ( back of temporal lobe ) - responsible for understanding speech
Auditory area ( temporal lobe) - responsible for hearing

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22
Q

4 ways of examining the brain

A
  1. post mortem exams
    2.fMRI - functional magnetic resonance imaging
  2. EEG
  3. ERP
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23
Q

what are post mortem exams
pros/cons

A

-analysis of brain after they die done usually on people with rare disorders to understand cause of that and in comparison to a healthy brain
PROS
- post mortem analyses have proven basis of most our understanding, making them reliable on some level
Wernicke and Broca used post mortem to identify the language parts
Post mortems allow for development of medical knowledge.
Only way of examination that allows for neurochemical analysis.
CONS
problem of causation, cause and effect. The damage might’ve been done after death instead of causing the death or it could’ve been a result of something else.
You assume when performing post mortems that any irregularities are the casue of abnormal behaviour but this cannot be tested or confirmed.

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24
Q

fMRI: what is it and pros/cons

A

functional magnetic resonance imaging
. When area of a brain is activated, it consumes more oxygen for more respiration, leading to an increased level of blood flow in that area.
It produces a 3d image different to just an x ray
Helps to identify particular areas of brain associated with difference scans

pros
risk free
Doesnt rely on radiation ( PET SCAN: uses the injection of radioactive glucose into the blood )
Non invasive technique, unlike PET
Ethically safe and straightforward procedure with valuable outcomes.
cons
has poor temporal resolution ( how accurate it pinpoints to nearest second)
fmri is expensive
cant be certain of causation
c

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25
EEG: what is it and pros/cons
Electroencephalogram -Measures electrical activity within the brain through electrodes placed on a persons scalp or skull cap Output represents the brainwave patterns that are generated from electrical activity EEGS are used to diagnose disorders with unusual brainwave patterns such as epilepsy or sleep disorders. Show a general state of brain whereas ERPS show something specific ( remove background noise) nearest cluster of neurons pros highest temporal resolution cons
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comparative points for studying the brain
SICSTERS Spatial resolution Invasiveness - how likely people are to take part. ( linking to sample size ) Causation - show what caused the irregularitiy, post mortem is probably the worst one. Temporal resolution - how fast it can identify an image /movement in the brain ( best = ERP and EEG ) Expense - link to how it reduces the sample size. Risk - metal cannot be in fMRI scans, so people with operations or plates or screws. Sample size/ - Static vs Dynamic - post mortem is static, one image. Dynamic would be fMRI/EEG/ERP casue they show movement
27
Hemispheric lateralisation
idea that hemispheres ( sides of brains ) are functionally different left for logic and right was creative
28
contra lateral
left hemisphere controls right side of body and righ hemisphere controls left side of your body.
29
plasticity
the brain changing and adapting as a result of experiences or learning ( very common in childhood) peaks at 15k synaptic connections at age 2-3 but brain gets less plastic with age ( biggest argument against localisation )
30
functional recovery
when an area of the brain is damaged and another area of the brain performs that function in replacement to help recover.
31
synaptic pruning
act of the brain strengthening useful pathways and deleting unuseful ones
32
negative plasticity plus evaluate
when plasticity is maladaptive and has negative behavioural consequences aka decreased dense matter Pros Cons - prolonged drug use causes negative plasticity in the cognitive functioning area ( more white than grey matter ) - phantom limb in amputees is 60-80% common.
33
one example of negative plasticity
phantom limb syndrome - when amputees continue to experience sensations in their lost limb even though its not there, usually very painful and unpleasant because of plasticity filling the role of the amputated limb that is supposed to be there
34
What is localisation in the brain and evidence for it (3)
- idea that different areas of the brain are responsible for different behaviours/processes ( hemispheres/lobes/areas ) Evidence : - BROCA AND WERNICKE: dicovevered brocas and wernickes area BROCA: found people who had damages to frontal lobe had ‘brocas aphasia’, when speech is slow and lacks fluency r PATIENT TAN ) - phineas Gage: what he DID ( motor ) and what he said ( broca ) was affected which evidences localisation - Peterson : used brain scans to identify activity during memory tasks ( lit up in certain areas ) ( wernickes was active in a listening task and brocas for a reading task )
35
Évidence for functional recovery ( case study )
Gabby Giffords: Politician shot in the head point blank range Was in a waking coma Able to walk with control of her left arm and leg, could write with left hand and read and understand and speak . Pros - long term study - qualitative - cannot be usually studied ethically manipulated Con - ungeneralisable - low internal validity cause of researcher bias.
36
Évidence for plasticity x2 NOT FUNCTIONAL RECOVERY
Maguire et al - london taxi drivers - studied them and found that they have more dense matter in the hippocampus than the comparative control group ( area of brain for spatial and navigational skill ) - this is because of the examination the taxi drivers use to have to take. - shows brain adaption and new learning. Draganski et al - med students - brain scan pre and post final exams - post brain exam found grey matter ( denser particles ) than pre Result of learning and studying .
37
Split brain research - what is it - what does it support - evidence
- where the connection between the 2 hemispheres ( corpus callousum ) is severed , because callosum allows two halves to communicate. - support for lateralisation cause its about the brain consisting of 2 halves. - sperry
38
Sperry (1968)
- studied group of epileptic patients who had had their corpus callosums severed to see the extent to how lateralised the two hemispheres are adn if they have significantly different functions. Procedure: designed to engage either the left or right visual field of the participant. Participants would sit in front of a split ( between 2 eyes ) screen with objects behind that could be touched, but not seen. - severed corpus means info taken in by the right cant be aces by left and contra lateral. Ppts shown word/image to LVF. So that it is processed by RIGHT HEMISPHERE. Then shown to opposite side adn asked to carry out one of four tasks: - describe what they see, recognition by touch, composite words, matching faces. -
39
Sperry 1968 conclusions and pros/cons
Strengths: lab study very controlled: reliable, flashed for a millisecond Increased internal validity: standardised, images presented for one millisecond : ensure other eye didnt have time to adjust. Allows for cause and effect conclusions Weaknesses: lack of population validity ( studied on epileptic patients only who have had this surgery ) people with eplilepsy could have more lateralised brains that the general public. Cant be generalised Deterministic Less representative ( 18 people ) Only did it after split brain surgery ( less reliable ) before the surgery couldve been less lateralised Limited application ( cant be generalised to people without split brain and without being a lab setting ) Not reliable: too nature, isn’t considered nurture Psychometrically test people - personality test Fit people into careers more fit to their dominant left/right brain
40
Explain three tasks carried out in Sperrys study
Describe what you see photo in RVF, patient COULD describe cause Language is in Left h. If its in LVF couldn’t describe the object. Recognition by touch although patient couldn’t describe if shown to the LVF, they could select what one it was with left hand (contra lateral ) Composite words shown two diff words one in each VF Asked to write word with left hand and then say it They could write word they saw with left eye (LEFT EYE AND HAND BOTH WITH RH) But they would say the word shows to RVF cause language = left and that controlled by RVF
41
Three biological rhythms and the 2 aspects that affect sleep wake cycle. Differences
Infradian rythyms: takes longer than 24 hours ( eg: menstrual cycle ) Circadian rythyms: complete a full cycle in 24 hours ( eg: sleep wake cycle ) Ultradian rythyms: take less than 24 to complete a cycle ( sleep cycle ) Endogenous pacemakers: internal body clock exogenous zetigebers: external factors (in the sleep wake cycle)
42
Studies that wanted to find what would happen to sleep/wake cycle if we removed exogenous zeitgeber of daylight. Pros/cons
Siffres Cave study: caveman for two months He found: his sleep cycle extended to 25 hours. He concluded humans have an internal free running clock that is on a 25 hour cycle Siffre - n to social structure Knutsson - ( shift workers around 6 am make more mistakes ) negative Boivin - ( increased risk of heart problems, found correlation between shift work and poor health ) n Aschoff and wever -supports Siffers finding Participants lived in a ww11 bunker for four weeks, with no natural sun light. All but one participant developed a sleep/wake cycle of around 24-25 hours n: shows individual differences. Folkard et al - clock 11.45 - 7.45 , 24 hrs > 22 hours shows influence of exogenous zeitgebers are limited and cr cannot be easily overridden. Campbell and Murphy. - p Dr Paul Kelley - school positive importance of CR and endogenous zeitgebers Bonten : meds for heart attacks aligned with CR to make them more effective as heart a are more often in the morning how CR are positive Strengths Weaknesses environmental reductionism Nurture ( aschoff and wever) Nature/nurture Miles et al (1977) - studied man blind from birth he had a sleep/wake cycle of 25 hours even though he had been exposed to normal social cues( like mealtimes) Man retired sedatives to maintain normal sleep/wake cycle Suggests impact of social cues may be overstated,
43
Siffre
Siffres Cave study: AIM: to see how the body’s sleep-wake cycle would act with no light to regulate Procedure: he lived in a cave for 61 days where no natural light could reach him. He kept track of the days based on when we woke up/fell asleep. He found: his sleep cycle extended to 25 hours. He concluded humans have an internal free running clock that is on a 25 hour cycle
44
Aschoff and Wever.
Aschoff and Wever (1976) supports Siffers finding Participants lived in a ww11 bunker for four weeks, with no natural sun light. All but one participant developed a sleep/wake cycle of around 24-25 hours The one odd one of participant went to 29 hours ( shows that there are individual differences )
45
Outline the sleep/wake cycle process
46
Folkard
12 people in a cave for three weeks Sleep-wake cycle according to a clock and regulated bedtime/wake time 11.45 pm > 7.45 am Didnt know that the clock gradually sped up over time so the 24 hour day eventually shortened to 22 hours Nobody could adjust to new regime Suggests even strong exogenous zeitgebers are limited as circadian rhythms and endogenous pacemakers cannot be overridden easily.
47
Campbell and Murphy’s
Campbell and Murphy’s found that light as an exogenous zeitgeber isnt just picked up by eyes but skin cells 15 participants and adjusted sleep/wake cycle up to three hours jsut using light pad on the back of their knees Shows how important light is as an exogenous zeitgeber
48
Dr Paul Kelly
Monkseaton high school Teens circadian rhythms begin 2hrs after average adult Pushed day back by 2 hours to begin at 10 am Results: Academic results went up Illness decreased Atmosphere improved ( nicer )
49
Boivin
Shift workers more likely to make mistakes around 6 am - economic implications - means the CR are disrupted and affects focus rate.
50
Knutsson
. Found relationship between shift work and poor health, an increased risk of developing heart disease. This means that the disruption of CR also has negative health effects
51
Bonten ( POSITIVE OF CR )
Medical treatment: Circadian rythyms have been used to improve medical treatments. Meaning that the intake of medical treatment can be aligned with a circadian rhythms to be more effective. CR control body processes such as heart rate, digestion… Therefore through chronotherapeutics has found how meds can be aligned to your rhythm. Aspirin for eg is best taken last thing before sleep, because it reduces heart attack likeliness, and heart attacks are most common in the early morning ( bonten et al 2015 ) Shows CR help increase effectiveness of drug treatement
52
Miles et al 1977
Miles et al (1977) - studied man blind from birth he had a sleep/wake cycle of 25 hours even though he had been exposed to normal social cues( like mealtimes) Man retired sedatives to maintain normal sleep/wake cycle Suggests impact of social cues may be overstated,
53
What’s an exogenous zeitgebers and eg
External factors Eg: Caffeine intake Light
54
What’s an endogenous pacemaker and eg
Internal body clock: natural time that you sleep/wake up ( in circadian rhythms) SCN ( suprachiasmatic nucleus )
55
Example of Infradian rythym
Menstrual cycle Menstrual cycle is controlled by endogenous factors such as hormones, but other factors such as pheromones can influence the synchronisation of cycles between women.
56
Study related to infradian rythyms
Stern and McClintock (1998) Aim to demonstrate that menstrual cycles will synchronise as a result of female pheromones. Method: 29 women with a history of irregular periods Gathered pheromone samples from nine of the women at different stages of their cycle Applied sample ( armpit sweat ) to upper lips of participants Findings: 68% of participants experienced changes to their cycle bringing them closed to the odour donor Conclusion: female menstrual cycle can be influenced by exogenous zeitgebers of pheromones Three facilitators for the menstrual cycle: pituitary (master) gland ( controlled by hypothalamus ) Ovary Uterus
57
Process of exogenous zeitgebers affecting a specific infradian rythym
Ir = menstruation EZ = pheromones Hairy green people fart loads on parakeets ( o + p ) Process: Pituitary gland: hypothalamus produces hormone (GnRH), stimulating the pituitary gland to produce FSH (that makes the egg mature and prepare for release) LH (causing egg to be released in the ovary) to begin ovary. ( one egg per cycle). Egg takes 5-6 days to reach the uterus, meanwhile hormone oestrogen is helping womb lining regenerate and progesterone increases lining of the womb.
58
Stern adn mcClintock
Stern and McClintock (1998) Aim to demonstrate that menstrual cycles will synchronise as a result of female pheromones. Method: 29 women with a history of irregular periods Gathered pheromone samples from nine of the women at different stages of their cycle Applied sample ( armpit sweat ) to upper lips of participants Findings: 68% of participants experienced changes to their cycle bringing them closed to the odour donor Conclusion: female menstrual cycle can be influenced by exogenous zeitgebers of pheromones Cons EVALUATION: Evolution of the menstrual cycle THEORY: Menstrual synchrony is thought to be an adaptive positive mechanism. Strength because it may suggest group on infants growing up at PMS: classified as a pathological disorder, because they display heightened emotions pre menstruation Issue cause women are being judged against male standards
59
Evolutionary idea of the menstrual cycle
Evolutionary Basis of the Menstrual Cycle synchrony is thought to be an adaptive mechanism. It is argued that if our ancestors synchronised, that would mean that they would likely get pregnant at the same time. strength - as this would produce a group of infants of the same age, allowing for easier communal care, increasing the likelihood of survivability for the infants. Con Schank (2004). He argued that if too many females were cycling together, this would lead to increased competition for high quality males. This would lead to many having to settle with lower quality mates – reducing the fitness of their offspring. Therefore – there is research that suggests that synchronisation of the menstrual cycle has both adaptive and maladaptive purposes.
60
Schank (2004)
Criticised the idea of menstrual evolutonary cycle Schank (2004). He argued that if too many females were cycling together, this would lead to increased competition for high quality males. This would lead to many having to settle with lower quality mates – reducing the fitness of their offspring. Therefore – there is research that suggests that synchronisation of the menstrual cycle has both adaptive and maladaptive purposes.
61
Studies that are evidence for importance of SCN
Decoursey et al : 30 chipmunks SCN dmaged, observed for a month. Conclusions: the disrupted sleep patterns meant lots were killed at night by predators - reduced alertness and vigilance. Ralph et al : bred mutant hamsters that had 20 hr s/w cycle Transplanted SCN if mutant into health Healthy adapted to 20 hour s/w cycle - shows that SCN is very important endogenous pacemakers for circadian rythyms
62
Ralph et al
Ralph et al. (1990) Bred ‘mutant’ hamsters with a 20 hour sleep/wake cycle. Transplanted the SCN of the mutant hamsters into a healthy hamster. The sleep/wake cycle of the healthy hamster adjusted to 20 hours. - shows importance of SCN as endogenous pacemaker for CR
63
Decoursey et al
Destroyed the SCN connections in the brains of 30 chipmunks. Released back into their natural habitat and observed for 30 days. Found that the sleep/wake cycle of the chipmunks had disappeared by the end of the study – many of them were killed by predators as they were awake and moving in times where they should have been asleep (harder to detect). Disrupted sleep patterns lead to reduced alertness and vigilance :
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What is an Ultradian rythym and example
Less than 24 hours Sleep cycle
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Five stages of sleep cycle
Stage 1 and 2: light stages of sleep whilst your falling asleep Easily woken up during this period Stage 3 and 4: deep sleep/ SWS ( slow wave sleep ) Difficult to wake up Brainwaves slow down REM: body is paralysed and eyes rapidly move Brain patters resemble awake brain (where dreams are thought to happen) Hardest one to wake someone up
66
Stage 1&2 of sleep cycle
Stage 1 and 2: light stages of sleep whilst your falling asleep Easily woken up during this period
67
Stage 3 and four of sleep cycle
Stage 3 and 4: deep sleep/ SWS ( slow wave sleep ) Difficult to wake up Brainwaves slow down
68
REM stage of sleep cycle
REM: body is paralysed and eyes rapidly move Brain patters resemble awake brain (where dreams are thought to happen) Hardest one to wake someone up
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Three studies for sleep cycle evidence
Dement and kleitman monitored the sleep patterns of 9 adults using EEG Caffeine and alcohol were strictly controlled as extraneous variables Found REM was highly correlated with with dreaming Those who woke up during REM had an accurate recall of their dreams Replications have similar findings making it reliable Randy Gardner stayed awake for 11 days / 264 hours He then slept for 15 hours and recovered only 25% of his lost sleep. He mainly recovered 70% of stage four and 50% of his REM sleep highlights flexibility in different stages and importance for each individual Tucker et al found differences in terms of duration of each stage especially 3 and 4 They all shared a similar environment 8 nights, so not caused by the environment Therefore must be biological reasons Infants = 50% REM Adults = 50% in stage 2, and 20% in REM
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Dement and Kletiman
Dement and Kleitman monitored the sleep patterns of 9 adults using EEG Caffeine and alcohol were strictly controlled as extraneous variables Found REM was highly correlated with with dreaming Those who woke up during REM had an accurate recall of their dreams Replications have similar findings making it reliable Evidence of different cycles
71
Randy gardener
Randy Gardener stayed awake for 11 days / 264 hours He then slept for 15 hours and recovered only 25% of his lost sleep. He mainly recovered 70% of stage four and 50% of his REM sleep highlights flexibility in different stages and importance for each individual
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Tucker et al
Tucker et al (2007) found differences in terms of duration of each stage (sleep ultradian cycle)especially 3 and 4 They all shared a similar environment 8 nights, so not caused by the environment Therefore must be biological reasons Infants = 50% REM Adults = 50% in stage 2, and 20% in REM
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What is the SCN: endogenous pacemaker in the sleep wake cycle
endogenous pacemaker in the sleep wake cycle Located above the optic chiasm and receives info about the level of light
74
Process of SCN in receiving light/not
once the SCN detects low levels of light from the optic chiasm, it sends a message to the pineal gland. Pineal gland then begins production of melatonin ( a neurotransmitter that makes want to sleep) and then you fall asleep. Starts to be the day again so then Level of light increases the message to the pineal gland stops and you start to wake up.