Biopsychology Flashcards
(154 cards)
1
Q
What is the nervous system split up into?
A
- central nervous system
- peripheral nervous system
2
Q
What is the human nervous system?
A
A body wide system of nerve cells that collects and processes information and then directs organs and muscles via electro chemical messages
3
Q
What is the function of the CNS and what 2 parts of the body do they contain?
A
- complex processing
- the brain (all conscious and most unconscious processing)
- the spinal cord (receives and transmits information, also is responsible for some simple reflexes)
4
Q
What is the peripheral nervous system?
A
A body wide network of messenger neurons that transmit information to and from the CNS
Split into the ANS and SNS
5
Q
What is the PNS split into and what are they?
A
- somatic nervous system (controls skeletal muscles and is a voluntary system)
- autonomic nervous system (controls actions of internal organs and glands and is an involuntary system)
6
Q
What does the sympathetic branch (ANS) do?
A
Increases bodily activities and releases noradrenaline in a stress response (fight or flight)
-heart rate increase
-sweat increase
-breathing rate increase
-dilates pupils
-inhibits digestion
7
Q
What does the parasympathetic branch do?
A
Decreases bodily activities and releases acetylcholine. Activates in rest (rest and digest)
-heart rate decrease
-sweat decrease
-breathing rate decrease
-constricts pupils
-stimulates digestion
8
Q
What is the motor cortex responsible for?
A
Responsible for voluntary motor movements
9
Q
Where is the motor cortex found?
A
Found in BOTH frontal lobes of the brain
10
Q
What is the function of the somatic nervous system?
A
Voluntary system controlling skeletal muscles for movement
11
Q
What is the function of the autonomic nervous system?
A
Involuntary system of internal organs and glands
Divided into sympathetic and parasympathetic
12
Q
What is the autonomic nervous system split into?
A
The parasympathetic nervous system / the sympathetic nervous system
13
Q
What is the function of the sympathetic nervous system?
A
Co-ordinates organs when in situations when the individual needs to be aroused / when our muscles need oxygen
Signals to our hearts,lungs and liver when to work harder
14
Q
What is the function of the parasympathetic nervous system?
A
Co-ordinates to our organs when we can relax and conserve energy
Rest + digest
15
Q
What happens to the eye, heart and saliva glands in the SNS
A
Pupil dilates
Heart rate increases
Inhibited saliva production
16
Q
What happens to the eye, heart and saliva glands in the PSNS?
A
Constricts pupil
Heart rate decreases
Stimulated saliva production
17
Q
What are the 6 parts of a neuron?
A
- Cell body / soma
- Nucleus
- Dendrites
- Axon
- Myelin sheeth
- Axon terminal
18
Q
What is the function of the soma?
A
Control centre of the neuron and includes the nucleus
19
Q
What is the function of the nucleus?
A
Contains genetic material of the cell
20
Q
What is the function of the dendrites in a neuron?
A
Dendrites recieve signals from other neurons or from sensory receptor cells. Typically connected to cell body
21
Q
What is the function of the axon in a neuron?
A
Long slender fibre that carries nerve impulses in the form of an electrical impulse, action potential.
22
Q
What is the function of the myelin sheath in the neuron?
A
Insulates axon so impulses travel faster and preserves the signal
23
Q
What is the function of the axon terminal in a neuron?
A
Connects the neuron to other neurons using a process called synaptic transmission
24
Q
What is unique about a relay neuron?
A
A relay neuron has no myelin sheath
25
What is unique about a sensory neuron?
In a sensory neuron the cell body sticks out
26
What is the function of a sensory neuron?
Sensory neurons transmit nerve impulses from sensory receptors to the brain and spinal cord
Impulses begin as sensory receptors and are translated into sensations at the brain which allows for reflex actions
27
What is the function of a motor neuron?
Carry impulses from the CNS to other areas of the body
Releases neurotransmitters which bind to muscle receptors and trigger muscles movement
Muscle relaxation is caused by the inhibition of the motor neuron
28
What is the function of a relay neuron?
Connect sensory and motor neurons allowing for communication
Located in brain and spinal cord
29
What neurons are uni/multipolar?
Unipolar- sensory neurons
Multipolar- motor and relay neurons
30
What was the aim of Sperry and Gazzanigas study?
To investigate the effects of hemispheric deconnection and to show that each hemisphere has different functions
31
What was the method of sperrys split brain study?
Comparing performance of 11 split brain patients, who had undergone surgery for their epilepsy to people with no connection
In lab conditions, participants were asked to fixate on a dot in centre of screen while a word or picture was flashed to the left or right visual field for 1/10 of a second
They would then make responses verbally or using left/right hand without being able to see their hands
32
What were the results of the split brain study?
1. When object was shown to right visual field the patient could easily say what was seen but if object was shown to left visual field they reported nothing was there - although could identify object from a grab bag using their left hand
2. If two words were simultaneously on either side of the visual field the patient would write the word on the left with their left hand and say the word on the right
3. When asked to match a face from a series of faces, picture processed from right hemisphere was consistently selected whereas left hemisphere was consistently igored
33
What are the evaluation points of split brain research? AO3
+ quasi experiment / high control
+ pioneering research
- population validity
- individual differences - lateralisation not fixed
34
How does split brain research have high control? AO3
P: Sperry and Gazzanigas research is a quasi experiment we they were able to take advantage of the naturally occurring variable as the epileptic patients had experienced hemisphere deconnection
E: able to have high control over the experimental environment and so demonstrate the effect that hemisphere disconnection has on brain function
E: since hemisphere deconnection was regarded as the only significant difference between the two groups, the observed difference in performance was seen as having been caused by this deconnection so providing support for the theory of hemispheric lateralisation
L: consequently it can the argued that this study has high internal validity
35
How is Sperrys split brain research pioneering research? AO3
P: this research had a huge impact on our understanding of how different hemispheres of the brain work
E: Sperry and Gazzanigas work into split brain has produced an impressive sizeable body of research that suggests that the left hemisphere of the brain is more analytical and verbal and the right is more adept to spatial tasks and music
E: this is a strength as the research has enabled scientific progress
36
How does Sperry and Gazzanigas split brain research have low population validity? AO3
P: research has low population validity
E: sample consists of only 11 split brain patients which is a small sample size which may not be representative. In addition, participants epilepsy may of caused changes in the brain which are not present in the brains of others - another reason why the sample may be unrepresentative
E: consequently, it can be argued that this study lacks external validity
37
How are individual differences a limitation of Sperrys split brain research? AO3
P: lateralisation appears to change with age and for many types of task
E: patterns in younger individuals tend to switch to bilateral pattern in health older adults. For example, Szaflarski found that language becomes more lateralised in the left hemisphere with increasing age, but after the age of 25 lateralisation decreased with each decade of life. This suggests that older people’s brains recruit both hemisphere to increase their processing power, perhaps to compensate for age related cognitive decline
E: this is a limitation of hemispheric lateralisation theory because these findings suggest that the theory might not be completely correct
38
What does plasticity refer to?
The brains tendency to change or adapt
39
What age did Gopnik find to have the most synaptic connections?
2-3 years old with 15,000 connections
40
What is synaptic pruning?
When neurons that are rarely used die
41
How does the brain constantly adapt to a changing environment?
By developing new pathways and pruning away weak ones
42
What does synaptic pruning enable?
Lifelong plasticity because new neuronal connections are formed in response to new demands on the brain
43
What was Boyke et als plasticity study?
60 year olds taught new skill - juggling
44
What did teaching 60 year olds juggling result in (Boyke et als study)
Increases in grey matter in the visual cortex, although when practicing stopped these changes reversed
45
What was the aim of Maguire et als plasticity study? AO1
To investigate whether changes in the brain could be detected because of extensive experience of spatial recognition
46
What was the sample of Maguire et als taxi study?
16 male London taxi drivers
50 males who didn’t drive taxis
47
What did Maguire et al use to measure the ammount of grey matter in taxi drivers and control groups brains
MRI scanner
48
What did Maguire et al use to measure the ammount of grey matter in taxi drivers and control groups brains
MRI scanner
49
What were the findings of Maguire et als plasticity study? AO1
The posterior hippocampus ( spatial and navigational skills) was larger than those of control group.
Posterior hippocampus volume was positively correlated with the ammount of time they had been a taxi driver
50
What are the evaluation points of Maguire et als plasticity study? AO3
+ highly empirical
- population validity
- evidence is correlations
51
How is it a strength that Maguire et als study is highly empirical? AO3
P: Maguire research is highly empirical
E: brain scans provide objective evidence to show that cab drivers she studied did have a significantly greater volume of grey matter in the posterior hippocampus than a matched control group
E: this is a strength as these findings provide verifiable evidence for brain plasticity and so suggests that the conclusions drawn about brain plasticity are valid
52
How does Maguire et als study have low population validity? AO3
P: she only used a small sample of 16 London male taxi drivers
E: it is possible that the group of participants are not representative of the population
E: this means that maguires conclusion that the brain physically changes as a result of experience may not be valid. However, there is no evidence to suggest that her sample size was unrepresentative which suggests that a lack of population validity is not really an issue. However, since the sample only consisted of males it is possible that her findings are not applicable to females
53
How is it an issue that Maguire et als plasticity study produced correlations evidence? AO3
P: an issue is that the evidence is correlational
E: this means that she has not proven that the taxi drivers brains have changed as a direct result of their experience - might be due to another factor
E: however, the correlation between their occupation and enhanced grey matter was very clear, which suggest that, despite being correlational, maguires evidence is valid
54
What evidence is there to support the claim that plasticity does not decline sharply with age? AO3
P: there is evidence that plasticity does not decline sharply with age
E: bezzola et al demonstrated how 40 hours of golf training produced changes in neural representations of movement in participants aged 40-60, using FMRI scans. Researchers observed increased motor cortex activity in novice golfers compared to control group suggesting more efficient neural representations after training
E: this demonstrates that neural plasticity can continue throughout the lifespan
55
What is a limitation of plasticity of the brain? AO3
P: a limitation of plasticity is that it may have negative behavioural consequences
E: for example, 60-80% of amputees develop phantom limb syndrome. The continued experience of sensations in the missing limb as if it were still there, these sensations are usually unpleasant. They are thought to be due to cortical reorganisation in the somatosensory cortex
E: this suggests that the brains ability to adapt to damage is not always beneficial
56
What does functional recovery refer to?
Functional recovery refers to a form of plasticity following trauma where the brain redistributes or transfers functions from damaged areas to undamaged areas
57
Neuroscientists suggest at first this can occur quickly following trauma but ___ ____ after several months. At this point the individual may require _____
1. Slow down
2. Rehabilitation
58
What happens to the brain during recovery?
The brain rewires itself by forming new synaptic connections close to area of damage and secondary pathways are unmasked to enable functioning to continue
59
What are the 3 structural changes in the brain which support recovery?
1. Zonal spouting
2. Denervation super sensitivity
3. Recruitment of homologous area on the opposite side of the brain
60
Define Axonal spouting
The growth of new nerve endings which connect with other undamaged nerve cells to form new neuronal pathways
61
Define denervation super sensitivity
Axons that do a similar job to the damaged areas are armoured to a higher level to compensate. However this can have unfortunate consequence of over sensitivity
62
What is an example of recruitment of homologous areas on the opposite side of the brain?
If the Broca’s area was damaged on the left side of the brain then the right sided equivalent would carry out its functions. Depending on how severe the brain damage is the functionality may shift back to the left side
63
What is an example of recruitment of homologous areas on the opposite side of the brain?
If the Broca’s area was damaged on the left side of the brain then the right sided equivalent would carry out its functions. Depending on how severe the brain damage is the functionality may shift back to the left side
64
What was the aim of Danelli et als functional recovery study?
To investigate if the brain can functionally recover after trauma by redistributing functions normally performed by the damaged area to other undamaged areas
65
What happened to EB (method) in Danellis functional recovery study?
At age 2 1/2 EB was operated on and had to have a large tumor removed from the left hemisphere of his brain, virtually removing the whole of his left hemisphere meaning all his linguistic abilities disappeared. He then underwent rehabilitation to recover his language skills
66
What were the results of EBs case study? (Functional recovery)
His language abilities started to improve at age 5 and when tested again at 17 and compared with ‘normal controls’ Danelli found that his right hemisphere had compensated for the left and that he was functioning well linguistically. However, they did find some areas which were not to the expected standard e.g. grammar and lack of spore when labelling objects in pictures
67
What was the conclusion of EBs case study? (Functional recovery)
Concluded that hemispheric lateralisation can be compensated for to atleast a basic degree by a non specialist hemisphere
68
What are the evaluation points of plasticity and functional recovery? AO3
+ practical application - neuro rehabilitation
- concept of cognitive reserve
- neural reorganisation is much greater in children than adults
69
What is a limitation of EBs case study? (Danelli functional recovery) AO3
P: case studies of individual are by nature unrepresentative. This is because there is no certainty that they are typical of population from which they are drawn
E: consequently, we cannot be certain that the functional Brian recovery demonstrated by EB would occur in other human beings - older people in particular
E: this study does not prove that functional recovery is possible
L: however, there is no evidence to suggest that EB is un representative and hence is study of Danelli et al provides reasonable evidence in support of this theory
70
What is the practical application of functional recovery? AO3
P: a strength of functional recovery is its real word application, contributing to the field of neuro rehabilitation
E: following illness of injury to the brain spontaneous recovery tends to slow down after a number of weeks so forms of physical therapy may be required in order to maintain improvements in functioning
E: the success of such therapies suggest that the theory and the research underpinning it are valid. It shows that research into functional recovery is useful because it helps medical professionals know when interventions need to be made.
L: however, it also shows that, even though the brain may have the capacity to fix itself to some extent, this process requires further intervention if it is to be completely successful
71
How is the concept of cognitive reserve a limitation of functional recovery? AO3
P: one limitation of functional recovery is that the level of a persons educational attainment may influence how the brain functionally adapts after injury
E: Schneider et al discovered that the more time brain injury patients had spent in education thebfreter their chances of a disability free recovery (DFR). 40% of those who achieved DFR had more than 16 years in education whereas 10% had less than 12 years
E: this is a limitation because it implies that people with brain damage who have less cognitive reserve are less likely to achieve full recovery, suggesting that there is an individual difference in the success of functional recovery of the brain
72
What are the 6 steps of synaptic transmission?
1. Action potential reaches axon terminal
2. Action potential stimulates release of neurotransmitters from synaptic vesicles
3. Neurotransmitters carry signal across synaptic gap and bind to receptor cells on post synaptic cell
4. Once receptors on post synaptic cell have been activated they produce excitatory or inhibitory effects
5. Summation occurs - net effect of EPSPs
6. If net effect is excitatory the post synaptic cell is more likely to fire / id net effect is inhibitory then the post synaptic cell is less likely to fire
73
Define the endocrine system
One of our bodies major information systems which instructs glands to release hormones directly into blood stream, carried towards target organs
74
Define gland
An organ in the body which sythesises substances such as hormones
75
Define hormones
Chemical substances that circulate in the blood stream and only affect target organs
76
What is the function of the pituitary gland?
Produces ACTH which influences the release of hormones from other glands to regulate the endocrine system. Known as the master gland
77
What is the function of the pineal gland?
Produces melatonin which regulates sleep patterns
78
What is the fight or flight response?
The way an animal responds when stressed. The body becomes aroused. Fight or flight response is generated from the autonomic nervous system, specifically the sympathetic branch and is a reflex response designed to help an individual manage physically when under threat, helping the individual react quicker and facilitate optimally
79
What is adrenaline?
A hormone produced by the adrenal glands as part of the bodies immediate stress response. Adrenaline has a strong effect on the cardiovascular system
80
Define localisation of function
The belief that specific areas of the brain are responsible for different behaviours / cognitions
81
What are the 4 sections of the brain?
1. Frontal lobe
2. Temporal lobe
3. Parietal lobe
4. Occipital lobe
82
What are the 6 functionally specialised areas of the brain?
1. Motor cortex
2. Somatosensory cortex
3. Visual cortex
4. Auditory cortex
5. Wernickes
6. Brocas
83
Where is the visual cortex located in the brain?
Occipital lobes
84
Where is the auditory cortex located?
Temporal lobes
85
Where is the motor cortex located?
Frontal lobes
86
Where is the somatosensory cortex located in the brain?
Parietal lobes
87
Where is brocas area located in the brain?
Left frontal lobe
88
Where is wernickes area located in the brain?
Left temporal lobe
89
What is the function of Broca’s area?
Speech production
90
What is the function of wernickes area?
Language comprehension
91
What are the evaluation points of localisation of function? AO3
+ case study - tan
- case studies are unrepresentative
- contradictory evidence - lashley
+ counterpoint - lashleys study was done using animals
92
How is the case study of tan supporting evidence of localisation of function? AO3
P: a strength of localisation of function is that it is supported by Brocas case studies.
E: broca studied a patient who could only speak one word (tan) but could easily understand speech. After his death Broca performed an autopsy and discovered damage to an area in the frontal lobe, now referred to as Broca’s area. Broca investigated 12 more cases similar to Tan and found damage in the same area of the brain. Broca concluded that this area was responsible for speech production
E: this is a strength of localisation of function since the case study demonstrates how different functions are located in specific areas of the brain
93
What is the counterpoint of Tan as evidence for localisation of function? AO3
P: case studies of individuals are unrepresentative by their nature and therefore unrepresentative. This is because there is no certainty that they are typical of the population of which they are drawn
E: consequently we cannot be certain that the localisation of brain function demonstrated by the Tan case study would be apparent in other human beings
E: therefore Tans case study does not prove that brain function is localised in the way the theory suggests
L: however, as broca found 13 cases demonstrating localisation of function this can be seen as reasonable evidence that specific areas of the brain are responsible for different behaviours
94
How is Lashleys study contradictory evidence of localisation of function? AO3
P: a limitation of the theory of localisation of function is that there is evidence to suggest that the theory is not correct
E: Lashley removed areas of the cortex (ranging from 10% to 50%) in rats which were learning a maze. No area was proven to be more significant in terms of the rats ability to learn the maze but the process of learning appeared to require every part of the cortex rather than a specific area
E: this contradicts localisation of function because it suggests that some functions such as learning are too complex to be localised and require the whole brain which supports the holistic theory.
95
How is Lashleys study using animals a weakness of the study? AO3
P: a limitation of Lashleys work relates to extrapolation as we cannot be sure that studies including rats can be applied to humans
E: this is because, despite both being mammals, the brain of a human is more sophisticated than one of a rat
E: as such it would seem to be the case that the research demonstrates that localisation of function is not apparent in rats but this does not disprove the theory in humans
L: in balance Lashleys work does not disprove the theory in humans but may suggest that the theory is flawed
96
Define corpus callosum
Bundles of nerve fibres which connect the right and left hemisphere
97
Which hemisphere is language predominant in?
Left
98
In which hemisphere are experiences, such as facial recognition, located in?
Right
99
Define endogenous pacemakers
Internal body clocks that regulate many of our biological rhythms
100
Define exogenous zeitgebers
External factors in the environment that reset our biological clocks through entrainment
101
What is the suprachiasmatic nucleus (SCN)?
A tiny bundle of nerve cells which is influential in maintains circadian rhythms. Connected to the eyes and revives information about light which enables the biological clock to adjust
102
What was Decoursey et als study into SCN?
Destroyed SCN connection in brains of 30 chipmunks. When returned to natural environment they were observed for 80 days and it was found that their sleep wake cycle had disappeared which led to a significant amount of the chipmunks being killed by predators
103
What was Morgan et als study into the SCN?
Morgan et al bred a strain of hamsters so they had a circadian rhythm of 20 hours instead of 24. SCN neurons from abnormal hamsters were transplanted into brains of normal hamsters. The normal hamsters then displayed the same abnormal circadian rhythms, demonstrating that the SCN had imposed the pattern.
In a reverse experiment, SCN from normal hamster was implanted into an abnormal hamster and the circadian rhythm changed to 24 hours
104
What are the evaluation points of animal studies into the SCN? AO3
- extrapolation
105
How is extrapolation a limitation of animal studies into SCN? AO3
P: issues with extrapolation
E: not certain that transplanting the SCN neurons into human brains would have the same effect since human brains are more sophisticated than hamsters
E: this means any conclusions drawn from research should be treated with caution
106
How are endogenous pacemakers hard to study? AO3
P: endogenous pacemakers are essentially impossible to study in isolation from other factors which may effect the sleep wake cycle
E: even Siffre used artificial light which may have reset his biological clock
E: this means it is very difficult to process the significance of the role played by endogenous pacemakers in the sleep wake cycle
107
Are are the 2 exogenous zeitgebers in the sleep wake cycle?
1. Light
2. Social cues
108
Define entrainment
An individuals chronobiological, physical and behavioural relationship with their environment
109
What are the evaluation points of endogenous pacemakers and exogenous zeitgebers? AO3
- inconsistent environmental effect
- case study against
- biological reductionism
110
How do EZs have an inconsistent effect in different environments? AO3
P: EZ do not have the same effect in all environments
E: for example, in the artic curcle, who spend 6 months in total darkness have the same sleep wake cycle all year round
E: this suggests that EPs are more important in regulating the sleep wake cycle E
111
What case study is there against EZs? AO3
P: a number of case studies suggest that the effect of EZs on the sleep wake cycle has been exaggerated
E: for example, a case study conducted by Miles found that a young man blind from birth had an abnormal circadian rhythm of 24.9 hours despite exposure to social cues such as regular meal times
E: this suggests that social cues alone are insufficient to determine the sleep wake cycle and that other factors must be involved
112
How are EPs and EZs biologically reductionist? AO3
P: research into role of EPs and EZs in the sleep wake cycle can be considered biologically reductionist
E: for example, the behaviourists would maintain that bodily rhythms are influenced by other people and social norms, such as sleeping when it is dark as it would be impossible to conduct normal daily routine during the night
E: consequently, the research discussed above could be criticised for being biologically reductionist as it emphasises the role of biological mechanisms and fails to consider alternative influences on the sleep wake cycle
113
What are the 3 types of biological rhythms?
1. Circadian
2. Ultradian
3. Infradian
114
What is a circadian rhythm?
A biological rhythm that lasts about 24 hours, which regulates several bodily processes such as the sleep wake cycle
115
What is the sleep wake cycle?
The sleep wake cycle is controlled by the SCN and dictates when we should be sleeping / awake.
The circadian rhythm experiences dips and rises with the strongest sleep drives being 2-4 am and 1-3pm. The free running internal circadian rhythm clock maintains a cycle of around 24-25 hours
116
What was the aim of Siffres study?
To investigate the duration of circadian rhythms in particular the sleep wake cycle
117
What method did Siffre used to investigate circadian rhythms?
Siffre isolated himself from all daylight by spending 6 months isolated in a cave with only artificial light to help him navigate. He had no clock or reference to time but did have limited verbal contact with outside world
118
What results did Siffre gain from his study into Circadian rhythms?
His internal body clock was allowed to free run and was at first erratic. Eventually the cycle settled to 25/30 hours and he continued to sleep on a regular schedule. However he did lose time of how long he had been in the cave
119
What did Siffre conclude from his study into circadian rhythms?
In the absence of EZs, circadian rhythms are roughly maintained which supports the existence of an internal body clock. However it does suggest that EZs are vital for keeping an individual to a 24 hour clock
120
What are the evaluation points of circadian rhythms? AO3
+ supported by Siffres study
- is a case study
+ practical application for shift work
- artificial light does affect circadian
121
How is Siffres research supporting evidence of the circadian rhythm? AO3
P: siffre’s research supports the claim that humans have a circadian rhythm that lasts approximately 24 hours and is governed by the endogenous pacemaker
E: siffre found that when he isolated himself from daylight and his internal body clock was allowed to free run, it eventually settled into a sleep wake cycle of 25-30 hours
E: this is a strength of the endogenous pacemaker theory because his results suggest that in the absence of exogenous zeitgebers, circadian rhythms are roughly maintained which supports the existence of an internal body clock
122
What’s the issue with Siffres research being a case study? AO3
P: Since siffre is a sole participant his research has low population validity
E: consequently, we cannot be certain that his findings in relation to the fact EPs and EZs work together are valid and apply universally
E: however, there is no reason to believe that Siffre is not a normal member of the human race and that his findings do indeed apply to others
123
How was artificial light a limitation of Siffres study? AO3
P: a limitation of Siffres study is that he had access to artificial light which he assumed would not affect his circadian rhythm
E: however, czeizler managed to alter circadian rhythms down to 22 hours and up to 28 hours by using dim artificial light alone
E: this is a limitation of Siffres findings because it may of been the artificial light maintaining his sleep wake cycle so his conclusion of a free running circadian rhythm of 24 hours would not be valid
124
How does research into circadian rhythms have practical applications? AO3
P: a strength of research into circadian rhythms is that they have practical applications into shift work
E: research has demonstrated that night workers engaging in shift work experience a period of reduced concentration at 6 in the morning which leads to mistakes. Furthermore, research has shown a relationship between shift work and poor health such as shift workers being 3x more likely to develop a heart disease
E: this is a strength because research into the sleep wake cycle may have economic implications in terms of how to best manage worker productivity and safety
125
Define infradian rhythm
A type of biological rhythm that has less than one cycle in 24 hours
126
What are the 2 examples of infradian rhythms?
1. Season affective disorder (SAD)
2. Menstruation
127
What was the aim of McClinton and sterns study into infradian rhythms?
To investigate if menstrual cycles can be affected by exogenous zeitgebers such as female pheromones
128
What method was used by McClinton and stern?
A sample of 29 women with irregular periods was used. Samples of pheranomes was gathered from 9 women via cotton pads under their armpits which they wore for atleast 8 hours. The pads were then treated and frozen before being rubbed on the upper lip of other participants
129
What results were gained by McClinton and Stern?
68% of women experienced changes to their cycle which brought them closer to the odour donor
130
What was concluded in McClinton and Sterns study?
A women’s menstrual cycle can be altered by communication with pheromones / exogenous zeitgebers
131
What are the evaluation points for infradian rhythms? AO3
+ supported by McClinton and Stern
- counter point - sample size
- counterpoint - correlational
- only 68% of women experienced changes
132
How is McClinton and Stern supporting evidence for infradian rhythms? AO3
P: supported by research
E: McClinton and Stern applied pheromones obtained from 9 women to 20 participants. 68% of women experienced changes to their cycle which brought them closer to the odour donor, meaning the menstrual cycle can be altered by exogenous factors
E: this is a strength because it demonstrates how pheromones play an important part in the timing of the menstrual cycle and is objective evidence that infradian rhythms do exist
133
Define ultradian rythm
A biological rhythm where there is more than one cycle in 24 hours
134
What is an example of an ultradian rhythm?
The sleep cycle
135
What happens in stage 1/2 of the sleep wake cycle?
Known as light sleep where a person can be easily woken. Brain wave patterns start to slow down
136
What happens in stage 3/4 of the sleep wake cycle?
Known as a deep sleep so it is difficult to wake somebody. Brain waves are even slower
137
What happens in stage 5 of the sleep wake cycle?
REM sleep where the body is paralysed but brain activity increases. REM has been correlated with dreaming through research
138
What was the aim of Dement and kleitmans study into ultradian rhythms?
To investigate brain activity change throughout night time sleep
139
What method was used by Dement and Kleitman?
7 males and 2 females were asked to report to a laboratory at bed time where they were connected to an EEG which took measurements throughout their sleep. Participants were asked to not drink caffeinated drinks.
140
What were the results of Dement and Kleitmans study?
They found that All participants had period of REM every night and when woken during REM period the participants dream recall was better than if they were awoken during other stages
141
What was concluded from Dement and Kleitmans study?
The study concluded that sleep follows a typical pattern throughout the night
142
What are the evaluation points of ultradian rhythms?
+ supported by research - Dement and Kleitman
- small sample size
+ EEG is an objective measure
143
How is Dement and Kleitman supporting research of ultradian rhythms? AO3
P: a strength of the theory that humans have ultradian rhythms is that it is supported by research
E: for example, Dement and Kleitman conducted a study where 7 males and 2 females were connected to an EEG during their sleep. It was found that every participants had periods of REM every night and that dream recall was better when woken during period of REM than other stages
E: this is a strength since it demonstrates how sleep follows a typical pattern throughout the night and suggests that ultradian rhythms do exist in humans
L: replications of similar studies have produced similar results
144
How is it a limitation that supporting research of ultradian rhythms have low sample sizes? AO3
P: Dement and Kleitman only had a small sample size of 9 people of which only 2 were female. This means that the population validity of the sample is limited
E: as such their conclusion that sleep follows a typical pattern throughout the night may be unrepresentative of a wider population and hence may not apply to the sleep cycle of others
E: however there is no evidence that this is the case since it’s reasonable to argue that the small sample size is not sufficient reason to discount the findings or conclusions of this research.
145
How is it a strength of Dement and Kleitmans research that EEG is an objective measure? AO3
P: a strength of Dement and Kleitmans research is that EEGs provide highly empirical data
E: EEGs provide objective evidence to show that sleep follows a typical pattern throughout the night
E: this is a strength because these findings provide verifiable evidence for ultradian rhythms
146
Outline the summary of the use of FMRI scans
FMRI scans use magnetic field and radio waves to monitor blood flow. When an area of the brain is active it requires more energy from haemoglobin in blood so increased blood flow. Regions of brain can be compared by using a baseline task
147
Outline the summary of the use of EEG
Electrodes are placed on the scalp to detect neuronal activity below where they are placed
148
Outline summary of the use of ERPS
Electrodes are placed on scalp to detect neuronal activity below where they are placed in response to a stimulus
149
Outline the summary of post mortem examinations
The brain is examined after death to try and correlate structural abnormalities.
150
What are the main evaluation points of the ways of studying the brain?
1. Invasive or non invasive
2. Temporal resolution
3. Spatial resolution
4. Cost / sample size
151
Which ways of studying the brain are non invasive?
1. FMRI
2. EEG
3. ERPS
152
Which ways of studying the brain have good / bad temporal resolution?
FMRI = poor 1-4 seconds
EEG = good 1-10 milliseconds
ERPS = good 1-10 milliseconds
Post Mortem = after death
153
Which ways of studying the brain have accurate spatial resolution?
FMRI = very accurate 1-2mm
EEG = only reasonably accurate since electrodes pinpoint superficial areas of the brain
ERPS = only reasonably accurate since electrodes pinpoint superficial areas of the brain
Post mortem = allows more detailed examination of brain anatomy by allowing research into deeper regions of the brain.
154
How do the sample sizes differ in the ways of studying the brain?
FMRI = limited sample size due to cost
EEG = increased sample size due to cost
ERPS = increased sample size due to cost
Post Mortem = limited sample size due to special permission being required
