Brain Flashcards
1
Q
Describe dendrites within the structure of neuron
A
The cell body of the neuron contains the cell nucleus.
Attached to the cell body are dendrites (branches at the top) that receive messages from other neurone to trigger an action potential within the cell.
2
Q
Describe the axon within the structure of the neuron
A
The axon is attached to the cell body, it is a long branch of nerve fibres that connect the cell body to the end of the neuron which passes the action potential towards the axon terminals.
3
Q
Describe axon terminals within the structure of a neuron
A
At the end of the axon terminals are terminal buttons (where the nerve impulse becomes a chemical message).
Terminal buttons are bulb shape structures that contain tiny sacs called vesicles that store neurotransmitters ready for the next stage of neural transmission.
4
Q
What is the role of the neuron?
A
The neurons role is to pass messages between neurons using neurotransmitters to enable behaviour, thinking and emotions to be transmitted and to enable the working of the brain.
5
Q
Describe the role of neurotransmitters
A
Neutrals mutters are chemicals that pass messages from one neurone to the next. This allows the brain to process thoughts and memories.
6
Q
What is dopamine?
A
It is a neurotransmitter associated with pleasure feelings. It is associated with addition, as individual’s carry out actions to achieve the pleasure feeling. It is linked to drug addiction.
7
Q
What is serotonin?
A
It is a neurotransmitter associated with mood control. Low levels are associated with depression and anxiety. It is also involved with functions such as sleep and regulating body temperature.
8
Q
What is reuptake?
A
The process when any neurotransmitters not absorbed by a receptor are absorbed again by the presynaptic neuron.
9
Q
What is the function of synaptic transmission?
A
A neurotransmitter crosses the synaptic gap/synapse.
When the action potential reaches the axon terminal of the presynaptic neuron, the terminal button releases the neurotransmitter from the vesicles into the synaptic gap.
On the dendrites of the postsynaptic neuron are receptors which receive the neurotransmitters.
Receptors are shaped so only one type of neurotransmitter can fit into them.
When the receptor detects the neurotransmitter it is absorbed and the message is passed on.
10
Q
What is the role of the central nervous system?
A
The central nervous system is made up of the brain and the spinal cord.
It guides our behaviour, co-ordinating the body’s activities.
The spinal cord connect the brain to the rest of the body and allows messages to be passed from the body to the brain and from the brain to other parts of the body.
11
Q
Describe recreational drugs
A
Recreational drugs are those that are used in the absence of medical grounds, but are taken by users for pleasure.
They are referred to as psychoactive drugs because they have an effect on the central nervous system which changes our mood perception or conscious experience.
Examples include nicotine, alcohol, cocaine, cannabis
12
Q
What is the general effect if recreational drugs on transmission in the CNS
A
Most drugs have a specific mode of action at the synapse.
Drugs hijack the rewards system and produce pleasurable feelings without any adaptive function.
Most psychotic drugs of addiction work on the dopamine system.
13
Q
What is the dopamine system?
A
A pathway in the brain which operates neurotransmitter dopamine the release of which leads to feelings of pleasure.
14
Q
Describe nicotines effect in the transmission process in the CNS and how it can lead to addiction
A
Nicotine mimics the actions of a natural neurotransmitter, acetylcholine.
Nicotine bonds to a certain type of acetylcholine receptor called nicotinic receptors.
This causes an impulse in the neuron releasing more neurotransmitters, in this case dopamine.
Over time the brain reacts to this increase in dopamine by decreasing the number of dopamine receptors on the post-synaptic neuron to counteract the effect.
When nicotine is no longer present, because of the reduced number of dopamine receptors on the post-synaptic neuron the level of dopamine drops lower than would be for normal brain functioning.
This means more dopamine is required to stimulate the postsynaptic neuron to a normal level leading to desensitisation.
This leads to addiction because nicotine is now needed just to maintain the normal levels of dopamine in the brain.
15
Q
What is desensitisation?
A
When more of a substance is required to achieve the same stimulation due to changes at the synapse.
16
Q
State two strengths of arguments about drugs effects on transmission
A
👍Supporting evidence shows how recreational drugs create excess dopamine to give a ‘high’. This includes studies that found a pleasure centre in the brain of rats and studies that found an effect of cannabis in the hippocampus of mice.
👍There is credibility suggesting that recreational drugs firstly create more dopamine in the reward system, so give pleasure, and secondly have a desensitising effect leading to a tolerance addiction. This is because we observe people who take recreational drugs who at first experience great pleasure but then become addicted an need more to experience the same effects.
17
Q
State two weaknesses of arguments about drugs effects on transmission
A
👎It is hard to study the mode of action of recreational drugs at the synaptic level as brain scanning techniques need to be more sophisticated. For example the focus is currently is in transmitter that are more easily studied so they are the ones conclusions will be made about.
👎The majority of scientific studies on recreational drugs are carried out using animal era therefore suffer from low generalisability. There are differences in the functioning of animal brains in comparison to human brains, this means it is not always possible to conclude findings represent the more complex human brain.
18
Q
How many lobes is the brain made up of? (Name them)
A
The temporal lobe
The parietal lobe
The occipital lobe
The frontal lobe
19
Q
What can damage to the frontal lobe lead to?
A
Damage to the frontal lobe has been linked to aggression. For example Phineas Gage suffered damage to the prefrontal cortex following an accident which seemed to affect his temperament.
20
Q
What is lateralisation?
A
When the brain is in two halves called hemispheres.
21
Q
What does bilateral mean?
A
When brain structures are the same across two hemispheres, such as the lobes.
22
Q
Describe the prefrontal cortex
A
It is a brain structure involved in aggression.
A lot of dopamine, serotonin and norepinephrine connections are found in the prefrontal cortex. These neurotransmitters link to emotions, which is evidence that this area of the brain has a role in emotions.
The prefrontal cortex is in both hemispheres of the brain. On the left side it appears to have a role in regulating negative emotions from the amygdala in the limbus system.
23
Q
What can damage to the prefrontal cortex lead to?
A
Damage to the prefrontal cortex might leave someone unable to plan long-term and lead them to immediate rewards. It could also mean that they are unable to control aggressive reactions.
24
Q
What is the difference between an active and a less active prefrontal cortex?
A
An active prefrontal cortex regulates aggressive behaviour.
In a less active prefrontal cortex aggressive urges continue.
25
What is the role of the limbus system?
The limbus system has a role of self preservation for example, structures in the limbus system control our temperature and our flight or fight response.
26
What system is the limbus system linked to?
It is linked to our autonomic systems which respond automatically to danger rather than in a planned way.
27
What is the role of the hypothalamus in the limbic system?
The hypothalamus has a balancing role. It regulates our hunger and thirst as well as our response to pain, anger and sexual satisfaction.
28
What is the role of the amygdala in the limbic system?
The amygdala is the centre for identifying threat and it's role is self-preservation.
It is thought to have a role in arousal, aggression and the fight response.
29
Describe cocaines effect on the transmission process in the CNS
Cocaine blocks the binding site on the reuptake receptor and stops the reuptake of dopamine back into presynaptic neuron.
This means there is excess dopamine in the synapse that leads to over-stimulation at the postsynaptic receptors.
More dopamine than usual in the reward pathway leads to feelings of euphoria.
Over time the brain reacts to this over-stimulation of the dopamine receptors by reducing the number of receptors in the post-synaptic neuron to counteract the effect.
This means more dopamine will be required to stimulate the postsynaptic neuron to normal level leading to desensitisation.
This leads to addiction because cocaine is now needed just to maintain the normal levels if dopamine in the brain.
30
What happens if the amygdala is stimulated using an electric current?
Aggression is shown.
31
What happens when the amygdala is removed?
The subject becomes more passive and unresponsive to fear.
32
What does a reduction in the size of the amygdala lead to?
An individual is three times more likely to commit a violent crime.
33
State two strengths of using brain functioning as an explanation for aggression
👍There is supporting evidence linking brain structure to aggression from Raine et al's (1997) study. They found murderers who pleaded not guilty on the grounds of insanity had less activity in the prefrontal cortex than a control group of non-murderers.
👍Brain structure studies have increased reliability with neuroimaging techniques such as PET and fMRI scans. Greater precision and standardisation of these techniques have allowed structures of the brain to be more accurately and consistently measured.
34
State two weaknesses of using brain functioning as an explanation for aggression
👎The findings if the animal studies cannot be generalised to humans because of fundamental differences between humans and animals and are therefore not representative. Animals do not have the same prefrontal cortex as humans for example is it smaller in animals.
👎There are ethical concerns with the use of animals in studies that may have caused physical and psychological harm. Some would argue that studies such as Downer's that involved brain lesions in monkeys are immoral and harmful to the animals.
35
State the aim of Raine et al's classic study
The study aimed to how that brains of murderers who pleaded not guilty by reason of insanity were different from brains of non-murderers.
36
State 4 procedure points of Raine et als classic study
- The experimental group included 41 criminals pleading NGRI who had been charged with either murder or manslaughter. The control group was also made up of 41 pps.
- Each murderer was matched to a pp from the control group in terms of sex and age as well as similarities in other ways eg there were 6 control group pps with schizophrenia.
- All pps were given a continuous performance task which consisted of a sequence of blurred numbers to focus on.
- After a further 32 mins on the CPT a PET scan was completed to measure the metabolic rate in different areas of the brain in order to look at activity levels in those areas.
37
State 2 results of Raine et al's classic study
They found that murderers who pleaded NGRI had less activity in the prefrontal areas of the brain.
There was no difference in the activity of the temporal areas of the brain between the criminals and the control group.
38
State the conclusions of Raine et al's classic study
These brain differences have been associated with behavioural changes that could be related to violent behaviour. For example, dysfunction in the prefrontal cortex has been linked to impulsivity, lack of self-control and inability to learn the consequences of behaviour.
39
State two strengths of Raine et al's classic study
👎The sample was high in validity as it was the latest sample of secretly violent offenders to e studied in this way and compared to matched control reducing participant variables. The murderers had already been referred to the imaging centre to gain evidence for their NGRI pleas and so this was a naturally occurring behaviour rather than something that ha been introduced by the research process.
👍The study was highly objective as it used PET scanning which can be interpreted by a number of different researchers in the same way without introducing researcher bias to the results. This in turn increases the reliability of results as the scans are easy to replicate and the procedures for carrying out scans can e easily controlled.
40
State two weaknesses of Raine et al's classic study
👎The study has low generalisability as the experimental group was so specific eg murderers pleading NGRI. The findings are not representative of all offenders, even though it was violence that was being studied.
👎There are ethical concerns as the murderers were pleading NGRI. We may need to question their capacity to provide consent for their participation in the study if indeed they were truly experiencing mental health issues.
41
What do genes do?
Genes guide a lot of our characteristics and how we are. 50% inherited from our mother and 50% inherited from our father, which make up our genotype.
42
Describe how characteristics are inherited through evolution
Evolution is how inherited characteristics in organisms change from generation to generation. Changes in inherited characteristics lead to differentiation between species, it can evolve in positive or negative ways.
43
Describe natural selection
Darwin's theory of natural selection refers to the process in which organisms better adapted to their environment are healthier, live longer and reproduce more frequently passing on their genes.
44
Describe genetic mutation
Genetic mutation refers to a permanent change in the gene sequence, which can come from a virus or damage due to radiation. Mutations can involve large new sections of DNA and these mutations can be advantageous.
The advantageous mutations will change the gene pool. Those that benefit organisms, increase the chances of reproduction and do the mutated gene would then be inherited.
This type of mutation can lead to new species vein produced.
45
Explain aggression using evolutionary theory
Males that were naturally more aggressive when their offspring and resources were threatened or when hunting had an adaptive advantage. This also gave them an advantage in terms of mate choice.
The theory suggests that aggression in females would be a disadvantage for females who spend long periods pregnant, breast feeding and caring for vulnerable young.
Aggression towards another person who is a threat to a male-female pair makes sense in terms of evolution. Jealousy and resulting aggression can be seen as a survival trait.
46
State two strengths of using evolution theory to explain behaviour
👍Darwin's theory is reductionist as it reduces behaviour to genes that guide it and so the focus can be on the individual's genotype. Darwin was able to observe inherited behaviours and characteristics. Reducing to observable features means observations can be careful and supported by evidence.
👍There is supporting research evidence for evolutionary explanations of aggression from Buss & Shackleton (1977) who found that men feeling threatened in a relationship tended to give in to a female and were threatening to other makes around. Both these strategies would aid the survival of the male's genes.
47
State two weaknesses of using evolution theory to explain behaviour
👎Darwin's theory is reductionist. By focusing on specific aspects of behaviour, he has neglected the bigger picture and apparent contradictions. Whilst he focused on the generic transmission of characteristics, he did not take into account how behaviour can be learned thorough observation and by association.
👎Opposing theory of aggressive behaviour comes from Dollard et al (1939) who suggest that aggression in humans come from frustration from environmental influences. This can be seen as an alternative explanation to natural selection.
48
Describe what hormones are
Hormones are chemical messengers carried in the blood that transmit information all around the body.
49
How are hormones different to neurotransmitters?
Hormones take longer to work than neurotransmitters and tend to be used to effect longer-term changes.
50
Where are hormones produced?
They are produced in the endocrine system.
| They also come from men's testes and women's ovaries as well.
51
What makes up the endocrine system?
The thyroid, adrenal and pituitary glands make up the endocrine system.
52
Where is the pituitary gland located and what is it's role?
The pituitary gland is located in the brain and has an important role in the production of hormones.
53
What is cortisol?
It is a hormone released from the adrenal gland.
| It is needed to combat stress and maintain healthy blood pressure.
54
What is the role of testosterone?
Testosterone is produced in the testes.
| It has a role in maintaining the sex drive and producing sperm.
55
What is the role of oestrogen?
It is produced in the ovaries.
| Has a role in the menstrual cycle and development of breasts.
56
Describe how and when hormones affect behaviour
Hormones affect people at around puberty and hormones affect mood both during the menstrual cycle and around the menopause.
Hormones affect our behaviour either directly (sleeping) or indirectly (stress regulation and mood).
57
Give two studies that show how hormones explain aggression
Dabbs et al (1987) measured levels of testosterone in the saliva of 89 male prisoners involved in violent and non-violent crime. 10/11 prisoners who had commuted violet crime had high levels of testosterone. These results suggest that a high level of testosterone links to aggressive behaviour in humans.
Adelson (2004) reported that rate displayed a feedback loop between activity in the aggression systems in their rain and hormonal stress response. Raised stress hormones went with raised stimulation of the aggression centre of the brain and vice versa. In humans this could explain why aggression in humans can lead to stress.
58
State two strengths of using hormones to explain human behaviour
👍Studies that correlate hormone levels and aggression are high in reliability. They use careful controls and scientific methods which mean that the studies produce consistent results. Dabbs et all (2013) used standardised measures to test hormones found in saliva.
👍Findings from animal studies such as Adelson's study of rats are generalisable to human behaviour. The hypothalamus and limbus systems in humans and rodents are similar enough for generalisations to be made.
59
State two weaknesses of using hormones to explain human behaviour
👎It is difficult to establish cause and effect relationships between hormone levels and aggression, particularly in the study of humans. For example correlations suggest a link between testosterone and cortisol and aggression but there could be unknown variables causing both of these to occur.
👎Results from animal studies are difficult to generalise to humans. Issues include differences in motivation and planning between humans and animals. Studies of animals are likely to be in and unnatural environment which makes the findings difficult to generalise beyond the study and to humans.
60
State the conclusion of using hormones to explain human behaviour
Biological explanations of human behaviour that focus on the role of hormones have scientific credibility as the studies used to support explanations use scientific methodology and produce results that are highly reliable.
61
Why is Freud's psychodynamic explanation within biological psychology?
Freud's psychodynamic theory is not a biological explanation. It is presented here as a contrast to the biological explanation for human behaviour and aggression.
62
What parts did Freud believe the mind was made up of?
Conscious mind
Pre conscious mind
Unconscious mind
63
Describe the conscious mind within Freud's theory
This consists of what we know or what is accessible to us right now.
Eg answering exam questions
64
Describe the pre conscious mind within Freud's theory
It is information that we can make ourselves aware of but are not always held in the conscious mind.
Eg remembering things about your childhood because you saw an old photo
65
Describe the unconscious mind within Freud's theory
This is the information that we are not aware of and we cannot access.
The unconscious mind holds threatening thoughts and urges which are not made conscious to us.
These thoughts have to be forcefully repressed into the unconscious.
66
What did Freud believe were the three aspects of personality?
The id
The ego
The superego
67
Describe the id within Freud's theory of personality
The id exists right from birth and is the most basic part of the personality.
It is driven by the impulses of Eros and Thanatos.
It is the instructive part of the personality.
It operates the pleasure principle which means it demands the immediate gratification of its urges.
68
Describe the ego within Freud's theory of personality
Develops within the first 2-4 years.
It is the rational part of the personality.
Balances the demands of id and superego.
It operates the reality principle as it allows the child to realise that talking, explaining and asking is more effective.
69
Describe the super ego within Freud's theory of personality
It develops in the first 4-5 years.
It is made up of our conscience given to us by our parents and society. It is when we start to feel guilt.
It operates in the morality principle to help us understand what is right and wrong.
70
Describe cartharsis within Freud's theory of personality
Cartharsism is releasing aggression in a socially acceptable way.
It can be achieved by watching violent films or playing video games or sports such as boxing or rugby.
71
Describe repression within Freud's theory of personality
We repress hated or dislike, that isn't socially acceptable, into our unconscious.
This could be problematic in adulthood.
72
Describe the eros within Freud's theory of personality
Eros is our unconscious life instinct and is focused on self-preservation, enjoyment of life and sexual energy.
It will redirect Thanatos to turn our self destruction into aggression onto others.
73
Describe Thanatos within Freud's theory of personality
It is our unconscious death instinct which is our desire to reduce arousal, to reduce life and create destruction (death) which is directed towards the self.
74
Compare the psychodynamic explanation of aggression with the biological explanation focusing on internal structures
Both approaches focus on internal structures with cause aggression.
The psychodynamic approach states it is unconscious thoughts and urges which generate frustration which create aggressive behaviour, a cathartic process.
The bio approach focuses on brain structure and brain functioning for example the amygdala is responsible for our emotions and is an internal structure.
75
Compare the psychodynamic explanation of aggression with the biological explanation focusing on biological evidence
Both approaches have biological evidence to support their claims.
As brain scanning has become more widely used it has been claimed by the biological approach that the limbus system is used for emotions and not our rational thinking.
This also supports the psychodynamic idea that emotions and feelings such as urges and desires are unconscious and not part of our rational mind.
76
Compare the psychodynamic explanation of aggression with the biological explanation focusing on scientific credibility
The psychodynamic approach uses case studies as the main research method which involve gathering large amounts of qualitative data unique to the individual, making it hard to generalise the data to other people, lacking scientific credibility.
However the bio approach draws scientific data from quantitative scientific methods such as experiments, brain scans and animal studies which are highly controlled and reliable.
77
Give a conclusion comparing the psychodynamic explanation of aggression with the biological explanation
The psychodynamic approach highlights the role of the unconscious and urges in aggression.
However biological psychology looks for the actual structure in the body that is involved in the function of aggression, giving it more scientific credibility.
78
State two strengths of Freud's theory to explain aggression
👍Freud used valid data to generate his theories. He generated this data from case studies which were very detailed and in depth, he constantly amended his theories of the unconscious mind and personality.
👍Freud's theory has practical applications. His development f psychoanalysis was particularly useful in the treatments of those with mental disorders such as neuroses. It also shows how catharsis can be use to reduce aggressive behaviour in an individual by taking part in aggressive sports to reduce frustration.
79
State two weaknesses of Freud's theory to explain aggression
👎Freud's ideas lack scientific credibility. For example the unconscious, id, ego and superego are very difficult to measure via conventional scientific experiments and so canny be proved or disproved.
👎Freud's ideas are not generalisable. The data gathered I'd qualitative and specific to an individual, there lifted it it not representative of others and a theory should not be generated from such findings.
80
What are MZ twins?
Monozygotic twins have come from one fertilised egg and share 100% of their genes so they are identical.
81
What are DZ twins?
Dizygotic twins come from two fertilised eggs and share 50% of their genes so they are non-identical.
82
Describe the methodology of twin studies
Twins are compared to assess the effects of genes on a behaviour. If genetics is a more important influence than environment then we would expect MZ twins to he more similar than DZ twins in terms of a target behaviour such as personality.
Biological psychologists look at concordance rates between twins on a particular trait.
If the CR for a particular trait are higher for identical twins than non-identical twins, then it is likely genes play a strong part in the trait being studies.
83
What is concordance rates?
The likelihood that if one twin has a certain trait the other twin will also have that trait.
84
Describe the methodology of adoption studies
Adoption studies allow psychologists to separate genetic and environmental influences in behaviour by looking for similarities in behaviour between children and their biological and adoptive parents.
85
State one strength and one weakness of twin studies
👍There is a level of control. This is because MZ and DZ twins share their environments. There is therefore a natural control per environmental effects such as the home and school.
👎The validity of the method is questionable as there is a lack of environmental control. MZ twins have identical DNA but epigenetic modification has to be taken into account and they may grow and develop differently because of environmental influences.
86
State one strength and one weakness of adoption studies
👍Adoption studies can be longitudinal. This means developmental trends can be studied. The same group of children can be followed as they develop, so characteristics that coke as genes are triggered.
👎The validity of the method is questionable as there is a lack of environmental control. Families that adopt tend to be chosen to be as similar as possible to the biological families, so the environment may not be very different.
87
State the aim of Heston's adoption study (1966)
To see if schizophrenia has a genetic predisposition.
88
State 3 procedure points of Heston's adoption study (1966)
47 adults who had been adopted at birth because their biological mother had been diagnosed with schizophrenia were matched with 47 adults adoptees who's mothers were mentally healthy.
All pps had a personal interview as well as a mental health personality health to see it they had developed schizophrenia.
3 psychiatrists independently rated each pp.
89
State the results of Heston's adoption study (1966)
Incidence of schizophrenia in the general population is 1% and this was similar for those who were adopted with no family history of schizophrenia.
Five (10%) of the adopted children with schizophrenic mothers were later hospitalised with schizophrenia.
None of the control group developed schizophrenia.
90
State the conclusion of Heston's adoption study (1966)
News do appear to play a role in schizophrenia because the percentage of schizophrenic offspring of affected mothers was high even though they had not been brought up by their biological mother.
91
State two strengths of Heston's adoption study (1966)
👍The adoption study was high in validity because it gathered a large amount of qualitative data through personal interviews and the MMPI tests. This means the data fathers can be seen to be an accurate reflection of real life.
👍The adoption study gas scientific credibility as it successfully controls for the influence of the environment on the development of schizophrenia. This is done by studying pps who have schizophrenic mothers who were adopted at birth.
92
State two weaknesses of Heston's adoption study (1966)
👎The adoption study has low generalisability because most people are not adopted, which means that those who are adopted are not representative of the whole population. For example in Heston's study there may have been something different about these particular mothers and their babies that led to adoption.
👎The adoption study is reductionist as it simply describes differences found in the diagnoses of schizophrenia ester than explaining them. The study only shows that genetics has a role in the development of schizophrenia it does not explain what that role is.
93
State the aims of Brenden et al's contemporary study
To see if social aggression is caused by genes or the environment.
To see f presence of both social aggression and physical aggression in an individual can be explained by the same genetic or environmental factors.
To see if one type of aggression leads to another.
94
State 4 procedure points of Brenden et al's contemporary study
Pps were recruited from the Quebec Newborn Twin Study in Canada. The final sample consisted of 234 twins pairs.
Teachers complete a behaviour questionnaire for the twins in their class. They rate the child's physical and social aggression using standardised scales. The scores given by teachers for each statement was done on a 3 point scale (never/sometimes/often)
Peer ratings of the twins for physical and social aggression were gained by giving each child a booklet constraining photos of every child in the class. Peers were asks to circle 3 photos of children that matched 4 different behaviour descriptions.
And the end, each child had a physical and social aggression score based on teacher and peer ratings.
95
State the results of Brenden et al's contemporary study
On physical aggression MZ correlations were nearly twice as high as same sex DZ correlations for both teacher and peer ratings.
Aim 1: On social aggression MZ correlations and same sex DZ correlations were similar for both teacher and pear ratings.
2: children showing physical aggression did tend to show social aggression to.
3: Physical aggression may lead to social aggression but not the other way around.
96
State the conclusions of Brenden et al's contemporary study
There is a strong genetic component to physical aggression but not social aggression, which is more likely due to environmental effects.
Children who were physically aggressive were also more likely to display social aggression because of an interaction between genes and the environment.
97
State 2 strengths of Brenden et al's contemporary study
👍The study has high visits because measures of the twins aggressive behaviour was taken from two different sources, teachers and peers. This would eliminate or highlight any bias occurring.
👍The study has high reliability because teacher and peer ratings of the twins aggressive behaviour can be cross checked for consistency. As the ratings mostly agreed reliability was demonstrated.
98
State 2 weaknesses of Brenden et al's contemporary study
👎The study is low in generalisability because the sample size of 234 twin pairs was relatively small when looking at group comparisons. However a larger sample size would not have been practical when working with 6 year olds as each researcher had to record the data with each child individually which was a time consuming process. This means the sample is not representative of the whole population.
👎The findings lack internal validity as the researchers could not be 100% sure that the twin pairs were allocate correctly as MZ or DZ. this was because some of the twins zygosity was judged by appearance only. DNA test were not used on all of them. This means the researchers might not have been correctly separating and comparing the effects of genes and environment on aggression.
99
What is the key question for biological psychology?
What are the implications for society if aggression is found to be caused by nature not nurture?
100
State the description of the biological key question
The term aggression refers to a range of behaviours linked to emotion that can result in both physical and psychological harm to oneself, others or objects in the environment.
Humans may act aggressively due to nature. Nature refers to the effects of physiological factors such as brain structure, genes or hormone levels. Or nurture this is the result if something in their environment such as upbringing.
Footballers such as Suarez have gained a reputation for impulsive aggressiveness on the pitch. He has been accused of biting, kicking and punching other players.
It might be said that of aggression is caused by environmental factors then someone can choose to act differently.
If aggression is caused by biological factors, there is no choice to behave aggressively and consequently we perhaps should not blame individuals for behaving aggressively and should not punish.
101
Explain the biological key question using hormone levels
High levels of testosterone and low levels of cortisol have been linked to aggressive behaviour in humans and animals.
Dabs et al (1987) found that prisoners who had commuted violent crimes had higher levels of testosterone than prisoners who had committed non-violent crimes.
Hormones therefore have a role in aggressive behaviour which is part if our biological make up. This means it may not e appropriate to punish people for violent crime if it is beyond their control.
102
Explain the biological key question using brain structure
Aggression can be provoked in an animal if certain brain regions, like the hypothalamus are electronically stimulated.
This suggests that aggression comes from brain functioning therefore it has a biological cause and is in our nature.
The animal would not be blamed for the aggression response and perhaps humans who exhibit aggression for similar biological reasons should not be blamed or punished either.
103
Explain the biological key question using genes
The MAOA (warrior) gene has been linked to aggressive and impulsive behaviour.
McDermott et al (2009) found that people with a version of this gene that shows low activity, or low expression, may be more likely to react to provocation by showing aggression.
Genes are part of our biological make up and is by something that an individual can control. Society would not blame someone for the genes that they have inherited.
104
Describe correlation research
Correlation design is a quanta tube technique where two different variables are measured either using primary or secondary data to see if they show a relationship.
A positive correlation is where the two co-variables go up and down together. Eg as time spent revising increase so does exam success.
A negative correlation is where as one variable increase the other decreases. Eg as self esteem increases the rate of depression decreases.
Correlation coefficient is a measure of the direction (positive or negative) and extent/strength (range if a correlation coefficient from -1 to +1) of the relationship between two sets of scores.
105
State two strengths of using correlation research
👍Correlations are good for finding relationships at the start of an investigation between two variables that was not expected. This can lead to more expensive research in controlled conditions to identify cause and effect relationships.
👍They can be used to determine a relationship when it is not possible to carry out an experiment.
106
State two weaknesses of using correlation research
👎A correlation does not tell us about cause and effect. We do not know whether one variable caused anther to change.
👎Low validity as at least one of the variables often needs to be operationalised making it unnatural.
