biological psychology

Question 1

evidence for drugs affecting brain functioning

Answer 1

• Van de Oever- found changes in the medial prefrontal cortex in rats with heroin addictions.

Question 2

Evidence of limbic system in aggression

Answer 2

Charles Whitman- found to have a cancerous tumour in his hypothalamus near his amygdala. School shooting at the University of Texas.

Coccaro et al- studied a group of people with intermittent explosive disorder using FMRI (pictures of threatening and non threatening stimuli). Compared to control group, Ps who had IED had a greater amount of activity in their amygdala when they saw threatening stimuli. Also had lower levels of activity in PFC which may have meant it was harder to inhibit amgydala.

Question 3

Evidence for prefrontal cortex and aggression

Answer 3

Case study- Phineas Gage who suffered accidental damage to his PFL. Went from a quite, sober, nice family man to an aggressive, irritable drunk. Evidences how the PFC may be involved in moderation of our aggressive or violent behaviour.

CAT scan- Grafman et al- studied veterans in the Vietnam war. Found that veterans with structural damage to PFC were more aggressive than those with structural damage to other areas

Raine et al- studied 41 violent murderers pleading NGRI and found that they had brain dysfunction previously implicated in violent behaviour such as the amygdala and PFC.

Question 4

Evidence for neurotransmitters and aggression

Answer 4

Clinical drug studies- role of serotonin in aggression. In clinical studies, antidepressants which raise serotonin levels, SSRIs, also tended to reduce irritability and reactive aggression.

Ferrari et al- studied the link between neurotransmitters and aggression in rats. Allowed rats to fight at the same time everyday by introducing an intruder rat. On the 11th day they did not introduce an intruder rat and measured levels of seratonin and dopamine in the brain. They found that as the rats were anticipating a fight, they had lower levels of seratonin in the brain.

Question 5

evidence for testosterone and aggression

Answer 5

Wagner et al- observed aggression levels in Mice and noticed that after castration aggression levels dropped. When the castrated mice were reinjected with testosterone their aggression levels gradually rose back up to pre castration levels. This provides evidence for how testosterone causes aggression.

Dabbs et al- measured the aggression levels of 89 male prisoners who had committed violent and non violent crimes. Found that VIOLENT prisoners tended to have higher testosterone levels than non violent prisoners

Question 6

Gender differences in aggression levels

Answer 6

Maccoby and Jacklin 1974- undertook many different lab experiments and field experiments in different social classes and various cultures which concluded than boys are consistently more aggressive than girls.

Issue and debate- (gender) research perpetuates differences between men and women. Research may support or perpetuate gender stereotypes that are oversimplified or exaggerated. Women are also capable of committing violent crimes.

Question 7

Gottesman and Shields twin study APRC

Answer 7

Aimed to distinguish whether schizophrenia had a biological basis. They identified 57 schizophrenic patients that were members of a twin pair and tracked down the other twin. The twins were split into 4 categories (both twins were diagnosed, cotwin was diagnosed with a similar disorder, cotwin was diagnosed with a disorder not similar to schizophrenia and while proband had schizophrenia cotwin was healthy)

Results: concordance rates were higher in females than males. Concordance rates for severe schizophrenia was 75% for MZ twibut only 24% for DZ twins.

Conclusions: suggest schizophrenia does have a biological genetic basis and is influenced by a persons genes. However, the concordnace rate for MZ schizophrenia was not 100% so it may suggest social factors may have an effect

Question 8

Ludeke et al APRC

Answer 8

Aim: to determine if peoples personalities could be influenced by their genes. The researchers looked at traditionalism, authoritarianism and religiousness by examining the attitudes of MZ and DZ twins separated at birth.

Procedure: Researchers studied 66 MZ twins and 56 DZ twins separated at birth and reunited. Ps were members of the Minnesota Study of Twins Reared apart group. They filled in various self report measures.
Results: strong correlations were found across all in MZ twins while only conservatism scored strongly for DZ twins.
Conclusions:
Genes do not have an influence on peoples attitudes towards traditionalism.

Question 9

Cortisol and aggression explanation and evidence

Answer 9

Low cortisol levels appear to be linked with high levels of aggression.
Barzman et al- found that low levels of cortisol in the saliva were linked to a higher number of aggresive incidents in psychiatric patients.

Question 10

Wilson and Daly- evolution and aggression

Answer 10

Proposed that status competition is a way of explaining the evolutionary advantage of male aggression. Men will compete in risky activities such as violence to attract females, gain higher status and increase chances of successfully reproducing.

Question 11

evidence for catharsis (freud)- Megargee and Mendelsohn

Answer 11

Aimed to see if there was a link between aggression and personality types. People that were interviewed were given personality tests. They found that these criminals had repressed their anger so much that it had just exploded. They concluded that if people do not let their aggression out in small amounts they will be unable to control it.

Question 12

evidence against catharsis (freud)- Bushman et al

Answer 12

In his study of Catharsis in aggression found that p’s who had engaged in catharsis by venting their anger and aggression were actually more aggressive than those who did nothing

Question 13

describe the process of synaptic transmission (3)

Answer 13

An electrical impulse travels along the pre-synaptic neuron (1). The impulse reaches the synaptic vesicles to
release a neurotransmitter (1). These diffuse across the synaptic gap and attach receptors (1)

Question 14

how does cocaine work?

Answer 14

Cocaine works by blocking the transporter receptors on the presynaptic dopamine neurons in the Ventral Tegmental Area (VTA). As a result the pre-synaptic neurons do not re-uptake dopamine, therefore dopamine remains in the synaptic cleft for longer. This prolongs and intensifies the stimulation of the post-synaptic neuron. Because the VTA activates the nucleus accumbens, the user experiences euphoria

Question 15

Explain how FMRI works

Answer 15

Looks at neural activity in the brain. FMRI detects the rate at which oxyhaemoglobin becomes deoxyhaemoglobin using BOLD contrast imaging. If an area has a high BOLD contrast imaging then it can be inferred that this area of the brain is used in the behaviour observed. The MRI scanner produces a strong magnetic around the participant. This causes molecules in the magnetic field to move in a slightly different way and release radio-waves which the scanner can then detect.
For example, Caccoro used FMRI to look at activity levels of the amygdala in people with intermittent explosive disorder.

Question 16

CAT scans function

Answer 16

show a dimensional image of the structure of the brain and detect any structure abnormalities. It works by passing multiple X rays around the head from different angles to gather more information. For example, Grafman used PET scans to study veterans who fought in the Vietnam war. Found that those with damage to the PFC were more aggressive than those with no brain damage or damage to other areas of the brain.

Question 17

PET scan function

Answer 17

PET scans show areas of the brain that are activated whilst performing specific tasks. They use glucose tracing. Radioactive material is injected into the participant which bonds to glucose in the blood stream, glucose accumulates in areas which are metabolically active which leads the tracer to emit positrons which give out gamma rays that can be picked up by the scanner. A PET scan image will display different levels of positrons according to brightness and colour. For example, Raine used PET scans to look at differences in the brain between 41 participants pleading NGRI in comparison to controls.

In addition, due to PET scans speech has been related to the brochas area.

Question 18

what is the role of the hypothalamus?

Answer 18

The role of the hypothalamus is to maintain homeostasis. It keeps the body in balance by regulating physical experiences like hunger thirst and temperature. It also regulates our behavioural responses to things like pain, threats and sexual satisfaction. It does this by controlling hormonal levels in the body. This includes testosterone, which has been linked to aggressive behaviour

Question 19

what is the role of the amygdala?

Answer 19

The amygdala is a small almond-like structure deep in the limbic system. It enables our instinctive reactions to the environment with emotions such as happiness, anxiety and anger. It connects to the pre-frontal cortex and it is this connection that may lead to the expression of aggression. When we are exposed to threatening stimuli, our amygdala is activated and results in increased emotional arousal. As a result we either take flight (run away) or we fight and become aggressive towards the threat.

Question 20

what is the role of the PFC?

Answer 20

It has various ‘executive functions’ including planning, problem solving, social judgement, decision making and the regulation of emotional responses. Regulating aggression: The prefrontal cortex appears to allow us to control reactive aggressive impulses that stem from the amygdala.This mechanism inhibits us from automatically reacting to threats and allows us to think about an appropriate course of action.

When we do stop and think, we can still decide to act aggressively. We will tend to do this if we have a particular goal in mind. For example, a boxer can remain very calm and pick his or her right moment to throw a punch. This is still an aggressive act, but it has a great amount of control. This type of aggression is referred to as reactive aggression

Question 21

how is serotonin involved in aggression?

Answer 21

low levels of the neurotransmitter serotonin have been found to be associated with an increased tendency towards impulsive and reactive aggressive behaviour.

The serotonin pathways of the brain are extensive and pass through the prefrontal cortex. Biological models of aggression that focus on neurotransmitters suggest that low levels of serotonin in the prefrontal cortex part of the serotonin pathway results in this region no longer inhibiting the fight/flight response of the amygdala, and thus increasing the likelihood of reactive, impulsive aggression.

Under normal circumstances, serotonin works in the brain to inhibit the firing of the amygdala, so if there are low levels of serotonin in the brain, the amygdala will be more active when stimulated by external events, causing the person to act on their impulses and making aggression more likely.

Question 22

testosterone and aggression Dabbs et al

Answer 22

measured testosterone levels in the saliva of 89 male prisoners, some of whom had been involved in violent crime and some in non-violent crime. They found that the more violent prisoners tended to have high levels of testosterone whereas the non- violent prisoners tended to have lower levels of testosterone. In addition, those with high levels of testosterone were rated by their peers as ‘tough’.

Dabbs et al, (1995) also found that testosterone levels are higher in both male and female prisoners who have been convicted of violent crimes, compared with prisoners who have been convicted of non-violent offences

Question 23

evidence in support of status competition- Wilson and Daly

Answer 23

Analysed data from police homicide records in Detroit during1972. Age and sex of perpetrators and victims were analysed. The data were also categorised into various type of homicidal crimes. The results showed that far more homicides were committed by young, unmarried males than any other group. Most victims of homicides were also young, unmarried males. Most homicides seemed to involve conflict caused by retaliation, showing off and jealousy. Wilson and Daly concluded that these results could be explained by status competition. Therefore, they claim that their findings support an evolutionary explanation for higher levels of violence /aggression in males than females.

Question 24

what is the key question in biological psychology?

Answer 24

Can the use of animals in psychological research be justified?

Question 25

Kilkenny 2009- key question

Answer 25

In an analysis of UK and US studies found that only 59% of these studies mentioned how many animals they had used.

Question 26

when did the House of Lords pledge to the 3 R’s?

Answer 26

2002

Question 27

describe an action potential?

Answer 27

The action potential refers to the method by which nerve impulses pass down the axon of the neuron to stimulate a release of a neurotransmitter.

When a neuron receives a message from another neuron this message can either stimulate a excitatory postsynaptic potential reducing its charge or an inhibitory postsynaptic potential which the neuron has received enough excitatory messages an action potential is triggered.

Question 28

Buss- sexual jealously resulting from evolution and natural selection

Answer 28

David Buss (1988) identified two mate retention strategies used by males to control their partners: direct guarding of the female ; negative inducements to prevent her straying

Question 29

evaluation for synaptic transmission as an explanation of how messages move around the brain- evidence for PET scans use

Answer 29

studies using PET scans have found differences in the synaptic receptor sites related to the serotonin pathways in women with pre-menstrual dysphoric disorder (PMDD)- suggesting that correct synaptic transmission of serotonin is important in the brain.