aggression

What's the limbic system responsible for?

What's the limbic system responsible for?

Processing emotional responses an, cortex mediates levels of aggression by moderating testosterone levels

most important part of limbic system

amygdala

what does malfunction in the amygdala lead to (eg. tumour/ atypical development)

being overly sensitive and the individual interprets situations as aggressive when they're not

what does malfunction in the amygdala cause (eg. tumour/ atypical development)

increased testosterone levels making aggression more likely

research into limbic system (1)

Raine scanned 41 murderes brains and 41 controls. Pet scans sound some had abnormalities in limbic system functioning

research into limbic system (2)

Kramer et al, 14 year old girl with tumour in the limbic system. Suffered seizures and aggressive behaviour. Tumour treated with drugs and returned to normal levels of aggression.

What's serotonin?

A neurotransmitter involved with communication of impulses between neurons.

What are normal levels of serotonin linked to

reduced levels of firing neurons and a greater degree of behavioural self control

What are decreased levels of serotonin linked to

increase in impulsive behaviour including aggression

Research into serotonin (1)

Bond, drugs that clinically raise serotonin levels (eg. antidepressants) found to lower levels of irritability and impulsive aggression

Research into serotonin (2)

Virkunnen et al, compared levels of serotonin metabolite in violent impulsive and non-impulsive offenders and found significantly lower in impulsive offenders

What's testosterone?

hormone that's responsible for development of male features and plays role in regulating social behaviour

what do levels of testosterone influence (eg. high)

activity in orbital-frontal cortex, high = heightened emotional aggressive response is likely

Research into testosterone (1)

Dabbs, found that those with high levels of testosterone had history of primarily violent crimes and low levels primarily committed non-violent crimes

Research into testosterone (2)

Dolan et al, found positive correlation between testosterone levels and aggressive behaviours in sample of 60 male offenders in UK maximum security hospitals who had histories of impulsively violent behaviour

Evaluation of the role of neural and hormone mechanisms overview

supporting evidence, evidence mixed, too simplistic, issue with cause and effect

evaluation of neural and hormonal mechanisms strength

A strength for neural and hormonal mechanisms is supporting evidence, Scerbo and Raine carried meta- analysts of 29 studies assessing levels of serotonin in anti-social children. They found that the children have low levels of serotonin, this suggests that a reduction in serotonin results in impulsive behaviour and aggression

evaluation of testosterone, weakness

A weakness of the role of testosterone is that evidence of its role is mixed. Carre & Mehta's dual hormone hypothesis claims high testosterone levels only lead to aggression when cortisol levels are low. This suggests that the combines activity of testosterone and cortisol may be a better predictor of aggression that testosterone itself.

Evaluation of limbic system weakness

A weakness for the limbic system explanation for aggression is that its too simplistic. Coccaro et al showed that the orbital frontal cortex activity is reduced in psychiatric patients that feature aggression. This shows that aggression can't be explained by the limbic system alone - its highly complex.

evaluation of neural and hormonal mechanisms weakness

A further limitation of neural and hormonal mechanisms are issues with cause and effect. Most research is correlational as alternatives are limited. This is because studies with humans would have ethical issues and animal studies raise issues with generalisability. As the research is just correlational, it could actually be that carrying out aggressive acts leads to changing levels of hormones or neurotransmitters rather than the reverse.

what's the genetic explanation of aggressive behaviour based on

the nature argument that aggression runs in families, a specific gene is inherited

what are the two types of studies used to research genetic explanations of aggression

twin studies and adoption studies

what's a twin study for genetic factors

Coccaro et al, 187 MZ adult twin pairs and 118 DZ. Measured physical and verbal aggression. Concordance rate of 50%for MZ and 19% DZ for physical aggression and 28% MZ and 7% DZ for verbal. Shows that more genes shared more similarities of aggression, shows genes have effect.

what's a negative for Coccaro et als twin study

hard to separate effect, MZ could have copied each other

Whats another twin study for genetic explanation

MuGuffin and Gottesman, Mz and DZ twins measured aggressive and antisocial behaviour. 87% for MZ vs. 72% for DZ for aggression and antisocial behaviour

what's a negative for MuGuffin and Gottesmans twin study

Wasn't 100% concordance rate so genetic factors cant be only influence

what's one of the adoption studies for biological explanation

Rhee and Waldman, meta-analysis 51 twin and adoption studies 87000 individuals for aggression and antisocial behaviour. Genetic influences accounted for 41% of aggression

whats a weakness for Rhee and Waldmans adoption study

meta-analysis hard to draw conclusions because they measure aggression differently

what's another adoption study

Hutchings and Mednick, reviewed 14000 adoptions In Denmark, significant positive correlation between number of convictions for violence among biological parents and adopted sons. Shows genes isn't only influential fact, environment plays part.

Whats another possible explanation for aggression amongst adoption studies

Trauma from adoptions

Whats a strength for Hutchngs and Mednicks adoption study

Big sample size, strengthens research

what's the gene called linked to aggressive behaviour

the MAOA gene

what's the MAOA gene responsible for

producing the enzyme Monoamine Oxidase A

what the role of the Monoamine Oxidase A enzyme

regulate levels of serotonin in the brain

what's the warrior gene

a variant of MAOA gene

what does the warrior gene lead to

low levels of MAOA activity linked to low levels of serotonin and in turn aggressive behaviour

Research into the MAOA gene

Brunner studied 28 male members of a dutch family who repeatedly involved with criminal behaviour such as rape, attempted murder and physical assault, found these men had abnormal low levels of MAOA in their brains and lower activity version, this suggests the gene that produces MAOA may be a candidate gene for aggression

Another research into the MAOA gene

Stuart at al, studied 97 men who were part of a 'batterer' treatment programme because they've been involved in inflicting intimate partner violence. Men with low activity MAOA gene found to be most violent perpetrators.

What are the evaluations of the genetic explanation - overview

support from prosocial behaviour, support from animal studies, conc not 100%, multiple genetic influences

strength to the MAOA explanation

A strength of the MAOA explanation is support from prosocial behaviour. Matins et al found that ps with high activity MAOA were more co-operative and less aggressive than those with low activity MAOA. This finding confirms the importance of the MAOA gene in aggressive behaviour.

another strength of the MAOA explanation

Another strength of the MAOA explanation is support from animal studies, when genetic deletion techniques allow research to 'knock out' single genes in mice. Godar et al found that MAOA know out mice had significantly high serotonin levels and were more aggressive. When serotonin blocked by drug fluoxetine, mice reverted to non-aggressive again. These findings show MAOA must normally have some function in relation to serotonin, keeping it at a 'normal' level.

Limitation to genetic explanation

Limitations with some of the supporting research studies. For example, concordance rates for twin studies aren't 100% - this suggests that there must be other factors involved. Eg environmental effects. With adoption studies its difficult to know if genetic factors have resulted in higher aggression levels in the adoptees, or whether these high levels of aggression are down to the trauma of adoption

another limitation to the genetic explanation

another issue that there are probably multiple genetic influences - the sizes of genetic effects are statistically significant but quite small. This means there are probably other genes involved in aggression. Research by Vassos et al in meta-analysis shouldn't find any association between a single gene and aggression. This suggests that its likely that several genes interact in a complex way to determine aggressive behaviour and that there's unlike to be a single candidate gene for aggression.

What do ethological explanations of aggression aim to do

understand innate behaviour of animals by studying them in their natural environments and assume the aggression is adaptive for the survival of their species

whats the evidence of the ethological explanation in the animal kingdom

the 'defeated' animal is rarely killed but is forced to establish territory elsewhere. This means that members of the species will spread elsewhere and find new resources and mates (reducing competition)

whats an innate releasing mechanism

a biological process or structure which is activated by an external stimulus that triggers a fixed sequence of behaviours (FAP)

Whats a fixed action pattern

a sequence of behaviours that occurs throughout the species

what are the 6 features of a FAP

stereotypes, universal, unaffected b learning or individual experiences, ballistic, single purpose, occurs in response to a specific stimulus or signal

state Tinbergens research into ethological explanation

Tinbergen observed that male sticklebacks are highly territorial during mating season when they also develop a red spot on their underbelly. If a male enters with a red underbelly IRM and FAP take place. He presented a series of wooden models of different shapes and found that regardless of the shape if the model had a red spot the stickleback would be aggressive.

What are the 4 evaluations for the ethological explanation of aggression

Supporting evidence, cultural differences, against ritualistic aggression, evidence suggesting FAPs aren't fixed

Strength for ethological explanation

A strength of the ethological explanation is that a it has supporting evidence. Tinbergen supports the existence of IRM and FAP though his study of the male stickleback. this adds to the validity of the explanation as it demonstrates the genetic and physiological basis to aggression.

Limitation of ethological explanation (1)

One limitation is that there's cultural differences in aggressive behaviour. Nisbett at al found there was a north-south divide in homocide rates in the USA. When white males from southern US were insulted in a research situation they're were more likely to become aggressive that northern white males. He concluded aggressive behaviour was a 'learned social norm' against white males in the southern sates. This contradicts ethological theory as its difficult to explain how cultural differences can override innate influences.

Another limitation to ethological explanation (2)

Another limitation is that there's evidence against ritualistic aggression. Goodall studied chimpanzees in Tanzania and found that they continued to behave aggressively even if the victims were showing appeasement signals and were defenceless. This therefore challenges the ethological theories assumption that aggression has evolved into a self-limiting and relatively physical harmless rituals

Another weakness to the ethological explanation (3)

Theres evidence to suggest that FAPs aren't fixed. Hunt argued that they're influenced by environmental factors and learning experiences and are therefore in fact quite flexible. Some ethologists now prefer to use the term 'modal action pattern'.

what are evolutionary explanations of aggression based on

the animal kingdom and then applied to humans

what do evolutionary explanations of aggression claim humans have

an innate drive to pass on their genes

why is aggression seen as an adaptive behaviour

because its a trait which increases the chances of passing on genes which would be continued via natural selection

what are the 2 parts of the evolutionary explanation which demonstrate behaviours an individual shows that increases the chances of keeping a mate so their genes survive

sexual jealousy and bullying

whats infidelity

occurs when one partner seeks out another mate with whom to reproduce

why is infidelity evolutionary advantageous for males

increases chance of his genes being passed onto successive generations

why is infidelity evolutionary advantageous for females

ensures 'fittest' sperm fertilises the egg

what are the 2 types of sexual jealousy

direct guarding and negative inducements

whats direct guarding

involves behaviours which restrict access of other males (eg checking phone/ turning up unexpectedly)

whats negative inducement

use of verbal threats or direct violence which induce fear

why does female sexual jealousy occur

due to female ancestors needing a mate to provide for her and her offspring - sexual jealousy reduced the change of the male leaving to be with another partner

Whats one piece of research that shows that jealousy leads to aggressive behaviour

Wilson, found women who reported male retention strategies in partners were twice as likely to have suffered physical violence from their partners. 73% required medical attention and 53% feared for their lives.

whats another piece of research that shows that jealousy leads to aggressive behaviour

Shackleford, survey 461 males and 560 females in long term relationships about mate retention strategies. Found positive correlation between mens reports of their mate retention strategies and women reports of their partners physical violence. This also suggests sexual jealousy leads to aggressive behaviour

whats bullying

where a more powerful individual attacks a weaker person deliberately and repeatedly

why is bullying adaptive according to the evolutionary theory

promoting their own health and creating reproductive opportunities.

why did Volk suggest bullying was attractive to the other sex

in males it suggests dominance, resources and strength. In females tends to occur within relationships and involves controlling a partner, secures partners fidelity so continue to provide for offspring

whats the evaluations for the evolutionary explanation

gender differences, useful practical application, doesn't explain cultural differences

whats a strength for the evolutionary explanation

A strength for the evolutionary explanation is that they're able to explain gender differences in behaviour. Males engage more in aggression than females. Campbell argues aggression in females risks survival of their offspring so they use other more adaptive strategies eg. verbal aggression to retain a partner who provides resources. This ability to explain such gender differences increases the validity of the explanation.

A further strength to the evolutionary explanation

A further strength to the evolutionary explanation is the useful application. For example Clares Law gives any member of the public the right to ask the police if their partner may pose a risk to them. AN evolutionary understanding of bullying can help us devise effective anti-bullying interventions to increase the cost of bullying. Rigby found that most anti-bullying programmes fail because they fail to recognise the evolutionary assumption that bullying occurs for the individual to gain dominance

On limitation of the evolutionary explanation

one limitation is that evolutionary theory doesn't explain cultural differences in aggression eg. the Kung San people of the Kalahari discourage aggression and anyone who's aggressive loses status, whereas the Yanomamo in Venezuela use aggression to gain status in society. This suggests aggression isn't universal as evolutionary theory would suggest.

Who came u with frustration-aggression hypothesis

Dollard et al

what approach is the frustration-aggression hypothesis based on

psychodynamic

whats catharsis

process of realising pent up anger

explain the process of how frustration leads to aggression

goals blocked by external forces, frustration is experienced, an aggressive drive to release this pent up energy is experienced and then anger, hostility or violence is experienced

when is aggression more likely (in terms of frustration aggression hypothesis)

if individual is close to achieving their goal

what are 3 reasons aggression can't be directly expressed towards the source of frustration

the source may be abstract, more powerful or unavailable

what happens to the expression of aggression when the source is unavailable

aggression is displaced onto another viable source

Research that supports claim that all types of frustration leads to aggression

Buss, examined whether different types of frustration would affect the likely hood of aggression occurring (eg. falling to win money, failure on a task or failure to get expected grade), found all types of frustration led to aggression, compared to control group

Another piece of research which supports that frustration leads to aggression

Geen, male students task of completing jigsaw puzzle. Group 1 impossible puzzle, Group 2 ran out of time because one person kept interfering, 3 insulted at every mistake. Then another study where they have to give electric shocks to confederate. 3 gave strongest shocks then 2 and 1. All 3 stronger than control group

what's the 'weapons effect' in terms of aggression

shows that cues make aggression more likely

first piece of research which demonstrate the 'weapons effects' in terms of aggression

Berkowitz and Le Parge (1967) found if students became frustrated in lab test, they were more likely to give electric shocks when there's a weapon next to them. Shows that frustration only created readiness for for aggression, aggressive cues in environment make more likely it will occur.

second piece of research which demonstrate the 'weapons effects' in terms of aggression

Berkowitz (1989) created anger and frustration in ps by giving shocks. Ps then had opportunity to give shocks back. Berkowitz found that number of shocks given was dependent on presence of weapons in lab - when 2 guns present on table next to machine average number of shocks was 6.07 whereas no guns was 4.67

One strength of the frustration-aggression hypothesis

One strength of the frustration-aggression hypothesis is that Berkowitz's findings have practical application in real life, eg. the gun control debate in USA. Some states allow 'open carry', where a gun doesn't have to be concealed, but the presence of a gun may act as a cue, making aggression more likely to occur. Therefore research into 'weapons effect; could be used to try to reduce gun-related violence by showing that aggressive cues should be removed from the environment

One weakness of frustration-aggression hypothesis

One limitation for the frustration-aggression hypothesis is that there's evidence to support that aggression isn't always cathartic. Bushman found ps who vented their anger by repeatedly hitting a punch bag became more angry and aggressive rather than less. This questions the validity of the hypothesis.

Second limitation for the frustration-aggression hypothesis

Another limitation is that Berkowitz later argues that aggression is triggered by many stimuli eg. jealousy and not just frustration. Also the outcome of frustration can be a variety of responses, not just aggression eg. despair. Hypothesis can only explain how aggression arises in some circumstances.

How did Bandura claim that aggression can be learnt

directly through operant conditioning, but recognised aggression cant always be explained by such direct mechanisms

What are the 2 forms of indirect social learning mechanisms in which to learn aggressive behaviour

observational learning and vicarious reinforcement

outline 4 meditational processes needed for observational learning to take place

attention (observer must notice RM behaviour), retention (observer must be able to remember RM aggression behaviour, forming a mental representation of how behaviours carried out), reproduction (observer must be able to replicate/repeat behaviour), motivation (observer needs to have a reason to imitate the behaviour - only if some kind of reward

What is self-efficacy in relation to whether an aggressive behaviour is likely to be imitated

refers to the extent to which the individual is confident to replicate the behaviour and whether the individual believes the action will achieve the required goal

whats one piece of research which demonstrates SLT in terms of aggression

Bandura et al, studied 4 year old children, 36 boys and 36 girls. Either watched aggressive model/non-aggressive model. Then frustrated by being shown toys they couldn't play with. Found that aggressive model children reproduced much of aggression. Children in non-ag exhibited no aggression. More likely if model is the same gender.

whats another piece of research which demonstrates SLT in terms of aggression

1- children watch adult kick and punch Bobo doll, 2- children watch some aggression behaviours and adults rewarded with sweets, 3- same a.b. but adult is punished. Found children most likely to imitate aggressive behaviour if they observed adits being rewarded for it. This supports concept of vicarious reinforcement.

One strength of the SLT explanation

One strength of the SLT explanation is the application in helping to reduce aggressive behaviour. If people are learning to be aggressive as a result of viewing aggressive models then if aggressive models are removed and replaced with prosocial models then their aggressive behaviour should be reduced. This would be very beneficial to society and could stop lots of harmful and aggressive behaviour

Another strength of the SLT explanation

Another strength of the SLT explanation is its helpful in understanding cultural differences. People in different cultures have different role models. Eg. In high aggression gang cultures young men looking up to powerful aggressive gang leaders and imitating them to gain the same respect (can also be seen opposite way with Amish). This means the SLT explanation of aggression has an advantage over the biological explanation as the cant account for cultural variations in agg behaviour

One weakness for the SLT explanation

One weakness for the SLT explanation is that it only looks at learning in the acquisition of aggression. This overlooks the role of biology. research consistently shows links with high testosterone and aggression. Therefore its more likely both biology and learning have a role to play in aggression. SLT on its own is too reductionistic

Define term de-individuation

reduced sense of personal identity and responsibility

who made the term de-individuation and what were they trying to explain

Le Bon, to explain behaviours of crowds