Agression

Question 1

What are the two neural mechanisms in aggression

Answer 1

1) Limbic system
2) the role of serotonin

Question 2

A01
Explain the limbic system as a neural mechanism in aggression

Answer 2

• links to the brain specifically the amygdala
• key structures of the limbic system: hypothalamus, amygdala, hippocampus and thalamus
• most important: amygdala
• has a key role in human and non human animals in how they respond to environmental threats and challenges
• reactivity of the amygdala in humans is an important predictor of aggressive behaviour

Question 3

A01
Explain the A01 research by Gospic et al on the limbic system as a neural explanation for aggression

Answer 3

• proposed the Ultimatum game
• 2 players asked to divide a given amount of money, confederate decides how money is split, responder accept/rejects offer, if they reject neither of them get any money
• researchers found that when when ppts rejected an unfair reward (seen as social provocation) fast and heightened response in the amygdala was recorded, implicating this region of this brain as involved in aggression
• when a benzodiazepine drug was taken (calm down) there were 2 effects on responses to unfair offers:
  1) halved the number of rejections (reduced aggression)
  2) decreased activity in the amygdala

Question 4

A03
What is a weakness of Gospic’s research on the amygdala associated with aggression

Answer 4

Lab experiment, low ecological validity, aggression may not be displayed in the same ways in real world
- MRI could have confounded the results, ppts brain scans may have been influenced by the unfamiliar situation they are in (low validity)
- researchers equate the perception of unfairness as an operationalised definition of aggression, however are they really the same?

Question 5

A01
Explain the role of serotonin as neural mechanism in aggression

Answer 5

• inhibitory neurotransmitter (reduces post synaptic membrane activity)
• ‘normal’ levels in the orbitofrontal cortex are linked to reduced firing of neuron’s, associated with a greater degree of behaviour control (self control)
• decreased levels reduce self control leading to an increase in impulsive behaviour such as aggression

Question 6

A01
Explain research from Virkkunen et al on the role of serotonin in aggression

Answer 6

• compared levels of a serotonin breakdown product (5-HIAA) in the cerebrospinal fluid of violent impulsive and non impulsive offenders
• the levels were significantly lower in the impulsive offenders (means their serotonin levels were lower)
• they suffered more from sleep irregularities (serotonin regulates sleep patterns), disturbance of this pattern implies a disruption of serotonin functioning, further supporting the role of serotonin in reactive aggression

Question 7

A01
What is the hormonal explanation for agression

Answer 7

Testosterone

Question 8

A01
Explain testosterone as a hormonal explanation for aggression

Answer 8

• male sex hormone and androgen responsible for the development of masculine features
• also has a role of regulating social behaviours via it’s influence on certain areas in the brain implicated in aggression
• high levels of testosterone = aggression

Question 9

A01
Explain research by Dolan at al on testosterone as an hormonal explanation of aggression

Answer 9

• found a positive correlation between testosterone levels and aggressive behaviours
• sample of 60 males (high security prison) who suffered from personality disorders and had history of impulsive violent behaviour

Question 10

A03
What is a weakness of neural explanations of aggression

Answer 10

1) reductionist, specifically the limbic system and role of the amygdala ignores other brain structures
- e.g recent studies suggest the amygdala appears to function in the tandem with the OFC (not part of the limbic system)
- OFC (orbitofrontal cortex) is involved in self control and impulsive regulation linked to aggressive behaviour
- Cocarro et al found that patients with psychiatric disorders that feature aggression, activity in OFC is reduced
- therefore explanation is limited and reduced to only one structure where aggression is far more complex

Question 11

A03
What are strengths of the neural explanation of aggression

Answer 11

1) research support that increased levels of the serotonin reduces aggressive behaviour
- e.g Berman et al found that ppts who were given paroxetine (drug that enhances serotonin activity) they behaved less aggressively compared to a control group whilst playing a video game, delivering fewer and less intense shocks

2) research is correlation, avoiding ethical implications e.g while looking into activity of the amygdala no harm is done to the ppts by possibly damaging the amygdala to discover cause and effect, instead just a Fmri scan
HOWEVER, findings are still inconclusive, we can only see a link between two variables e.g increased amygdala activity and aggressive behaviours, but unclear which variable causes the other, there may be a third variable involved

Question 12

A03
What is a weakness of hormonal explanations (testosterone) of aggression

Answer 12

1) reductionist (limited), there may be other hormones such as the stress hormone cortisol that has an influence on aggressive behaviours
- research has found that when cortisol levels were high, this actually blocks testosterone influences. (Antagonist effect)
- the ‘dual- hormone hypothesis’ supports this, combined activity of testosterone and cortisol may be a better predictor of human aggression than either hormone alone

Question 13

A01
Explains twins as a genetic factor in aggression

Answer 13

• twin studies
• suggest concordance rate for aggression is 50% (DZ twins)
• Coccaro at al collected data from 182 MZ twins, 118 DZ twins and found the concordance rate for physical assault was 50% for MZ twins and 19% for DZ twins
• suggest a genetic component as likelihood id higher for MZ twins

Question 14

A01
Explain adoption studies as a genetic factor in aggression

Answer 14

• attempts to detangle gene/environment interaction
• if we a greater similarity is found between children and their biological parents (rather than between children and their adapted parents) then the role of genetics can be assumed to be a significant factor in determining behaviour
• Rhee and Waldman carried out meta analysis of adoption studies, direct aggression and antisocial behaviour
• found genetic influences accounted for 41% of the variance in aggression
• supports biological explanation for aggression

Question 15

A01
Explain the MAOA gene as a genetic factor for aggression

Answer 15

• MAOA gene codes for the enzyme called monoamine oxidase which regulates the neurotransmitter serotonin
• role is to ‘mop up neurotransmitters’ in the brain after nerve impulse has been transmitted from one neuron to another
• does this by breaking down neurotransmitter especially serotonin into smaller parts to be recycled or excreted (process called catabolism)
• production of MAOA enzyme is determined by the MAOA gene
• dysfunction in this gene may lead to abnormal activity of the enzyme, effecting their serotonin levels in brain where low levels are linked to aggression

Question 16

A03
What are strengths of genetic explanations for aggression

Answer 16

1) Bruner- studied 28 male members of a large Dutch family who were repeatedly involved in impulsively aggressive violent criminal behaviours such as rape, attempted murder and physical assault
- these men had abnormally low levels of MAOA in their brains and the lower-activity version of the MAOA gene

2) Stuart et al- studied 97 men from a treatment programme for domestic abusers, who had inflicted a form of aggression called intimate partner violence
- men with the low activity MAOA gene were found to be the most violent perpetrators of intimate partner violence, engaged in greatest psychological and physical aggression and inflicted the worst injuries on their partners

Question 17

A01
Explain gene environment interaction as a factor of aggression

Answer 17

• low MAOA gene activity linked to aggression only when combined with early trauma
• Frazetto found an association between antisocial aggression and the low activity MAOA gene variant in adult males but only in those who experienced significant trauma (e.g sexual or physical abuse) during the first 15 years of life
• those who hasn’t experienced such trauma were not especially aggressive as adults even if possessed the low activity MAOA gene variant
• therefore the gene doesn’t function in isolation

Question 18

A01
What are the 4 factors in genetic explanations of aggression

Answer 18

1) twin studies
2) adoption studies
3) the MAOA gene
4) gene environment interaction

Question 19

A03
What is a weakness of genetic explanations for aggression

Answer 19

1) reductionist argument, appears they may be more than one gene linked to aggressive behaviour
- Stuart et al studied males involved in IPV (intimate partner violence) and found that the aggression was not linked to low activity MAOA gene variant, but also the 5HHT serotonin gene, therefore genetic explanation may be more complex than we think

Question 20

A01
What does the ethnological explanation of aggression suggest

Answer 20

• the main function of aggression is adaptive as it aids survival e.g anger, hunger, threat and mate competition
• ethology is the study of animal behaviour in natural settings

Question 21

A01
What are the two main adaptive functions of aggression in animal species

Answer 21

1) allows a species to survive as a ‘defeated’ animal is forced to establish territory elsewhere, members of species have to spread over a wider area and discover resources in a different places reducing competition pressure

2) to establish dominance in hierarchies,
- aggression would be naturally selected as it increases reproductive fitness
- male chimpanzees use aggression to climb their troop’s social hierarchy, their dominance gives them special status

Question 22

A01
What is meant by ritualistic aggression

Answer 22

• most aggressive encounters consist of ritualistic signals ( threat displays and appeasement gestures)
• adaptive bc if every aggressive encounter ended with death it could threaten the existence of species

Question 23

A01
What is meant by threat displays as part of ritualistic aggression and give examples

Answer 23

• intend to make an opponent back down + are there last step before an animal either fights or submits and leaves (shows appeasement)
  E.g
• vocalisations
• hooting sounds
• pounding chest

Question 24

A01
What is meant by appeasement gestures

Answer 24

• submission, signalling backing down to a threat display

Question 25

A01 Explain the innate releasing mechanism (IRM) as part of the process of aggression

Answer 25

- physiological process within a species - network of neurons in the brain which responds to threats in the form of aggression - environmental stimulus e.g facial expressions, bearing teeth triggers IRM which ‘releases’ a specific sequence of behaviours - this behavioural sequence is called a fixed action pattern (FAP)

Question 26

A01 What are the 6 features that the FAP can be characterised as

Answer 26

- Lea suggested 6 main features 1) stereotyped: unchanging sequence 2) universal: same behaviour found in every species 3) unaffected by learning (innate): same regardless of experience 4) ballistic: once behaviour triggered, follows inevitable course 5) single purpose: occurs in specific situation and no other 6) responsive: response to a specific stimulus from member of same species

Question 27

A01 Explain research into FAP and IRM’s (stickleback fish)

Answer 27

- during mating season sticklebacks are highly territorial and aggressive (develop a red spot on their underbellies due to mating season) - if another male enters territory, sequence of highly aggressive behaviours are shown (FAP) - the stimulus that triggers the IRM is the sight of red spot - Timbergen found that regardless of shape of wooden model, if it had a red spot the stickleback back would aggressively behave and attack it

Question 28

A03 What is are weaknesses of ethological explanations

Answer 28

1) not entirely generalisable/extrapolate findings: Lorenz and Tinbergen assumed the behaviour they observed in birds and fish must also be typical of humans - should be cautious about making such generalisations, especially to a behaviour (such as warfare) which is extremely complex and outcome may vary due to personality factors and power/authority 2) are FAP’s

Question 29

A03 What are weaknesses of ethnological explanations for aggression

Answer 29

1) not entirely generalisable/extrapolate findings: Lorenz and Tinbergen assumed the behaviour they observed in birds and fish must also be typical of humans - should be cautious about making such generalisations, especially to a behaviour (such as warfare) which is extremely complex and outcome may vary due to personality factors and power/authority 2) are FAP’s really that fixed/changing- aggression/behaviours may actually have more of an environmental influence than was first suggested - ethologists increasingly accept that FAP’s are flexible and the term itself is used less than it once was, replaced by MAPS (modal action patterns), now been found the duration of each ‘aggressive behaviours’ varies from one individual to another - small differences between members of same species, not as fixed as Lorenz suggested

Question 30

A01 How does sexual jealousy differ from males and females

Answer 30

-Females: need a father who will invest resources, time and care, fear he will spend these resources on someone else. Desire certain traits to be passed down onto offspring -Males: fear social infidelity, sexual jealousy is stronger in males due to paternity uncertainty, which may lead to cuckoldry, raising a child who is not his own

Question 31

A01 What have males developed as an adaptive response for sexual jealousy

Answer 31

- males have developed male retentive strategies to minimise risk of infidelity and avoid cuckoldry 1) direct guarding: insisting on knowing where partner is 2) negative inducements: making threats of suicide + physical threats 3) Uxoricide: extreme cases where they kill the wife

Question 32

A01 What did Shackleford find about uxoricide and how it counteracts the evolutionary perspective

Answer 32

- looked at 13,670 cases of uxoricide and found young women were most at risk - defies evolutionary perspective as killing when women is still reproductive and can carry genes - by killing wife he prevents a competitor from reproducing

Question 33

A03 What is are strengths of evolutionary explanations for aggression (sexual jealousy)

Answer 33

1) Research support: studies of abused women found primary cause was extreme jealousy from husband - Wilson interviewed women and those who agreed their partner was ‘jealous and doesn’t want you to talk to other men’ were twice as likely to experience serious violence - supports adaptive trait to ensure partners fidelity - motivated by cuckoldry and wasting time and resources 2) sexual coercion: Camilleri found sexual assault of a female was directly linked with the perceived risk of her infidelity, victims of rape were more likely to have engaged in cheating - rape increases chance of impregnating - real world application of sexual violence/ rape, explains sexual jealousy as a motivating factor

Question 34

A03 What is a weakness of research for sexual jealousy as an evolutionary explanation for aggression

Answer 34

1) methodological issues: studies are correlational meaning there is only a correlation for aggression and male retentive strategies - research may suffer from the ‘third factor problem’ where a third contributor may be present but not studied yet - therefore doesn’t demonstrate cause and effect

Question 35

A01 What are the two evolutionary explanations for aggression

Answer 35

1) sexual jealously 2) bullying/verbal aggression

Question 36

A01 Explain bullying/verbal aggression as an evolutionary explanation of aggression

Answer 36

- bullying can be seen as an adaptive strategy to increase chances of survival and reproduction - for males, dominance and strength may be attractive for females so would be naturally selected - for females, bullying is used to control a partner and secure partner’s fidelity, so they can continue to provide resources for future offspring

Question 37

A03 What is a strength of bullying as an evolutionary explanation for aggression

Answer 37

1) explains gender differences- males more likely to engage in physical violence and aggression, females more likely to engage in verbal aggression - theory accounts aggressive behaviours of both genders and possible reasons for such differences

Question 38

A01 What are the social psychological explanations of aggression

Answer 38

1) frustration aggression hypothesis 2) social learning theory 3) de-individuation

Question 39

A01 Explain the frustration aggression hypothesis as a social psychological explanation for aggression

Answer 39

- Dollard suggested that frustration always leads to aggression, based on the psychodynamic concept of catharsis (release) - suggests frustration is a psychological drive similar to biological drives of hunger and thirst - however drive may not be satisfied as consequences may be too dangerous and source of frustration may not be present, therefore anger is displaced onto a weaker and immediately available target