Aggression - Biological Explanations of Aggression

Question 1

What does MZ and DZ twins stand for?

Answer 1

Monozygotic (identical)

Dizygotic (non-identical)

Question 2

In which type of twin is aggressive behaviour highly correlated?

Answer 2

MZ twins

Question 3

What are the study associated with twin studies of aggression?

Answer 3

McGuffin and Gottesman (1985)

Question 4

What happened in McGuffin and Gottesman (1985)?

Answer 4

Concordance rate of 87% for juvenile aggressive and antisocial behaviour in MZ twins, compared to 72% for DZ twins.

Question 5

What do the results of McGuffin and Gottesman (1985) suggest?

Answer 5

There is a significant genetic contribution to aggressive behaviour.

Question 6

What is the Warrior Gene?

Answer 6

Gene responsible for producing enzyme monoamine oxidase A (MAOA) may be associated with aggressive behaviour (Warrior Gene). MAOA’s job to break down neurotransmitters in brain. When gene not functioning correctly, excess levels of neurotransmitters may lead to aggression.

Question 7

What is the case study associated with the Warrior Gene?

Answer 7

Jim Fallon

Question 8

What happened with Jim Fallon?

Answer 8

Has same brain and genetics of serial killer but not a killer, however lacks empathy.

Question 9

What brain damage do serial killers sometimes have?

Answer 9

Orbital cortex, temporal lobe, amygdala.

Question 10

What are two problems to do with twin studies?

Answer 10

Assume MZ and DZ twins experience the same upbringing, may not as parents/teachers make an effort to differentiate twins depending upon personalities.
Concordance rates are below 100%, means genetic influence is only part of the explanation.

Question 11

What are two studies associated with the influence of genes on aggression?

Answer 11

Lagerspetz (1979)

Brunner et al (1993)

Question 12

What happened in Lagerspetz (1979)?

Answer 12

Bred 25 gens of mice, 2 most aggressive and 2 least aggressive. Lead to one groups being super-aggressive and the other very docile.

Question 13

What do the results of Lagerspetz (1979) show?

Answer 13

There is, at least in animals, a genetic component to aggressive behaviour.

Question 14

What is a positive and negative of animal research in relation to Lagerspetz (1979) study?

Answer 14

Positive - Quality of Research, bred 25 generations of mice, large participant size. Clear variables and ruled out social differences.
Negative - Degree of animal suffering, do not show outward signs of suffering. Being aggressive may reduce chances to mate and pass on their genes.

Question 15

What happened in Brunner et al (1993)?

Answer 15

Family with men having history of violence. Violent men suffer a genetic defect on X chromosome, cripples enzyme regulating aggressive behaviour. Not found in non-violent men of family. Tested urine, found excess levels of neurotransmitters, may have predisposed men to violence.

Question 16

What positive implications does research into aggressive have?

Answer 16

Offender treatment and rehabilitation - Can predict if a person will be aggressive then they can get help or anger management before they murder or hurt people.

Question 17

Why is the role of genes in relation to aggression socially sensitive?

Answer 17

Blames parents for child’s aggressive behaviour, stating 2 aggressive individuals are likely to have an aggressive child.

Question 18

Why is the role of genes in relation to aggression Deterministic?

Answer 18

People still have a moral sense of what is right and wrong, free will. Labelling people as aggressive means they have an excuse for their aggressive behaviour.

Question 19

What are neurotransmitters?

Answer 19

Chemicals that allow impulses to travel between neurons.

Question 20

What neurotransmitters play a part in aggression? High or low levels?

Answer 20

Low levels of serotonin

High levels of dopamine

Question 21

How is serotonin associated with aggression?

Answer 21

Normal levels - calming effect on brain. Low levels - inhibitory effect removed, leading to less control of behaviour.

Question 22

What study is associated with serotonin and aggression?

Answer 22

Mann et al (1990)

Question 23

What happened in Mann et al (1990)?

Answer 23

Gave dexfenfluramine to 35 P’s, depletes serotonin levels, used questionnaires to access hostitli8ty and aggression levels, found hostility and aggression levels to increase in males.

Question 24

Evaluate the study of Mann et al (1990).

Answer 24

Aggression didn’t increase in woman, socially desirable answers, less likely to admit to undesirable behaviour. Questionnaires only gather info P’s are willing to share, may not be same as actual behaviour. Leads to lack of validity in data.

Question 25

How is dopamine associated with aggression?

Answer 25

Increases in dopamine activity = increases in aggressive behaviour.

Question 26

What study is associated with dopamine and aggression?

Answer 26

Ferrari et al (2003)

Question 27

What happened in Ferrari et al (2003)?

Answer 27

Allowed rat to fight for 10 days, on 11th day didn’t allow, found serotonin and dopamine levels increased in anticipation of a fight.

Question 28

What do the results of Ferrari et al (2003) show?

Answer 28

Shows experience of aggression changes the animals brain chemistry.

Question 29

Evaluate the ethics of Ferrari et al (2003) in relation to animals.

Answer 29

Protection through legislation -Strict laws and codes of conduct that protect animals used in research.
Animal rights - Have right by virtue of their ‘inherent value’, includes the right to be respected and not harmed.

Question 30

What hormone is associated with aggressive behaviour?

Answer 30

Testosterone

Question 31

How is testosterone associated with aggressive behaviour?

Answer 31

Males more aggressive than females, may be due to 10 times more testosterone, levels escalate at puberty 15-25, age group most likely to commit violent crimes.

Question 32

What study is associated with testosterone and aggressive behaviour?

Answer 32

Dabbs et al (1995)

Question 33

What happened in Dabbs et al (1995)?

Answer 33

Studied testosterone levels of inmates, those who had committed violent and non-violent crimes. Found higher testosterone levels in more violent crimes.

Question 34

What can be concluded from Dabbs et al (1995)’s results?

Answer 34

Positive correlation between violent crimes and higher levels of testosterone.

Question 35

Evaluate Dabbs et al (1995).

Answer 35

If testosterone were major force behind aggression, we’d expect all females to be docile and men aggressive. Other factors must be involved.

Question 36

Why is correlational research a problem in relation to Dabbs et al (1995)?

Answer 36

Cannot be sure if high testosterone levels are causing or aggression or if aggression is causing high testosterone levels or if another factor is causing both.

Question 37

What are the IDAs relevant to biological causes of aggression?

Answer 37

Nature v Nurture

Socially Sensitive Research

Question 38

Why are biological causes of aggression part of the Nature v Nurture debate?

Answer 38

Brunner et al (1993) shows there is a genetic element to aggression. Significant number of males in the family are aggression. But if the was all due to genetics, we’d expect a;; od the males to have aggression problems.

Question 39

Why are biological causes of aggression socially sensitive?

Answer 39

Could be used to explain away unacceptable behaviour, Mann et al (1990) implies neurotransmitters are the cause of aggressive behaviour. Therefore individuals could justify attacks by claiming that their biology made them do it.