Aggression

Question 1

what are the neural mechanisms in aggression?

Answer 1

the limbic system and serotonin

Question 2

what is the limbic system?

Answer 2

connects the brain stem and the cortex

has the amygdala

controls a range of emotional behaviours

Question 3

what is the role of the amygdala?

Answer 3

quickly evaluates the emotional importance of sensory information and promoting an appropriate response

Question 4

what did Pardini et al find

Answer 4

participants with smaller amygdalas showed higher levels of aggression

Question 5

what did ervin study and find?

Answer 5

case study of female patient

electrically stimulated her amygdala

she became very angry and flung herself at a wall

atypical female

Question 6

what is kluver and bucy find?

Answer 6

that destroying the amygdala in aggressive monkeys, resulted in less aggressive behaviour

Question 7

what study was done using fmri scans on the limbic system?

Answer 7

ps had their brains scanned while playing a game where they could reject or accept an offer of money. heightened activity in the amygdala when they rejected money because they thought it was unfair

Question 8

What also operates with the amygdala?

Answer 8

the orbitofrontal cortex

Question 9

what does the orbiofrontal cortex do?

Answer 9

regulates emotional responses driven by the amygdala

damage results impulsivity and loss of control

Question 10

What did Raine et al find?

Answer 10

investigated brain activity in 42 murderers using PET scans.

abnormal activity in the amygdala and reduced glucose metabolism in the orbitofrontal cortex

Question 11

What is serotonin?

Answer 11

a neurotransmitter involved in the communication of impulses between neurons

Question 12

What are normal levels of serotonin associated with?

Answer 12

greater behavioural control and it typically inhibits the firing of the amygdala system

Question 13

what are low levels of serotonin associated with?

Answer 13

low behavioural control, impulsivity and aggression

Question 14

what is tryptophan?

Answer 14

increases serotonin levels in the brain

Question 15

What did Rayleigh study and find?

Answer 15

gave different diets to monkeys

the monkeys who diet was high in tryptophan showed decreased levels of aggression

Question 16

what did Passamonti find and study?

Answer 16

manipulated tryptophan levels in participants diets

ps given questionnaire to asses their aggressive tendencies

fmri scans to measure reaction to facial expressions

on low serotonin days, communication was weaker

Question 17

practical application of research into serotonin

Answer 17

diets to easier serotonin levels such as tryptophan could be given to juvenile delinquents in order to calm aggressive tendencies

Question 18

How have high levels of serotonin been associated with aggression?

Answer 18

dukes et al found a relationship

Question 19

What is testosterone?

Answer 19

an androgen secreted by the testes.

Question 20

Testosterone

Research for (mice)

Answer 20

Wagner- catstrated mice and aggression reduced, later injected them with testosterone which re-established their aggression.

Question 21

Testosterone

Research for (species)

Answer 21

Increasing testosterone caused greater aggressive behaviour in several species and reducing it had the opposite effect.

Question 22

Testosterone

Research for (prisoners)

Answer 22

Dabbs- measured testosterone levels in 692 adult male prisoners, higher levels were found in violent offedners compared to non-violent offenders.

Found a similar effect in women prisoners.

Question 23

Testosterone

Research against (Dual-hormone hypothesis)

Answer 23

high levels of testosterone lead to aggresive behaviour when cortisol levels are low.

Question 24

Evaluation of testosterone

Aggression or dominance?

Answer 24

Studies show that testosterone doesnt necessarily increase aggression but increases status-seeking behaviour, which is not intended to cause harm.

Question 25

What does genetic theory say about aggression?

Answer 25

that genes are the cuase of aggressive behaviour.

Question 26

Genetic factors Research for (mice)

Answer 26

Lab selective breeding study. Isolated a group of mice in order to identify mice more prone to aggression. interbred the aggressive mice, after 19 generations, rates of aggression were 10x higher than in the controls. the aggressive mice had heavier testes and forebrains and altered levels of serotonin and noradrenaline.

Question 27

Genetic factors Research for (twin and adoption studies)

Answer 27

Coccaro used a questionnaire to measure hostility in male participants. they found concordance rate of 50% for MZ twins and 19% for DZ twins. Rhee and Waldman- meta-analysis of adoption studies, found genetic influences account for 41% of the variation of aggression.

Question 28

Genetic factors The MAOA Gene

Answer 28

This gene is responsible for regulating the enzyme MAOA, which breaks down the neurotransmitters serotonin, noradrenaline and dopamine. This allows neurons to commincate more effectively.

Question 29

Genetic factors What does reserch suggest about the MAOA Gene

Answer 29

that the MAOA-L version predisposes a peron to violence.

Question 30

Genetic Factors What did Brunner research?(Dutch family)

Answer 30

Male members of this family had been particulary aggressive, the males were found to have the rare mutated version of the MAOA gene.

Question 31

Genetic factors Research for the MAOA gene (chilli sauce)

Answer 31

Mcdermott- those with the MAOA-L gene were more likely to force someone to eat chilli sauce, than someone with the MAOA-H gene.

Question 32

Genetic factors Research for the MAOA gene (Finland)

Answer 32

Studies prisoners in Finland, found severly violent prisoners had the MAOA-L gene in comination with the CDH13 gene.

Question 33

Genetic factors Rearch for MAOA gene (childhood influences)

Answer 33

Capsi studied 500 male children and looked at their anti-socail behaviour and found that the MAOA-L gene was invloved in aggression, but only if they had been maltreated as children. suggestes an interactionist approach.

Question 34

Genetic factors The warrior gene

Answer 34

Research found that the MAOA-L gene is much more frequent in New Zealand Maori populations with a history of warfare than western populations. Socially sensitive.