3.1.3 the brain and aggression

Question 1

How is the brain separated?

Answer 1

-2 halves called hemispheres
-both sides share many of the same features (bilateral)

Question 2

What is the process of looking at the hemispheres separately?

Answer 2

lateralisation

Question 3

How are the hemispheres joined?

Answer 3

joined by corpus collosum which passes info between the 2 halves

Question 4

How do the different genders use the hemispheres?

Answer 4

Women use both halves more, men are more right brain dominant

Question 5

What are lobes?

Answer 5

regions of the brain which give generalised areas for behaviour

Question 6

How many lobes?

Answer 6

6

Question 7

What are the 6 lobes called?

Answer 7

frontal lobe, parietal lobe, occipital lobe, temporal lobe, cerebellum, brain stem

Question 8

What is the role of the frontal lobe?

Answer 8

controls behaviour and emotions

Question 9

What is the role of the parietal lobe?

Answer 9

perception, spelling and numbers

Question 10

What is the role of the occipital lobe?

Answer 10

vision, colour and identification

Question 11

What is the role of the temporal lobe?

Answer 11

language, facial recognition, hearing and speech

Question 12

What kind of behaviours is the limbic system involved in?

Answer 12

emotional and motivational behaviours

Question 13

What is the limbic system made up of?

Answer 13

hypothalamus, pituitary gland, amygdala, hippocampus

Question 14

What does the hypothalamus do?

Answer 14

-acts as body’s smart control coordinating centre
-carries out homeostasis
-influences emotional and motivational behaviour
-link between NTs and hormones

Question 15

Link between hypothalamus and aggression

Answer 15

-warped amount of hormones released (eg too much testosterone or not enough serotonin/dopamine

Question 16

Evidence for hypothalamus and aggression

Answer 16

-Alpers studied a well mannered lawyer who suffered a tumour in the medial hypothalamus and began to display aggressive outbursts

Question 17

What does the pituitary gland do?

Answer 17

-acts as body’s master gland and controls other glands
-releases hormones

Question 18

What does the amygdala do?

Answer 18

-important in survival as it processes fearful and threatening stimuli
-range of behaviours such as sex and aggression
-emotional centre
-links emotions to memories. perceives emotions

Question 19

How does the amygdala link to aggression?

Answer 19

-when damaged, emotions can’t be processed properly which can lead to intense responses
-left side controls fight/flight
-right side controls emotional memory
-could malfunction and cause drastic emotions eg, due to tumor

Question 20

Evidence for the amygdala and aggression

Answer 20

-Raine discovered murderers had lower glucose metabolism in left amygdala and greater in right
-animal experiments showed lesions to amygdala could abolish aggression eg Downer cut part of amygdala in monkeys and visual signals caused no response as ther was no amygdala to reach

Question 21

What does the hippocampus do?

Answer 21

-vital role in learning and memory
-involved in forming LTMs and making them resistant to forgetting

Question 22

Link between hippocampus and aggression

Answer 22

-damage means can’t form LTMs and remember consequences of behaviour which causes recidivism

Question 23

Evidence for hippocampus and aggression

Answer 23

-Chang and Gean found that stress in socially isolated mice activates their hippocampus neurons which induces aggression]#

Question 24

What does the prefontal cortex do?

Answer 24

-role in personality
-role in decision making and self restraint
-control over social inhibitions
-problem solving and planning

Question 25

Where is the prefontal cortex?

Answer 25

in frontal lobe

Question 26

How does the prefontal cortex link to aggression?

Answer 26

-controls personality so can make people violent/unlikeable
-when damaged, emotions can’t be processed and behaviour becomes intense
-when underactive, impulses can’t be inhibited

Question 27

Evidence for prefontal cortex and aggression

Answer 27

-Phineas Gage had damaged prefontal cortex and underwent major personality change
-Raine found murderers had lower glucose levels in PFC, making them impulsive and lacking self control

Question 28

How might serotonin explain aggression?

Answer 28

-neurotransmitter that inhibits aggressive social response by preventing stimulation of amygdala
-low levels means there’s less inhibition of amygdala stimulation, so it is easily activated by external events and causes impulsivity

Question 29

Evidence to support serotonin influencing aggressive behaviour

Answer 29

Mann et al gave ppts drug ‘dexfenfluramine’ to lower serotonin levels, ppts given questionnaire to measure aggression levels which were increased
-only gave drug to men which introduces gender bias

Question 30

How might dopamine explain aggression?

Answer 30

appears to be a link between dopamine and increased levels of aggressive behaviour

Question 31

Evidence to support dopamine influencing aggressive behaviour

Answer 31

-Lavine used amphetamines to increase dopamine levels and found an increase in aggression
-antipsychotic drugs used to reduce dopamine and therefore aggression
-HOWEVER this is reductionist and is insufficient to explain complex behaviour