brain structure

Question 1

limbic system

Answer 1

• collection of structured deep inside the brain

Question 2

what behaviors is the limbic system linked to

Answer 2

aggression

Question 3

amygdala

Answer 3

plays a central role in how an organism asses and responds to environmental threats and challenges

it is an important predictor of aggressive behavior

Question 5

what research did Emi cocarro et al do to support the function of the amygdala

Answer 5

• studied people with intermittent explosive disorder
• patients were fMRI scanned while they viewed pictures of angry faces

Question 6

what is intermittent explosive disorder

Answer 6

involves outbursts of extreme reactive aggression

Question 7

results emi cocarro et al

Answer 7

• patients showed high levels and of amygdala activity when viewing the faces
  -this wasn’t a response in non IED patients

Question 8

why did IED patients respond to the angry faces this way

Answer 8

• aggression and amygdala activity is linked
• an angry face is an ecologically valid sign of a threat

Question 9

what part of the brain determines aggression

Answer 9

orbitofrontal cortex (OFC)
located in prefrontal cortex

Question 10

where is OFC

Answer 10

region of pre frontal cortex
above eye sockets

Question 11

what does OFC do

Answer 11

• play an important role in higher cognitive functions such as rational thinking and decision making
• is thought to be involved in self control, impulse regulation and inhibition or aggressive behaviors

Question 12

for patients with a psychiatric disorder which features aggression what activity of the brain is thought to be reduced

Answer 12

• Activity of OFC
• disrupts impulse control

Question 13

what evidence supports function of OFC

Answer 13

raine et al

Question 14

serotonin

Answer 14

• neurotransmitter with widespread inhibitory effects on transmission between neurons in the brain
• slows down neuronal activity

Question 15

what are normal levels of serotonin in OFC associated with

Answer 15

• a reasonable degree of self control

Question 16

what will decreases levels of serotonin in OfC do

Answer 16

• lead to more impulsive behaviors e.g aggression

Question 17

what did Matti Virkkunen do to support serotonin levels with aggressive behaviors

Answer 17

• compared serotonin breakdown product in the cerebrospinal fluid of violent impulsive and non violent impulsive offenders

Question 18

matti virkkunen results

Answer 18

levels of serotonin product breakdown was significantly lower in impulsive offenders

Question 19

dopamine

Answer 19

neurotransmitter they had inhibitory effect in some areas of the brain and excitatory effects in others

Question 20

what is dopamine involved in

Answer 20

regulating motivated behavior and our experience of reward

Question 21

what does dopamines main influence on aggression comes through its interaction with

Answer 21

serotonin

Question 22

donglu seo et al research supporting dopamine and serotonin links in brain

Answer 22

• serotonin interactivity and dopamine over activity are linked with impulsivity and aggression
• serotonin hypofunction is the primary cause of impulse aggression

Question 23

evidence on amygdala = dustin pardini et al

Answer 23

• identified 56 males who had been part of a study when they were 6/7 years old and 20 years later were studied again
• over the 20 yrs these men had consistently behaved aggressively, including criminal violence
• using fMRI scans researchers found a strong negative correlation between aggression levels and amygdala volumes

Question 24

results Dustin Pardini which supports amygdala

Answer 24

• can’t be explained by confounding variables or earlier aggression levels as they were controlled = supporting influence of amygdala

Question 25

correlational research - weakness for links between aggression and brain structure

Answer 25

• a study will find links between high levels of aggression and brain function, dysfunction or structure
• it’s impossible to establish whether are structure is cal cause or effect of aggression

Question 26

how can we overcome the weaknesses of correlational research for brain structure and aggression

Answer 26

• by using drugs to increase serotonin activity
• e.g patients given paroxetine have viewer and less electrical shocks to others
• evidence for a link between aggression and serotonin beyond correlational findings

Question 27

application -
brain structure and aggression

Answer 27

• gives us a better understanding of neural influences on aggression
• serenics is a drug that has been developed to affect the brains serotonin system and decrease aggression with minimal side effects
• useful as human aggression is the root of many personal,
  social and economic costs

Question 28

disadvantage - brain structure = reductionist

Answer 28

• narrow focus on biological factors is reductionist
• amygdala is not an inevitable cause of aggression it also depends on social,psychological and environmental factors
• biological factors isn’t enough to trigger aggression
• reductionist explanation doesn’t reflect the complexity of the causes of aggression

Question 29

conclusion

Answer 29

• there’s food evidence for the role of brain structures such as the amygdala however conclusions from research can be limited as we can’t be certain that these brain structures cause aggression as other factors also contribute towards it
  but
  brain structures contribute to aggression