Neural Mechanisms

Question 1

proactive aggression

Answer 1

• a planned method of getting what you want
• response in anticipation of reward

Question 2

reactive aggression

Answer 2

• response to perceived threat
• angry + impulsive
• accompanied by physiological arousal

Question 3

biological approach to explain aggression

Answer 3

• neural explanation
• hormonal explanation
• genetic explanation

Question 4

neural mechanisms

Answer 4

• structures e.g. neurones, neural circuits, regions of the brain
• also hormones + neurotransmitters
  = regulate aggression e.g. through the limbic system, serotonin, testosterone

Question 5

the limbic system - neural mechanisms

Answer 5

• involves structures e.g. amygdala, hypothalamus, hippocampus = reactive aggression
• controls whether someone reacts aggressively or not
• the hypothalamus:
• responsible for the regulation of the autonomic nervous system
  = damage to this area can result in an appropriate aggressive response to a perceived threat
• the amygdala:
• responsible for attaching emotional significance to sensory
  = e.g. controls fear, anger etc..
• from the lower systems to the higher systems in the prefrontal cortex
  = where feelings are monitored + interpreted = triggers physical response
  = damage to prefrontal cortex would reduce the inhibition of the amygdala
  = result in higher levels of aggression

Question 6

neurotransmitters - neural mechanisms

Answer 6

• serotonin:
• slows down + calms neuronal activity
• inhibits the firing of the amygdala
  = lower levels of serotonin –> become aggressive easily + can’t control their responses = impulsively aggressive

Question 7

strengths

Answer 7

• research support
• technological advances
• neurotransmitters

Question 8

weaknesses

Answer 8

• non-human animals
• population validity
• dexfenfluramine drug

Question 9

research support - strengths

Answer 9

• there is strong research support for neural mechanisms for aggression
• researchers removed the main areas of the limbic system (amygdala, hippocampus etc..) in Rhesus monkeys
• monkeys displayed an absence of emotional, motor + vocal reactions normally associated w/ stimuli or situations that trigger fear or anger
• also lost the social understanding of group hierarchies
  = try to fight the more dominant/ larger members of the group
  = importance of limbic system in regulating aggressive responses

Question 10

technological advances - strengths

Answer 10

• more recent technological advances have allowed neuroimaging techniques e.g. MRI scans
• used to investigate the relationship between neural mechanisms e.g. amygdala + aggressive behaviour
• psych undertook MRI scans of 19 violent male criminals in a hospital + compared to the size of the amygdala w/ 20 normal control subjects
  = found the volume of the amygdala was significantly smaller in the 19 violent criminals
  = supporting the role of the amygdala + limbic system in aggression

Question 11

non-human animals - weaknesses

Answer 11

• research uses animals to provide evidence for aggression in humans
• there’s a difference in animal + human physiology
  = can we extrapolate the findings from animals to human aggressive behaviour
• even though they both possess similar neural structures
  = can’t be sure that aggression occurs in the same way for humans as it’s shown in animals e.g. rhesus monkeys

Question 12

population validity - weaknesses

Answer 12

• lack of population validity w/ research
• sample was relatively small
  = can findings be generalised to wider population?
• also gender bias in research
• only used males
• be careful when trying to explain aggression in females
  = beta bias - females may not be subject to the same physiological factors when explaining aggression

Question 13

dexfenfluramine drug - weaknesses

Answer 13

• psych administered the drug dexfenfluramine to 35 healthy adults
  = depletes serotonin to the brain
• researchers used a questionnaire to assess hostility + aggression levels
  = rose following admin of drugs for males, but not females
• study shows differences in gender differences in neural mechanisms
  = beta bias in neural explanations –> males + females may not be subject to the same physiological factors when

Question 14

neurotransmitters - strengths

Answer 14

• psych found support for the role of serotonin in aggressive behaviour
• allowed adult male rats to fight w/ another rat at a specific time for 10 days
• on the 11th day, rat wasn’t allowed to fight
  = rat’s dopamine levels = raised 65%
  = rat’s serotonin levels = reduced 35%
• HOWEVER raises the question: lower levels of serotonin cause aggression? OR lower levels of serotonin a response to aggression?
• cause + effect?
• explains how complex the role of serotonin is