A01

• What are two neural influences in aggression?

  1. The limbic system

  2. Serotonin
• What is the limbic system?

  A system of subcortical structures in the brain associated with regulating emotional behaviour
• Which key structures make up the limbic system?

  1. Amygdala

  2. Hippocampus

  3. Hypothalamus
• What is the amygdala?

  - Primary role is allowing organisms to assess and respond to environmental threats and challenges

  - Evaluates emotional importance of sensory information in the environment prompting an appropriate response
• How is the amygdala implicated in aggression?

  Increased reactivity/sensitivity of amygdala has been linked to increased aggression
• What is serotonin?

  A neurotransmitter involved in the communication of impulses between neurons that has inhibitory, calming effects on neuronal firing in brain and aids in the regulation of bodily systems
• Explain how serotonin can influence aggression

  Reduced levels of serotonin remove the inhibitory, dampening effect, causing neuronal firing and activity to speed up, which leads to more impulsive and aggressive behaviour
• What is a hormonal influence in aggression?

  Testosterone
• What is testosterone?

  A hormone produced mainly by the testes in males, associated with development of male secondary sexual characteristics, but also implicated in aggression
• State and describe a study which shows support for the role of the amygdala in aggression

  • Gospic et al. (2011) gave participants a range of scenarios in a game called the Ultimatum Game and their brains were fMRI scanned to highlight activity in different brain areas
  • Found that when participants rejected unfair offers (an aggressive reaction) scans showed a heightened response by the amygdala
  • When participants were given a benzodiazepine drug (reduces arousal of autonomic system) the number of rejections halved and activity of amygdala decreased
• State and describe a study which shows support for the role of serotonin in aggression

  • Mann et al. (1990) gave 35 healthy participants dexfenfluramine, an appetite suppressant which reduces serotonin levels
  • Found this drug treatment in males (but not females) was associated with an increase in hostility and aggression scores in a questionnaire