neural & hormonal influences L1

• What system coordinates behavior in the brain?

  The limbic system
• What is testosterone thought to influence?

  Aggression from young adulthood onwards
• How does testosterone affect aggression according to Sapolsky (1998)?

  It acts on brain areas controlling aggression
• What happens when testosterone is removed in species?

  Lower levels of aggression
• What occurs when normal testosterone levels are reinstated?

  A return of aggressive behavior
• Which two key structures in the limbic system are associated with aggression?

  Amygdala and hippocampus
• What is the role of the amygdala?

  Evaluating emotional importance of sensory information
• What did Dabbs et al. (1987) measure in criminals?

  Salivary testosterone levels
• What was found about testosterone levels in violent criminals?

  Higher testosterone levels linked to violent crimes
• What does the hippocampus help with?

  Formation of memories
• How does impaired hippocampal function affect behavior?

  Prevents contextually appropriate responses
• How do changes in testosterone levels influence aggression?

  By increasing amygdala reactivity to threats
• What is the role of serotonin in aggression?

  Typically inhibits firing of the amygdala
• What happens when serotonin levels are low?

  Inhibitory effect on amygdala is removed
• What did Pardini M. (2014) find about amygdala volume?

  Reduced volume predicts severe aggression
• What was the method used in Pardini's study?

  A longitudinal study with brain MRI
• What was observed in participants with lower amygdala volume?

  Higher levels of aggression
• How does external stimulation affect the amygdala?

  It becomes more active during external events
• What does lower amygdala volume suggest about aggression?

  Increases likelihood of violent responses