AO1

• The limbic system is associated with the regulation of emotions and emotional behaviour
• 2 key structures in the limbic system are:

  • amygdala
  • hippocampus
• The amygdala is thought to be particularly important in regulating emotional behaviour
• The hippocampus is involved in the LTM, so allows humans and animals to store memories of past experiences
• The amygdala picks up perceived threats
• Serotonin- Under normal circumstances, the neurotransmitter serotonin works on the frontal areas of the brain to inhibit the firing of the amygdala
• Low levels of serotonin mean that people can’t control their impulsive and aggressive behaviour. Serotonin also regulates the prefrontal cortex; therefore, lower levels of serotonin affect our response to external stimuli, meaning the can’t control their emotions
• • Serotonin is an inhibitory neurotransmitter, reduces the action potential in the postsynaptic membrane
• Testosterone is the sex hormone (androgen) that controls the development of male sex characteristics. It has a role in regulating social behaviour by influencing parts of the brain responsible for emotion and decision-making
• Increased levels of aggression are thought to be due to higher levels of testosterone. 
• The hormone testosterone can affect neural transmitters and the amount of neurotransmitter that is released during the synaptic transmission.
• High levels of testosterone lower activity in the orbitofrontal cortex meaning that in an emotional situation there is more likely to be an aggressive response. High levels can also reduce serotonin, leading to aggression.