amygdala

• what is the amygdala?

  bihemispherical structure in the brain made of grey matter > neurons packed together
• where is the amygdala found?

  medial temporal lobe - mediates and communicates from one part to another

  limbic system - helps communicate (emotions, decisions etc) and includes PFC, HP, HT
• what is the amygdala involved in?

  fight or flight > detect and respond to threat

  guard dog
• Over Active

  perceive mild / non-threatening situations as more threatening than they actually are

  respond in an overly aggressive way > kill or be killed

  e.g. lash out from dirty look
• Over Active - Study

  Coccaro et al (07) - fMRI

  IED and normal, showed images of faces

  shown angry face > IED - increased amygdala activity
• Under Active

  don't learn to regulate behaviour and find less aggressive, more socially acceptable ways to behave > grow up - fearless, overly aggressive and antisocial

  fail to recognise threat > immune to fear conditioning in childhood > don't associate stimulus with fear

  techniques to socialise children don't always work

  e.g. don't react or detect threat from facial expression or tone of voice
• Under Active - Study

  Gao et al (10)

  1795 participants tested for fear to noise (sweat) at age 3

  when they were 23 > those who committed a criminal act / were criminals > showed no fear

  lack of amygdala initiated fear in childhood > CB