Criminal Behaviours Biological explanation 2: The role of the amygdala

• What does it do?- It helps people feel certain emotions and to perceive them in other people too. It allows us to react quickly to danger.

• What functions does it have?

• What processes is it involved in?- It is involved in the message of danger which is received directly from the thalamus.

  • How could this involve criminal behaviour? - They may not feel emotions for the victims and the impact that the crime will have on them. Another explanation is that the amygdala could be damaged and therefore, they may not fear consequences.

  • Link to Raine et al?- They found that the criminals had abnormal asymmetries in the amygdala, and that the activity in the left hemisphere (which includes the amygdala) and it was increased in the right hemisphere.

• Evidence for the role of the amygdala in aggression comes from research on people with Intermittent Explosive DIsorder (IED).

• People with IED are more likely to engage in criminal behaviour, in particular violent crime, due to the aggression and impulsivity that is part of the disorder. There is evidence that high levels of amygdala activity may be the cause of this disorder.

  • Coccaro et al (2007)- Investigated the effects of the amygdala on aggression by studying those with IED. They found IED participants showed high levels of amygdala activity when they viewed angry faces. Which suggests a link between amygdala activity and the processing of aggressive emotions.    

  • Matthies et al (2012)- There has been many pieces of research suggesting a link between the amygdala and the modulation of aggressive behaviour. 20 healthy voluntary participants took part in morophoric brain scans, and assessments were conducted to rule out any psychiatric disorders. All volunteers scored in the normal range of lifetime aggression. There was a highly significant negative correlation between amygdala volumes and trait aggression.

• A dysfunction of the amygdala means the child cannot identify the social cues that indicate threat i.e. angry faces. Therefore, they are unable to establish the link between the punishment and their aggressive behaviour.

• Gao et al (2010)- A longitudinal study tested participants for fear conditioning at the age of three. When those participants aged 23 and committed crimes, they had shown no fear at the age of three they were effectively “fearless”.

  • Feinstein et al (2012)- Support: While being provoked, taken to haunted houses etc. SM showed minimal levels of fear behaviours.

  • Feinstein et al (2012)- Contradict: After real life traumatic events she began to show basic emotions

Limitations: Individual - The findings won’t apply to everyone and won’t be generalisable.

• The amygdala’s role in aggressive behaviour is well established. Many studies have found that increase amygdala activity is involved in aggression.

• Gospic et al (2011)- Used a laboratory-based method of measuring aggressive behaviour. It involves two players, the Proposer and the Responder, and a sum of money. The Proposer offers to split the money in a ‘fair’ or ‘unfair’ way. If the responder accepts then the money is split accordingly. However, if the responder refuses the offer then both get nothing. They found that when responders rejected unfair offers, amygdala activity was heightened and quicker.    

• Derntl et al (2009)- Used MRI scans to investigate the effect of testosterone on amygdala activity in healthy male participants. They found that increased levels of testosterone improved the amygdala’s ability to process threat-related stimuli.   

  • This could possibly explain why violent crime is much more common among males, as they have a higher concentration of testosterone than women.

• The theory could be argued to be reductionist. This theory ignores the role of society and culture. All criminals are assessed equally regardless of socioeconomic background or education. The real causes of crime are varied, and complicated. It is probably better to take an interactionist approach seeing genes, brain structures, society, upbringing and personality all interacting to cause criminal behaviour.

Another ethical issue is that all of these theories place the blame for offending inside the offender. It could be argued that by doing this it absolves society and the government of any responsibility. It has been argued that the main reason for crime is social inequality and poverty. By placing the blame within the criminal, it is ignoring the real reasons for crime.