Biological explanation 2 - Role of the amygdala Flashcards
(16 cards)
What is the A01 Content?
- Structure and function of the amygdala
- The link between amygdala and aggression
- The link between the amygdala and fear conditioning.
What is the structure of the amygdala?
It is a structure of grey matter, a collection of neurones located in the temporal lobe apart of the limbic system. One in each hemisphere.
What is the function of the amygdala?
The amygdala is associated with emotional processing, it is involved in the detection of threats and processes emotional memories. It also contributes to social behaviours such as social signals in response to fear. It interacts with other brain areas to regulate emotions.
What did Raine et al do and find?
Raine investigated the brain structures of murderers and non murderers he found that there was lower activity in the amygdala of Murderers compared to control group. He suggested that this meant the murderers have a lack of inhibition for violent behaviour, fearfulness and a failure to recognise the negative effects of violence.
What is the IED?
Intermittent explosive disorder involves repeated sudden episodes of impulsive aggressive and violent outbursts in response to a situation. They cause significant distress and can have heavy consequences. This disorder is chronic and continues for years.
What is the link between IED and criminal behaviour?
People with IED are more likely to engage in criminal behaviour, such as violent crime due to the fact that aggression and impulsivity is part of the disorder.
What did Zink et al find?
He looked at the neurotransmitter vasopressin which can be linked to social behaviour and emotion e.g., fear and aggression. He did a study using fMRI scans to see the impact of vasopressin and the amygdala the data suggested that it had significance when regulating mood and anxiety disorders.
What did Corroco et al find?
Investigated the effects of the amygdala on aggression by studying people with IED, each ppt viewed images of faces at the same time as having an fMRI scan. Key differences between IED and control. Ppt with IED had high levels of amygdala activity when viewing angry faces. Shows the link between amygdala and processing aggressive emotions.
Link between size of amygdala and aggression?
Research has shown that people with smaller and potentially more under developed amygdalas are more likely to react aggressively.
How could a faulty amygdala result in criminal behaviour through fear conditioning?
When we are younger are amygdala works by helping us perceive fear, we fear the consequences of a crime through fear conditioning when we’re younger. If the amygdala does not process this fear then they may not link aggressive behaviour with punishment, they seem fearless and are more likely to become aggressive.
What was Gao study and what did it find?
A longitudinal study where over 1000 pets were tested for fear conditioning at 3 years old. They measured sweating in response to a painful noise. 20 years later the researchers found out which ppts were involved in criminal behaviour. Those who had committed crime showed no fear conditioning. Could be a fault in their amygdala. Shows a causation relationship.
Evaluation - Research support
Gospic et al created a game that was tested in a laboratory used to measure aggressive behaviour. Money is offered in a split of either a fair or unfair (social threat) way. Acceptation = split money, rejection = no money at all. Rejection is considered aggressive, they played this whilst having fMRI scans. When rejection occurred amygdala activity was higher, a sedative was given after and both rejection and amygdala levels decreased.
Evaluation - Could explain gender differences
A study researched how testosterone affects the brain (amygdala) using MRI scans they found that higher levels of testosterone made the amygdala better at perceiving a threat, it helps them become more alert and less fearful; this could explain why men who naturally have more testosterone are more likely to be involved in crime.
Evaluation - Cause and effect
It could be difficult to establish a cause and effect relationship but it does have some support of longitudinal studies e.g., Gao suggests that dysfunction comes first. Pardini also suggested this
Evaluation - Other brain area are important
The amygdala is apart of a wider system and doesn’t operate on its own. It often functions with the orbitofrontal cortex. A study showed link between these 2 in aggressive individuals. The system s complex and involves a range of structures. The dysfunction alone may not be enough to account for criminal behaviours
Evaluation - Effects of the amygdala are indirect
The amygdala ahas a role in regulating fear behaviours e.g., it accompanies the fight or flight response. Damage to this may impair function e..g, reducing empathy but does not make aggression inevitable. It is more of a risk factor than a direct cause, depends on other factors such as environment.
