3.1.3 Aggression-Brain Structure Flashcards
What is the role of the pre-frontal cortex?
- Decison making
-Personality - Planning
-Self control
How does Raine’s (1997) research relate to the pre-frontal cortex as an explanation of aggression?
He found lower activity in both hemispheres of 41 murderers pleading NGRI which means their abnormality could lead to impulsivity and lack of self-control which can materialise in the form of aggression.
How does the case study of Phineas Gage relate to the pre-frontal cortex as an explanation of aggression?
E: The influence of the PFC on aggressive behaviour can be shown through the case study of Phineas Gage, Ggage was known to be amiable and a hard worker until a construction accident occured and a metal rod pierced through Gage’s jaw, his PFC and exiting through the back of his head. Following the accident, Gage was described to be aggressive and uttered profanities often, the evidence for Gage’s aggression can be explained by the damage to his PFC based on his rapid change in behaviours.
W: The nature argument suggests that Gage’s abnormal personality change was due to predisposed factors of the damage to his PFC which may have intercepted Gage’s communications within his brain’s limbic system, therefore his physiological responses such as fight or flight and aggression regulation would be irregular so Gage would have no free will over his aggressive actions which supports nature’s argument for aggression.
What is the role of the amygdala?
- Perception of emotions (fear, anger, etc)
- Controlling aggression
- Helps to store memories of events and the emotions of them
How does Raine’s (1997) research relate to the amygdala as an explanation of aggression?
He found that there was reduced activity in the left side with a difference of 0.03 between murderers and non-murderers which leads to reduced autonomic arousal in offenders resulting in a lack of fear of consequences of being aggressive.
How does the case study of Charles Whitman relate to the amygdala as an explanation of aggression?
Amygdala can be linked to aggression through case of Charles Whitman, a marine veteran, who in 1966, murdered his mother + wife, then carried out a mass shooting whereby 16 people were killed before Whitman was shot by Austin police officers.
E- Post mortem, Whitman was found to have a tumour - a glioblastoma- pressing against his amygdala. The tumour may have influenced aggression on Whitman by interrupting the chemical messengers sent between the amygdala and the other parts of the brain, including the limbic system. This means that Whitman’s physiological responses such as fight or flight, impulse and emotional control may have had irregularities in terms of controlling aggression.
W- This is a strength as the tumour pressing on Whitman’s amygdala supports the nature aspect of biological psychology, whereby our behaviour is determined by pre- disposed characteristics or biological characteristics that an individual can’t control. The tumour is pre-disposed, meaning that Whitman had no free will over his aggressive actions.
What is the role of the hypothalamus?
-Thermal regulation
- Hormonal control
How does Hess’s (1977) research relate to the hypothalamus as an explanation of aggression?
He found that electrical stimulation of the hypothalamic attack area (HAA) in rats and cats elicited ‘biting attacks’ showing that abnormalities to functioning in this area can cause aggressive responses.
How does the case study of Alpers relate to the hypothalamus as an explanation of aggression?
He had a tumor in his hypothalamus which caused a mild-mannered man to act aggressively.
EACH-Application
P - Yes
E - It shows that people with damage to areas of their brain such as the pre-frontal cortex can lead to impulsive behaviour
E - Therefore we can identify those who may be more likely to commit violent crimes and implement treatments or ways to reduce the risk to reduce crime rates
EACH-Credibility
P - Interactionist
E - Brain damage may result from the environment causing aggressive responses due to damage on biology
E - Therefore showing that nature and nurture can interact giving this explanation for aggression more credibility
P - Deterministic
E - It says that aggression is down to abnormalities in certain brain areas
E - Therefore saying that we are not in control of our own behaviour but humans are more complex
EACH-How?
Strengths
P - Raine’s (1997) research has high inter-rater reliability
E - Used a PET scan to measure brain activity with a CPT of spotting targets for 32 mins
E - Multiple researchers can look at the images and so increases objectivity and inter-rater reliability
P - Case studies have high vailidity
E - They look at an individual and their situation in high levels of detail providing rich in-depth qualitative data
E - This helps to provide understanding into how the brain works and how it can be affected to cause aggression with many different methods
EACH-How?
Weaknesses
P - Hess’s (1977) research has low generalisability
E - He used ppts of rats and cats to electrically stimulate their hypothalamic attack area
E - Therefore there may be qualitative differences in human responses to abnormalities in these areas and how the aggressive behaviours manifest as humans don’t elicit ‘biting attacks’
P - Research has low validity
E - There is no empirical evidence of how the person was before they experienced brain damage
E - Therefore we cannot establish cause and effect of brain damage causing the change in behaviour as it may be due to other factors such as stress from environment
