Aggression: Brain Structure

Question 1

What is the role of the prefrontal cortex?

Answer 1

it’s involved in movement, decision-making, problem-solving & planning
responsible for personality expression

Question 2

What is the role of the amygdala?

Answer 2

responsible for the perception of emotions (anger, fear, sadness) as well as controlling aggression, helps to store memories of events and emotions so that an individual can recognise similar events in the future

Question 3

What is the role of the hypothalamus?

Answer 3

responsible for producing hormones that govern physiologic functions (e.g. temperature regulations, thirst, hunger, mood, sex drive), houses pituitary gland

Question 4

Research using prefrontal cortex

Answer 4

RAINE

• murderers had lower levels of glucose metabolism in the left and right relative to controls
• low levels of functioning meant inability to regulate behaviour

PHINEAS GAGE

• damaged frontal cortex
• before accident: religious, reliable, respectful
• after accident: irreverent, impulsive, swearing
• able bodied and intellectually as capable as before but his emotional life changed

Question 5

Research using amygdala

Answer 5

RAINE
- murderers had lower levels of glucose metabolism in the left amygdala + greater right amygdala activity

BEAR
- amygdala plays a role in recognising affective & socially significant stimuli
- destructed amygdala:
in animals –> lack of fear
in man –> reduction of automatic arousal
- fearlessness, reduce emotional responses

Question 6

Research using hypothalamus

Answer 6

ALPERS (1937)

• middle-aged lawyer with tumour in medial hypothalamus
• before: well-liked, mild-mannered
• after: uncharacteristic outbursts of aggression

HESS (1928)
- able to induce aggression in cats by electrical stimulation of hypothalamus