The Raine Study - Describe

Question 1

What was the experimental design?

Answer 1

Matched pairs design

Question 2

What type of experiment was it?

Answer 2

Quasi-experiment

Question 3

What was the IV and the DV?

Answer 3

• IV = NGRI
• DV = Brain differences

Question 4

Describe the experimental group.

Answer 4

• 41 participants, 39 men & 2 women.
• Mean age of 34.3
• All charged with murder / manslaughter and pleaded NGRI.
• Referred to the University of California for examination to prove their diminished capacity.
• 6 were schizophrenic and 23 had a history of head injury / brain damage.

Question 5

What was the experimental group instructed to do 2 weeks prior to scanning?

Answer 5

Be medication free

Question 6

Describe the control group.

Answer 6

• Each murderer was matched with a normal individual of the same sex and age.
• The 6 schizophrenics were matched with 6 schizophrenics from a mental hospital.
• The other controls had no history of mental illness, nor any significant physical illness.
• None were taking medication.

Question 7

What sampling method was used?

Answer 7

Opportunity sampling

Question 8

What type of scan was used to study the active brain?

Answer 8

PET scans

Question 9

What is the name of the tracer and what does it do?

Answer 9

• FDG
• The tracer is taken up by active areas of the brain, making it possible to compare the brains of the experimental and control group.

Question 10

What does the CPT do?

Answer 10

Aims to activate the target areas of the brain to see how they function.

Question 11

What is step 1 of the procedure?

Answer 11

Participants were given a chance to practice the CPT before receiving the FDG injection.

Question 12

What is step 2 of the procedure?

Answer 12

30 seconds before the injection, participants start the CPT so the initial task wouldn’t be FDG labelled.

Question 13

What is step 3 of the procedure?

Answer 13

• 32 minutes after the FDG injection, PET scans were done of each participant.
• 10 horizontal pictures of the brain were recorded.
• Precise details of the scanning techniques were recorded so that the study could be replicated.

Question 14

What brain differences were found?

Answer 14

• Reduced activity in the brains of NGRI in areas previously linked to violence, e.g. the prefrontal cortex.
• Increased activity in the brains of NGRI in areas not previously linked to violence, e.g. the cerebellum.
• Abnormal asymmetries were found = Reduced activity on the left side of the brain, greater activity on the right.

Question 15

How can violent behaviour be explained?

Answer 15

The disruption of a network of interacting brain mechanisms.

Question 16

How was the study designed?

Answer 16

• Carefully
• Matched controls
• Large sample

Question 17

What DON’T the findings show?

Answer 17

• Violent behaviour isn’t determined by biology alone; social, psychological, cultural and situational factors also play important roles in predisposition to violence.
• They don’t show that murderers pleading NGRI are not responsible for their actions.

Question 18

What does reduced activity in the prefrontal cortex show?

Answer 18

• A deficit linked to impulsivity.
• Loss of control.
• Immaturity.
• inability to modify behaviour.

These are all associated with increased aggressive behaviour.