Classical evidence: Rain et al Brain abnormalities in murderers indicated by PET scans

Question 1

What did rain want to do?

Answer 1

-Look at weather there was physical differences between criminals and non criminals

Question 2

Lombroso on criminals?

Answer 2

Criminals had narrow sloping forehead with large ears and protruding chin

Question 3

Aims of study?

Answer 3

-Look at direct measures of both cortical and subcortical brain function with PET scans
-Looked at a group of murders who pled not guilty by insanity
-Was thought that murders would show evidence of brain dysfunction in prefrontal cortex as well as other areas linked to violence

Question 4

What is cortical?

Answer 4

On the cortex e.g. lobes, motor cortex and Broca’s area

Question 5

What is subcortical?

Answer 5

Below the cortex, e.g. limbic system, thalamus and hypothalamus

Question 6

Expectations of raine?

Answer 6

Dysfunctions expected in the prefrontal cortex, angular gyrus, amydyla, hippocampus, thalamus and the corpus callosum
-Not in caudate, putamen, globus pallidus, midbrain, cerebellum

Question 7

Methodology- research methods?

Answer 7

Quasi- naturally occurring iv (iv NGRI murders)
PET scans- radioactive racer and glucose showing brain activity, brain scanning technique to identify areas of brain

Question 8

Methodology- Experimental technique?

Answer 8

Matched pairs
2 people in control group matched on age sex or mental health

Question 9

Methodology- Sampling method?

Answer 9

Opportunity sampling
Murders referred to the university of california to prove mental impairment

Question 10

Methodology- sample

Answer 10

82 p’s
mean age 34.3

Question 11

Methodology- sample detail?

Answer 11

6 schizophrenics
23 head injury’s or organic brain damage
3 with substance abuse
2 affective disorder
2 epilepsy
3 hyperactivity and learning disorders
2 passive aggressive or paranoid disorder

Question 12

Methodology- sample iv?

Answer 12

41 murders
39 men
2 women

Question 13

Methodology- control group?

Answer 13

41 ‘normal adults’ matched on age, sex and mental health

Question 14

Procedure- step 1?

Answer 14

All p’s injected with radioactive tracers

Question 15

Procedure- step 2?

Answer 15

All pts asked to do a continuous performance task CPT which affected areas of the brain

Question 16

Procedure- step 3?

Answer 16

Pts practiced CPT before brain scan

Question 17

Procedure- step 4?

Answer 17

When the experiment began, pts started the CPT 30 secs before injected, tis was to avoid novelty of task impacting finding

Question 18

Procedure- step 5?

Answer 18

Each PET was conducted after 32 minutes from the injection
producing 10 horizontal, cross sectional images of the brain
The scan analysed 6 cortical areas and 8 subcortical areas

Question 19

Procedure- step 6?

Answer 19

PET scan of murders compared to control group

Question 20

Findings-
Prefrontal cortex, what is this, the activity and findings?

Answer 20

-Regulayion of thoughts, actions, emotions
-Lower activity
-Lower glucose metobalism to controlls in later and mmedial prefrontal areas

Question 21

Findings-
Parietal lobe, what is this, the activity and findings?

Answer 21

This receives and process sensory input
-Lower activity
-Lower glucose metabolism compared to the controll group, in left angular gyrus, bilateral superior parietal regions

Question 22

Findings-
Temporal lobe, what is this, the activity and findings?

Answer 22

Use of sense to understand or respond
-activity is the same
-Glucose metabolism identical to control

Question 23

Findings-
Occipital lobe, what is this, the activity and findings?

Answer 23

Special process, distance, perception, discarding messaged sent from
eyes to info in the brain
-Higher glucose metabolism compared to controls

Question 24

Findings-
Amydgala, what is this, the activity and findings?

Answer 24

Processing centre for emotions
-Lower and higher activity
-Reduced activity in left amygdala and greater activity in right amygdala compared to to controls (Hemispheric asymmetry)

Question 25

Findings-
medical temporal lobe inc. hippocampus, what is this, the activity and findings?

Answer 25

Declerarive memory
-Lower and higher activity
-Reduced activity on the left and higher in the right

Question 26

Findings-
Thalamus, what is this, the activity and findings?

Answer 26

Information relay station from sence
-Higher activity
-Greater activity in right thalamus compared to controls

Question 27

Findings-
Cingulate, what is this, the activity and findings?

Answer 27

Emotion regulation
it’s the same so no different between sample and control group

Question 28

Findings-
Caudate, putamen, globus pallidus, midbrain, cerebellum, what is this, the activity and findings?

Answer 28

Learning and memory’s
same activity
Slightly higher than controls but all non significant

Question 29

3 conclusions?

Answer 29

-Reduced activity in areas of the brain associated with violence
-Biology should not be used alone to explain violent predispositions
-Findings are specific to NGRI murderes only

Question 30

Conclusion- -Reduced activity in areas of the brain associated with violence?

Answer 30

Murdered pleading NCRI have statistically difference in glucose metabolism in specific areas of the brain supporting evidence that areas or brain linked to violence
However they don’t conclusively demonstrate brown activity in NGDD murder in areas linked to violence
-Abnormal symmetry, amygdala, thalamus, M+L, hippocampus (However replication further research retinm and less selective sample needed)

Question 31

Conclusion- biology should not be used alone to explain violent predisposition?

Answer 31

Social external factors also play a part
Even they we have findings, it shouldn’t be used as evidence to not punish them
-Findings establish a casual link, Correlation not causation between brain, dysfunction and criminality

Question 32

Conclusion- findings are specific to NGRI murdered only?

Answer 32

Cant be generalised as only focusing on brain of NGRI murdered not people
who own up to crime other types of violence (lacks population validity)
-Specificity to violence as oppose to crime, can’t be applied to all crime, variable been established in the inclusion of the non violent criminal group