Criminal psychology - Topic 1&2

Topic 1 - What makes a criminal

Physiological and non physiological explanations

Raine et al

Biological strategies for preventing criminal behaviour

BR - Lombroso

Individuals have evolved to possess certain criminal features

Criminals are a subspecies of humans identified by features such as; large ears, defined jawline, narrow sloping brow or physical abnormalities

BR - Sheldon

Criminal body types

Identified three body types; ectomorphs, mesomorphs and endomorphs

Through looking at common body types amongst inmate populations, concluded mesomorphs were most likely

They have a more muscular build - may prejudice others to treat them like criminals or may recognise that they can gain rewards through force

BR - Jacobs

Men born with the genetic abnormality of XYY were more aggressive (0.001% of pop but 1.5% of criminals)

Research showed that having biological parents with convictions increases your chance of having a record

However same can be said for adoptive parents

BR - Bandura and SLT

You know herrrr

Trzesniewski - Self esteem

Adolescents with low self esteem were more likely to engage in criminal activity

Linked to humanist explanation as those individuals have failed to reach self actualisation due to no access to self esteem sources

BR - Self fulfilling prophecy

Jahoda - Found that in some cultures children are assigned soul names depending on which day of the week they were born

In ashami cultures, boys born on a wednesday (22%) are thought to be aggressive and violent whereas monday boys (7% of crime) were calm

Labels result in mistreatment which leads to criminal activity

Raine - Aim

To study brain activity in murderers and non murderers using PET to find out if there were differences in areas associated with violent behaviour

Raine - Sample

EG - 41 murderers (39m, 2f) with a mean age of 34.3yrs

Each had been charged with murder/manslaughter and pleaded NGRI

Control - Matched for sex and age, and for six participants, schizophrenia

No ppts took any medication for 2 weeks prior

Raine - Design

Quasi experiment

Matched ppts design

Raine - Procedure

30 seconds before ppts completed a CPT, they were injected with a glucose tracer for a PET scan (insuring that the novelty of the task wasnt a factor)

They were allowed to practice the CPT beforehand

CPT continued for 32 minutes, PET images of 10 horizontal slices were taken and analysed using techniques

Raine - Techniques

Cortical peel - used for lateral areas such as areas of the temporal lobes

Box - used for medial areas such as the superior frontal gyrus

Raine - Results

Murderers had significantly less activity in the corpus collosum (0.56 compared to 0.68)

They had abnormally asymmetrical activation in areas of the limbic system

Raine - Conclusions

Areas found to have abnormal activity were associated with aggressive behaviour, a lack of fear and problems with controlling and expressing emotions (amygdala) +++

Also associated with learning conditioned emotional responses and effects on areas associated with learning could lower IQ