Raine et al
Aim - investigate patterns of brain activity in murderers compared to a matched sample of
non-murderers using PET scanning
Method/procedure
- Scans of 41 murderers compared w/ a control group of 41
- Matched pairs design
- IV is whether they’re a murderer or not
- DV is the measures of brain activity and brain structure found using PET scans and
they were instructed to be medication free for 2 weeks before the scan
- PET scans measure activity in diff regions of the brain
Results
Significant differences in brain metabolism of glucose found between murderers and
controls in a no. of areas.
- Prefrontal cortex: lower activity linked to lower self-control
- Limbic system: amygdala - lack of fear , hippocampus - increased aggression
- Corpus callosum: problems controlling + expressing emotions
Summary is that they had reduced activity in some areas, notably the areas that were
previously linked to violence like the prefrontal cortex, left angular gyrus and corpus
callosum.
Abnormal asymmetries: reduced activity on the left, greater activity on the right. Applied to
some of the areas identified in the hypothesis as being linked to violence like the amygdala,
thalamus and hippocampus.
Conclusions
- Reduced activity in certain areas may be one of the many predispositions towards
violence
- The areas identified as having abnormal activity are associated w/ a lack of fear,
lower self-control, inc aggression, impulsive behaviour and problems controlling
and expressing emotions
- All of these could lead to a greater risk of committing extreme acts of violence
- However, although the study suggests that violence has a biological cause, Raine
did not conclude that there were only biological causes of violence, just that there
might be a predisposition to violence in some people, depending on env factors.
, Hall + Player (2008)
- Collection of evidence
Aim - does the written report of a crime affect a fingerprint expert’s identification of a poor
quality print and are they emotionally affected by the circumstances of the case?
Method - field exp taking place in a typical fingerprint examination room in New Scotland
Fingerprint Bureau, independent measures
Sample - 70 fingerprint experts working for Metropolitan Police Fingerprint Bureau. Mean
length of experience of 11 years. Majority were active in teams dealing with a full range of
crimes and 12 were in managerial roles.
Fingerprint from a known source used, scanned into a computer and superimposed on the
corner of a £50 note, with the detail of the note obscuring the ridge detail.
Given a crime scene report and a sheet of paper advising them of the context and including
info ab which finger it was.
All took part like it was a normal working day; come and go as they pleased but cannot
discuss the experiment/prints. Pps were assigned into 1 of 2 conditions - Low emotional
context - forgery and high emotional context - murder
Asked to consider if it was a match/not or did not have enough detail
Feedback sheet given which asked if they read the report. Also asked if the info contained
affected their analysis and how.
Results
- 81.4% read the crime scene report prior
- 52% of the high-context felt they were affected by the info given and only 6% of
the low condition
- Indicates that there is a rs between the type of context and the perceived effect on
the experts
Conclusions
- Even if experts think that a serious crime has influenced their analysis, the final
outcome is not affect
- Believe that the experienced experts in their research were less affected than the
non-experts used by Dror
- Examiners may also consider details of an individual crime that are provided with
the fingerprints as surplus to requirements.
Aim - investigate patterns of brain activity in murderers compared to a matched sample of
non-murderers using PET scanning
Method/procedure
- Scans of 41 murderers compared w/ a control group of 41
- Matched pairs design
- IV is whether they’re a murderer or not
- DV is the measures of brain activity and brain structure found using PET scans and
they were instructed to be medication free for 2 weeks before the scan
- PET scans measure activity in diff regions of the brain
Results
Significant differences in brain metabolism of glucose found between murderers and
controls in a no. of areas.
- Prefrontal cortex: lower activity linked to lower self-control
- Limbic system: amygdala - lack of fear , hippocampus - increased aggression
- Corpus callosum: problems controlling + expressing emotions
Summary is that they had reduced activity in some areas, notably the areas that were
previously linked to violence like the prefrontal cortex, left angular gyrus and corpus
callosum.
Abnormal asymmetries: reduced activity on the left, greater activity on the right. Applied to
some of the areas identified in the hypothesis as being linked to violence like the amygdala,
thalamus and hippocampus.
Conclusions
- Reduced activity in certain areas may be one of the many predispositions towards
violence
- The areas identified as having abnormal activity are associated w/ a lack of fear,
lower self-control, inc aggression, impulsive behaviour and problems controlling
and expressing emotions
- All of these could lead to a greater risk of committing extreme acts of violence
- However, although the study suggests that violence has a biological cause, Raine
did not conclude that there were only biological causes of violence, just that there
might be a predisposition to violence in some people, depending on env factors.
, Hall + Player (2008)
- Collection of evidence
Aim - does the written report of a crime affect a fingerprint expert’s identification of a poor
quality print and are they emotionally affected by the circumstances of the case?
Method - field exp taking place in a typical fingerprint examination room in New Scotland
Fingerprint Bureau, independent measures
Sample - 70 fingerprint experts working for Metropolitan Police Fingerprint Bureau. Mean
length of experience of 11 years. Majority were active in teams dealing with a full range of
crimes and 12 were in managerial roles.
Fingerprint from a known source used, scanned into a computer and superimposed on the
corner of a £50 note, with the detail of the note obscuring the ridge detail.
Given a crime scene report and a sheet of paper advising them of the context and including
info ab which finger it was.
All took part like it was a normal working day; come and go as they pleased but cannot
discuss the experiment/prints. Pps were assigned into 1 of 2 conditions - Low emotional
context - forgery and high emotional context - murder
Asked to consider if it was a match/not or did not have enough detail
Feedback sheet given which asked if they read the report. Also asked if the info contained
affected their analysis and how.
Results
- 81.4% read the crime scene report prior
- 52% of the high-context felt they were affected by the info given and only 6% of
the low condition
- Indicates that there is a rs between the type of context and the perceived effect on
the experts
Conclusions
- Even if experts think that a serious crime has influenced their analysis, the final
outcome is not affect
- Believe that the experienced experts in their research were less affected than the
non-experts used by Dror
- Examiners may also consider details of an individual crime that are provided with
the fingerprints as surplus to requirements.
