Raine et al

• What is the classic study for biological psychology

  Raine et al 1997
• Raine Aim


  To discover, using PET scans, whether there are brain abnormalities in murderers who plead NGRI (not guilty by reason of insanity)
• Raine Sample


  - two groups used in this study with 41 people (39 Ms and 2 Fs) in each group

  - E group were charged with murder pleading NGRI

  - C group matched on illnesses age and sex so the only reason for Dif is killing someone
• Raine IV


  whether the participant had committed murder/ manslaughter or not.
• Raine DV


  the results of the PET scans.
• Raine design


  natural experiment because the researchers do not have total control over the independent variable.

  That is, the participant group are pre-existing and so participants cannot be randomly placed in the conditions of the experiment.
• Raine Procedure


  - Participants were required to perform a Continuous Performance Task (CPT) involving the participant staring at a screen while various blurred symbols appear.

  - The participant was to press a button when a particular symbol appeared, thus requiring constant attention to the screen.

  - They did this task for 10 minutes as a practice trial.

  - A radioactive glucose tracer (flurodeoxyglucose) was then injected into the participant.

  - After a further 32 minutes of the task, the subject's brains were PET scanned in order to determine the glucose metabolic rate throughout the brain to determine the level of activity in various regions of the brain.
• Raine Results


  -Lowerlevels of brain activity in both hemispheres compared to the control group in thePrefrontal Cortex-Lowerlevels of brain activity compared to the control group in various areas of theparietal cortex-Lowerlevels of brain activity compared to the control group in both hemispheres in theCorpus Callosum- There wereabnormal asymmetrical levels of limbic system activity(RH higher than controls LH lower) compared to the controls in the: Amygdala, Thalamus and Hippocampus
• Raine Conclusion Overall


  - Results could predispose a person towards violent behaviour.

  - Abnormal functioning of theamygdala, which is responsible for emotional processing, results in the murderers beingfearless. This fearlessness could result in the increase chance of acting violently.- Thehippocampusandthalamushave been related to learning and it is possible that abnormal activity here could result in criminals being unable to modify their own behaviour bylearningform the consequences of their actions- 4. Raine et al. suggest that theright hemisphereis implicated in generating negative mood. This is normally regulated by theleft hemisphere.However, because thecorpus callosumis not as active in murderers compared to controls, they would be unable to regulated the negative mood and possible become more violent due to the low mood.
• Raine suggestions about Prefrontal Cortex

  Lack of functioning in theprefrontal cortexresults in the reduced ability to regulate the activity of the limbic system and thuscontrolnatural aggressive responses to threatening stimuli.
• Raine suggestions about Amygdala


  Abnormal functioning of theamygdala, which is responsible for emotional processing, results in the murderers beingfearless. This fearlessness could result in the increase chance of acting violently.
• Raine suggestions about Hippo and Thala

  Thehippocampusandthalamushave been related to learning and it is possible that abnormal activity here could result in criminals being unable to modify their own behaviour bylearningform the consequences of their actions
• Raine suggestions about Hemispheres


  - Theright hemisphereis implicated ingeneratingnegative mood. This is normallyregulatedby theleft hemisphere.- However, because thecorpus callosumis not as active in murderers compared to controls, they would be unable to regulated the negative mood and possible become more violent due to the low mood.
• Raine Generalisability +-


  + Large sample used for an unique characteristic

  - Mainly males used (may be representative of proportion of male murders)

  - Atypical as consisted of a certain group of offenders
• Raine Reliability +-


  + Standardised procedures: same scanner (PET), same continuous performance task for 32 mins

  + Quantitative data technique (PET)
• Raine Application


  - pre-dispositions for committing violent criminal acts could be identified using PET scans.

  - cause and effect between brain dysfunction and violent murder is NOT established in this study.

  - Raine himself suggests that caution is needed. He emphasises that having certain kinds of brain activity does not mean that somebody will be a violent offender. i.e. PET scans cannot and should not be used as a diagnostic tool to predict violent offending
• Raine Validity +-


  + Well controlled (no medication for 2 weeks, age, sex and illness matched)

  - Could not control upbringing or situation of offence

  - Reductionist as only bio

  - PET scans' resolution is lower than other tech
• Raine Ethics +-


  + Approved so guidelines were upheld: consent, limited harm (only one injection)

  - Had to be off meds (schizophrenic)

  - Pressure as part of the NGRI plead (also +)