Forensic Psychology Flashcards
Lombroso
Atavistic form theory.
Conducted post mortems to study.
Argued that a criminal is a separate species.
Criminality is heritable.
People could be born criminal.
Criminality could be determined by the physical shape of the head and face.
Criminals had atavistic features (primitive)
Examples of atavistic features.
Large jaw
High cheekbones
Insensibility to pain.
Lombroso study
Examined features of 383 dead criminals and 3839 living ones. He said that 40% of criminal acts could be accounted for by atavistic features.
Features of a murderer.
Bloodshot eyes and curly hair.
Features of a sex offender.
Large lips and ears.
Features of a female criminal
Short and dark hair.
Strengths of Lombroso.
Very influential. Beginning of offender profiling.
He labelled prisons as criminal universities which links to reoffending rates.
Recent study in China put photos of 1856 men into artificial intelligence programme. Half of which were criminals.
Wrongly flagged innocent men as criminals 6% of the time, but correctly identified criminals 83%.
Limitations of Lombroso.
Inaccurate, not everyone with atavistic features are criminals.
Goring (1913) used a non criminal control group and found no significant difference in physical features of criminals and non criminals.
Does not account for possible disfigurement.
Deterministic - assumes we cannot escape destiny.
Scientific racism - De Lisi (1912) said that many of the atavistic features ere specific to people of African descent.
Biological explanations of offending behaviour
Atavistic form theory. Genetics and neural.
Genetics in explaining offending behaviour.
Offending behaviour is inherited.
Twin and family studies are used to measure concordance rate.
Twin studies, adoption studies, candidate genes and diathesis stress model.
Twin studies
Twin studies - Christiansen (1977) examined 3500 twin pairs in Denmark and identified the following concordance rates for criminal behaviour. MZ male = 35%, DZ male = 13%, MZ female = 21%, DZ female = 8%.
Shows that there is a genetic factor as MZ twins have a higher concordance rate and they share 100% DNA.
However, it does not account for nurture, therefore adoption studies can also be used.
Adoption studies
Adoption studies - Crowe (1972), group of adopted children whose biological mother had a criminal record (50% of adopted children also had a criminal record by the time they were 18) and a control group (only 5% with criminal record).
Shows that regardless of the environment, children are biologically predisposed to criminality.
Candidate genes
Candidate genes - Brunner et al (1993), analysis on large family in Netherlands (number of which were responsible for various counts of anti social and criminal behaviour.
Males had a genetic condition with defective MAOA gene - causing abnormal levels of serotonin which leads to unregulated moods and possibly criminal behaviour.
Recent analysis of 800 Finnish offenders found low MAOA activity and low activity from CDH13 gene (controls impulsive behaviour). 5-10% of all severe violent crimes in Finland is attributable to the MAOA and CDH13 gene types.
Diathesis stress model.
Vulnerability and interactions cause mental health issues. High vulnerability requires low stress and low vulnerability requires high stress.
Genetic and external factors could be responsible for criminality.
These factors could be: criminal activity, alcoholism, drug use, ACEs (adverse childhood experiences.
Strengths of genetic explanations.
Supporting nature debate - provides a better understanding for genetic causes. However fails to consider external factors.
Limitations of genetic explanations
Most of genetic research on criminal behaviour looks at a limited range of criminal behaviour, only looks at crimes involving violence. This is a limitation because there is lots of other crimes that genetics fails to explain (fraud, theft).
Further research is needed to establish a link between genes and non-violent crimes.
Excuse for criminal behaviour, suggests that people cannot escape crime. Stephen Mobely (murderer) tested for MAOA gene and therefore said he could have been ‘born criminal’ and is not responsible for his behaviour. Judge disagreed, so it was not used as a defence and he was executed in 2005.
Strengths of diathesis stress model in explaining offending behaviour
Supporting research - Mednick et al (1984), 13000 Danish adoptees. Neither biological or adoptive parents are criminal = 13.5% adoptees criminal, either biological parents or adoptive parents criminal = 20% of adoptees, both adoptive and biological parents criminal = 24.5% adoptees.
Increases external validity
Limitations of diathesis stress model in explaining offending behaviour.
Still only small number of people becoming criminal, 75% not criminal.
Neural explanations for offending behaviour.
Differences in the brains of offenders and non-offenders.
Neurochemical - internal
Neurophysiological - external
Neurochemical
Serotonin is associated with criminal behaviour, this is shown through cases looking at a defective MAOA gene causing criminal behaviour as it affects enzymes that break down serotonin.
An increase in dopamine can cause increase in certain behaviours such as aggression and impulsivity. This can be exaggerated in people who have deficits in their reward system as they do not gain pleasure from normal activities. The increase in excitement causes them to repeat behaviour.
Strengths of neurochemical explanation
Scerbo and Raine (1993) - abnormally low levels of serotonin in 29 studies examining offending behaviour.
Cherek et al (2002) - investigating impulsivity and aggression in males with history of criminal behaviour. 1/2 given placebo, 1/2 given an SSRI antidepressant, after 21 days those experimental group showed significant decrease in impulsive responses and aggression.
Limitations of neurochemical explanation
Issue of cause and effect, unable to know if low serotonin is causing criminal behaviour or criminal behaviour is causing low serotonin, as offenders are put in prison which could lead to depression.
Neurophysiological
Amygdala - implicated in emotional behaviour. It has a widespread influence of brain functioning as it is neurally linked to other parts of the brain, such as the prefrontal cortex, hippocampus and hypothalamus. Major role in how we assess and respond to environmental threats.
Amygdala dysfunction = proactive aggression (premediated, cold blooded), linked with reduced amygdala function.
Reactive aggression (spontaneous, angry), linked with increased amygdala function.
Frontal lobes - linked to self control and regulation of impulsive behaviour. Raine et al (1997) - 41 violent offenders compared activity of pre-frontal cortex to 41 non-criminals using PET scans. Offenders showed significantly less activity in pre-frontal lobe, suggesting less control over impulsive behaviour.
Strengths of neurophysiological
Amygdala:
Glenn et al (2009) - 17 participants with varying degrees of psychopathy, fMRI scans while making judgements about dilemmas, association found between psychopathy and reduced amygdala activity.
However this research uses a small sample size and the dilemmas which the participants had to make judgements on lacked external validity.
Coccsro et al (2007) - people with intermittent explosive disorder showed high levels of amygdala activity when their viewed angry faces (using fMRI)
Frontal lobes:
Brower and Price (2001) - link between frontal lobe dysfunction and violent crime.
Kandel and Freed (1989) - frontal lobe damage and antisocial behaviour, tendency for such individuals to exhibit emotional instability and this is linked to impaired functioning in the frontal lobes
Limitations of neurophysiology.
Research into neurophysiology is often correlational, so there is no clear way to show cause and effect. Structural abnormalities found my Raine could be a cause of offending behaviour or the result of an environmental factor.