AC2.1 Flashcards
What is lombroso’s theory?
-Criminal is a seperate species
-physical shape of the face and head determined a born criminal
-a born criminal is an atavism (throwback to an earlier stage of human evolution)
Lombroso’s study
-studied the bodies of executed and deceased offenders as well as examining living inmates
-large jaws, high cheekbones, prominent brows and especially long arms - features of a born criminal
-the male with 5 or more of these physical anomalies is marked as a born criminal
3 strengths of lombroso’s theory
-large sample sizes
-detailed research
-past and present criminals
3 weaknesses of lombroso’s theory
-temporal validity
-research based on his own theory
-wasn’t looking at a good demographic of crime
What was sheldons theory
That people could be classified into three body shapes which correspond with three different personality types
Endomorphic
Fat and soft
sociable and relaxed
ectomorphic
thin and fragile
are introverted and restrained
mesomorphic
muscular and hard
tend to be aggressive and adventurous
Sheldons study on college boys
-used a sample of photos of college students and delinquents rated on a scale of 1-7 in terms of resemblance to mesomorphy
-the delinquents had higher scores for mesomorphic
Sheldon and Eleanor Gleuk study
800 delinquents compared to a matched sample of non delinquents found that delinquents are more likely to be mesomorphs
5 strengths of sheldon’s theory
- used an equal and good sample size
- results supported theory
- reliability- other studies such as gleuk and gleuk supported his theory
- the most serious delinquents had a mesomorphic body shape
- Had a control group
5 weaknesses of Sheldons theory
1) using photos
2) made up a scale
3) completed the study himself
4)doesn’t account for ectomorphic and endomorphic criminals
5) body types can change
What are the two different types of twins
-identical twins (monozygotic)
-non identical twins (dizygotic)
what did early twin studies find?
A higher concordance for criminality amongst MZ than DZ twins
what was the problem with early twin studies?
it was flawed by a combination of small sample sizes and poor methods for deciding whether a twin pair was MZ or DZ
What have more recent twin studies done
addressed the early issues and they have generally produced lower estimates for the heritability of criminal tendencies than the early research
where do the most convincing twin studies come from
Denmark where researchers have access to extensive data on over 3500 twin pairs
what did Christiansen find
MZ concordance rates of 52% compared with 22% for DZ twins
3 strengths of twin studies
1) denmark had a large sample size
2) findings are supporting that MZ twins are more criminal
3) more recent studies are more valid
3 weaknesses for twin studies
1)the early studies weren’t representative
2) only looking for one explanation (bias)
3) twins in the studies could’ve lied
What did adoption studies look at
relatives,siblings and twins that are adopted at a young age. This means they share genes but not the same environment
-by taking environment out the picture we can be sure that genetics are the reason of criminality
What did the adoption studies involve
comparing the behaviour with birth parents
-behaved more like their biological parents but their environment has been surrounded by their adoptive parents (genetic basis for criminality)
-behaved more like the adoptive parents= environmental basis for criminality
a strength of adoption studies
sample size more people available
2 weaknesses of adoption studies
1)researcher bias
2) Age of adoption may mean the children have already been influenced by their biological parents or foster environment
what is the XYY syndrome?
The idea that chromosome abnormalities might cause criminal behaviour
what did researchers discover xxy syndrome
in the 1960s they discovered that males with an extra Y chromosome are more likely to be violent and criminals. The condition is not inherited
what is XYY linked to
slow learning
what does Jacobs XYY theory show us about reasons why people commit crime
-Some XYY men have an increase in aggression these are labelled “super males”
Jacobs studies
-chromosome survey conducted at a maximum security hospital. 9/315 patients had the extra chromosome
2 strengths of Jacobs XYY theory
1)results supported research
2)prince and what more found links between XYY and property crime
2 weaknesses of XYY syndrome
1)even if they have the syndrome doesn’t prove that it was the cause of their violence
2)offers no explanation for female criminality
3)Low IQ link may make them easier to get caught and that’s why there in prison
Sex hormones
-over production of testosterone linked with crimes like rape and murder
-levels peak between puberty and early 20s and this correlates with male crime rates
Serotonin
-Some studies show that low levels of serotonin are linked with higher aggression
serotonin study
conducted on 29 antisocial adults and children and low levels of serotonin were found in all of them
testosterone case example
american body builder beat a man to death after overdosing on steroids
blood sugar levels
low blood sugar (hypoglycaemia) can trigger aggressive reactions
substance abuse
abuse of drugs such as cocaine and crack and steroids correlate with violence
two strengths of biochemical explanations
1) there is strong medical evidence to support that substances and hormone levels can affect mood,judgment and aggressions
2) biomedical factors are recognised by the courts and in some case written into law
two weaknesses of biochemical explanations
1)might create a pre disposition to offending but need an environmental trigger
2)the effect of biochemicals on aggression might be overstated e.g might lead to verbal aggression rather than physical
phineas gage
-severe damage to frontal lobe of the brain after accident on the rail road
-major personality change
-gave us insight into how important this area of the brain was for controlling emotions and regulating behaviour
RAINE
-used PET scans to study the brains of impulsive killers
-damage to the pre frontal cortex in the brains of criminales
Charles Whitman
-killed his mother and wife
-then shot three people
-and opened fire at random and killed a further 11
-it was found that he had a tumour pressing on his amygdala (processed emotions)
3 strengths of brain injuries and disorders
-in extreme cases brain injury or disease has led to extreme changes in personality
-correlation between abnormal EEG readings and criminality
-prisoners are more likely than non prisoners to have brain injury
3 weaknesses of brain injury/ disease
1)brain disease/injury is rare personality is likely to be a more important factor
2)it’s not clear abnormal brain wave activity causes criminality some psychopathic criminals have normal EEG readings
3)prisoners higher likelihood of brain injury could be a result rather than a cause of their criminality e.g. getting into fights
