Unit 2 - Criminological theories - 2.1 Describe biological theories of criminality Flashcards
Physiological theories - Lombrosso’s theory ‘born criminals’
According to Lombrosso, how do criminals differ from non-criminals?
Physically different
What research did Lombrosso carry out?
He spent years measuring and recording details of the heads and faces of thousands of prisoners
What did Lombrosso conclude from his research?
Criminals could be identified by their distinctive physical features such as large jaw, handle-shaped ears and high cheek bones
What is meant by ‘Atavism’?
Criminals are a throwback to an earlier primitive stage of evolution
Why were criminals like savages?
They were pre-social, unable to control their impulses and have a reduced sense of pain hence why they usually have tattoos
Explain why Lombrosso thought people were ‘born criminals’
He believed you could read their bodies for physical characteristics and that if they were born with specific physical characteristics you were destine to be criminal
What were two other types of criminals that Lombrosso identified?
‘Insane criminals’ and ‘epileptic criminals’
Sheldon’s somatotypes theory
How did Sheldon see criminals, similarly to Lombrosso?
Physically different from non-criminals and he believed certain body types are linked to criminality
Briefly describe the three somatotypes identified by Sheldon
Endomorph - rounded, tend to be fat, lacking muscle or tone with wide hips. sociable, relaxed, comfortable and outgoing
Ectomorph - thin and fragile, lacking both muscle and fat. They are flat chested with narrow hips and shoulders. Thin face and high forehead. Personality is self-concious, fragile, emotionally restrained and thoughtful
Mesomorph - muscular and hard bodied with little fat. Broad shoulders and thin waist. Personality is adventurous, assertive and sensation seeking
According to Sheldon who is the most likely to commit crime and why?
Mesomorphs - attracted to risk taking and their imposing physique can be an important asset in crimes like murder and rape
Genetic theories
What does the Cambridge study in Delinquent development show about crime in families?
Out of 397 families, half of all the convictions came in just 23 families
What did Osborne and West find out about crime in families?
Sons of criminal families were much more likely to have a criminal record too
Genetic studies - Twin studies
Describe how genetic theories explain why crime runs in families
Families who share blood share many of the same genes so therefore if a member has ‘criminal genes’ it is likely that their blood relatives will have them too, this is why criminals often have relatives who are criminals.
Why are twins used to test Genetic theories?
This is because Identical or Monozygotic twins share exactly the same genes so therefore if one twin is criminal the other twin is likely to be criminal too.
What evidence did Christiansens twin study in Denmark show?
He studied 3,586 pairs of twins. He found that their was a 52% concordance rate between identical twins where one twin has a conviction, there is a 52% chance the other will have a conviction. However, in non-identical twins there is only a 22% chance
What did the study of Ishikawan and Raine on twins show?
44% concordance rate for identical twins and only 21.6% for non-identical twins
Adoption studies
How do adoption studies test for genetic causes for crime?
Compares adopted children’s behaviour to their biological parents (genetic) and to their adopted parents (environment)
Explain how adoption studies could show a genetic link to crime
An adopted child shares the same environment as their adoptive parents, but the same genes as their biological parents. If we find that an adoptee’s behaviour in regard to criminality is more similar to their parents behaviour, this would support the genetic explanation
What does the evidence from Mednick’s Et Al study show about the genetic causes of crime?
He examined 14,000 adopted sons. They found that sons were 20% more likely to have a criminal record if a birth parent did and 14.7% if an adopted parent did.
Twin and adoption studies
Why are twin studies and adoption studies useful for researchers?
They help researchers to find out what we get from our genes and our environment
What are the Monozygotic and Dizygotic twins?
Monozygotic - twins that develop from the same egg so share 100% of genes
Dizygotic - twins that develop from separate fertilised eggs so share 50% of genes
What do Mono and Dizy twins both share?
Same environment like womb conditions
How are dizygotic twins different to regular twins?
Dizy twins share the exact same environment but regular siblings don’t eg parents are stricter with older child
What might doctors want to find out about Schizophrenia?
Whether it results from a genetic compound or effects from environments
How do twin studies allow scientists to isolate nature or nurture?
They can allow a constant environment but different genes
What problems are there with twin studies?
Mono twins might share more environmental similarities compared to dizygotic twins
How do adoption studies allow us to understand the difference between nature and nurture?
If a child is more similar to birth parents or adoptive parents
Why might adoptive studies not be ideal for understanding nature vs nurture?
There could be incomplete information about biological parents and adopted parents could be too similar to the biological parents
How can adoption and twin studies be combined?
Two twins are adopted by different families
What are the problems with twin adoptions?
Adoption isn’t random and the families may have very similar environments as adoption is expensive so may be a wealthy environment for both twins
Summarise how twin and adoption studies could highlight whether something has a genetic cause
Monozygotic twins don’t have the same genes as Dizygotic twins
MZ twins raised together = identical twins raised apart
adopted child = biological parent
Summarise how twin and adoption studies could highlight whether something has an environmental cause
Mz twins = Dizygotic twins
MZ twins raised together different environment from MZ twins raised apart
adopted child = adoptee parents
Jacob’s XYY study
Describe the normal sex chromosomes for Males and Females
XY and XX
Describe the ‘Super male’ syndrome
People born with extra Y chromosome = XYY
What does this cause for the person with super male syndrome?
Tend to be tall, well built and lacking intelligence
Outline the evidence that supports this view that XYY causes criminality
Study of imprisoned criminals in secure physciatric hospitals where a higher than average proportion of the inmates were found to have the XXY syndrome. Many had histories of assault and aggression. Price and Whatmore found that XYY men tend to be immature and unstable
What did Price and Whatmore found out about patients with ‘super male syndrome’?
Price and Whatmore found that XYY men tend to be immature and unstable, with a strong tendency to commit seemingly motiveless property crime
Brain injuries and disorders
What have studies shown about the effect of brain injuries on criminality?
Certain diseases, injuries and malfunctions of the brain can be linked to criminal behaviour. Studies have shown that prisoners are more likely to have suffered brain injuries
What happened to Phineas Gage?
A dynamite explosion caused a metal poll to launch into his eye socket and into his brain taking parts of his frontal lobe with it
What aspects of Gage changed after?
His personality before was kind and caring but after he became rude and aggressive and a menace
What could Gage do normally after the accident?
Read, write, sing and talk
What was the ‘Vital force’ theory?
The idea that any part of the brain can do any function. Gages case shows that even with a missing part of the brain it can still function normally
What did the ‘localisers’ think about the brain?
That different parts of the brain do different things shown by Gage as when he lost his frontal lobe his personality changed hugely
Explain why partly both the theories are correct
The brain has localised specific functions but it also has non-localised things like neurones that appear everywhere In the brain
From recent studies, what is the impact of frontal lobe damage?
Causes behaviour spontaneity, difficulty understanding information and following rules
Why does this help us to understand why brain damage may affect criminality?
People with brain damage find it hard to follow rules and like to take risks. This may explain why they often commit crimes.
Diseases
What diseases have been linked to criminality?
Senile dementia, Huntington’s disease and Brain tumours have been linked to forms of deviance or anti-social behaviour
Diseases
What did the epidemics of encephalitis lethargic cause for children in the 1920’s
It was linked to destructiveness, impulsiveness, arson and abnormal sexual behaviour
Biochemical explanations - Sex hormones
Describe how testosterone can be linked to criminality
Overproduction or underproduction of hormones may cause emotional disturbances that lead to criminal behaviour. Testosterone has been linked to crimes such as murder and rape.
What did Ellis and Coantz find out about Testosterone linking to criminality?
Ellis and Coantz found that testosterone levels peak from 16 to early 20’s and this correlates with the highest crime rates in males
Outline the hormone changes women have used as a defence when charged with crimes
Pre-menstrual tension, Post-natal depression and lactation have all been accepted as partial defences on the basis that the hormones affected the defendants judgement, mood or self control
What gene causes the most crime?
Testosterone
What is the function of testosterone?
‘Makes males male’
Why do some people take additional testosterone?
Bodybuilding
What is the impact of injecting testosterone into your body?
Severe damage to their bodies eg life expectancy decreases, much more likely to die of suicide, accidents or heart attacks
Why does testosterone make men more likely to die of infectious diseases?
Testosterone suppresses the immune system making men more likely to die of diseases as their body cannot fight off parasites
How many more times more frequently do men commit murder compared to women?
10X as men try to remove opposition or to appeal strong to women
How are Nature and Nurture linked when considering crime?
You cannot disentangle them, you can change the environment but not the genes
Biochemical Explanations
Describe how blood sugar levels can have an impact on criminality
Low blood sugar can trigger aggressive reactions. Studies have shown links between low blood sugar and alcohol abuse. Drinking alcohol can induce hypoglycaemia and increase aggression. Alcohol consumption is linked to violent crimes.
What did Schoenthaler claim he could do to young offenders?
Schoenthaler claims that by lowering daily sucrose intake of young offenders he could reduce their level of antisocial behaviour
Describe how substance abuse can have an impact on criminality
Involves intake of drugs and other substances. Some are legal eg alcohol or medically prescribed, while others are illegal like cannabis or LSD. Saunders calculated that alcohol played a major role in about 1000 arrests a day. Cocaine and Crack are closely linked to violence. Cannabis and heroine tend to reduce aggression
What percentage of family violence cases involve alcohol according to Flancer?
Flancer estimated that 80% of family violence cases in the US involved alcohol
Describe how other substances can have an impact on criminality
Includes food additives, diet, allergens, vitamin defincies and lead pollution. They affect various biochemical processes in the Body and this can affect behaviour.
- Vitamin B deficiency has been linked to erratic and aggressive behaviour.
- Lead and synthetic food colouring Tartrazine has been linked with hyperactivity.
However, the link between such substances and criminality is not always clear
What is serotonin?
A hormone and Neurotransmitter
Why is it called the ‘happy chemical’?
It Is called this because it players a major role In regulating mood
What are low levels of serotonin linked with?
Depression
List the disorders that serotonin play a role in
Anxiety, OCD, PTSD, phobias and epilepsy
Which bodily functions does serotonin have a role in?
Apetite, digestion, bone health, sex and sleep
What is tryptophan ?
An amino acid present in most protein-rich foods like egg, nuts, seeds, cheese and poultry
Why is it tryptophan important?
It can help treat depression symptoms
