Biological Explanation of Crime and Anti Social Behaviour.

Question 1

What is Criminological Psychology ?

Answer 1

Criminological Psychology refers to the application of psychological knowledge to understand crime and anti- social behaviour. This includes what causes individual to commit a crime, behaviour in a courtroom with particular reference to juries and witnesses and treatment options for offenders to reduced of them committing a crime.

Question 2

Define crime ?

Answer 2

Crime is an act ( or omission of an act) that is against the law. Crime also implies punishment - or at least some treatment ( probation ) to reduce the likelihood of them returning to crime.

Question 3

Define anti-social behaviour ?

Answer 3

Anti-social behaviour is a common offence and refers to behaviour that affects other people negatively. The Crime and Disorder Act 1998 defines anti-social behaviour as acting in a manner that caused or was likely to cause harassment, alarm or distress. behaving ant-socially includes being drunk and disorderly, threatening behaviour, playing loud music at night and taking drugs.

Question 4

Describe the gender differences in Criminal and anti-social behaviour ?

Answer 4

Males are known to carry out more crimes than females. There is a significant difference between the number of males and females offenders. I the UK, the Ministry of justice published an analysis of recent data called statistics on women in the Criminal justice system (2013), this review found the approximately 80% of all offenders are male and 20% are female.

Question 5

What are the 4 biological explanations of crime and anti-social behaviour we study ?

Answer 5

1) Brain injury
2) the role of amygdala and aggression
3) XXY syndrome
4) Eysenck 5 dimensions of personality - PEN Personality.

Question 6

What does the term Brain Injury refer to ?

Answer 6

The term brain injury is given to any impact on brain structure that can affect its functioning. Brain injury can be categorised into acquired traumatic brain injury and non traumatic brain injury.

Question 7

What is an acquired traumatic brain injury ?

Answer 7

Acquired traumatic brain injury (ABI) is a brain injury as a result of an external force such as a blow to the head from an accident.

Question 8

What is a non traumatic brain injury ?

Answer 8

Non traumatic brain injuries are usually brain injuries that result from illness such as brain tumours and stroke.

Question 9

How are brain injuries studied and who typically studies them ?

Answer 9

Brian injuries are typically studied medically by neuroscientists who look at the biological working of the brain structure. This is generally carried out using scanning techniques such as MRI, PET and CAT scans. Brain injuries are also studied psychologically by neuropsychologists who look at the cognitive functionality of brain injured patients. Case studies of brain damaged patients are used.

Question 10

why is important we study brain injuries ?

Answer 10

Studying brain injuries enables an understanding about what parts of the brain manage cognitions and in turn behaviours. For example, if an area of the brain is injured it can impact upon the functionality of the behaviour associated with that area. This contributes greatly towards understanding what areas of the brain relate to control and management of behaviours.

Question 11

How do case studies of brain damaged patients provide supporting evidence for the link between brain injury and crime ?

Answer 11

Case studies of brain damaged patients dating back nearly 200 years have shown how anti-social behaviour can arise from frontal lobe injury. In these case studies, damage to the frontal lobe was linked to poor impulse control, sudden outburst of temper and lack of interpersonal sensitivity. This area of the brain can therefore, be associated with decision making and impulse control. One of the most famous of these early case studies is that of Phineas Gage.

Question 12

Describe the case study of Phineas Gage and it’s link to brain injury and crime ?

Answer 12

The case of Phineas Gage was the first documented case of a person who survived an acquired traumatic brain injury that affected their behaviour in a negative way. Phineas Gage worked as a railroad construction worker in America. Prior to the accident, Phineas was described as a likeable family man with an even temperament. Phineas accident occurred with an explosion causing an iron rod to passing through his skull and destroying the majority of his left frontal lobe. After his injury Phineas recovered physically however his personality changed as he went from a polite likeable family man to a rude irritable drunk. This provides evidence for the explanation of crime and anti-social behaviour through brain injury as after his accident Phineas Gage showed many similar characteristics of those who are likely to commit a crime.

Question 13

Who carried out a extensive review on case studies linked to the frontal lobe and crime and what did they find ?

Answer 13

Brower and Price (2001) carried out an extensive review on many case studies that had investigated the link between the frontal lobe damage and criminal behaviour. They concluded that frontal lobe injury is associated with increase impulsive aggression. However, they did not find clear evidence that showed that frontal lobe damage could predict violent crime. As they mention one study ( Labbatte et al 1997) of two cases of adults where there was an improvement in impulsive and anti-social behaviour after frontal lobe injury.

Question 14

What evidence from brain scanning provides support for the link between brain injury and crime ?

Answer 14

Grafman et al (1996) studied men that sustained brain injuries whilst fighting in the Vietnam War. He used brain scanning techniques and found those veterans with brain damage to the frontal lobe were more likely to be aggressive, getting into fight and arguments, than those with damage in other areas of the brain.

Question 15

What is more recent research supporting the link between brain injury and criminal and anti-social behaviour ?

Answer 15

Williams et al (2010) investigates whether there was any link between head injuries and criminal and anti-social behaviour. He found that :
• 60% of 196 prisoners they investigated had received some form of traumatic brain injury due to falling, car accidents or sporting activities.
• Adults with brain injury were relatively younger at entry into prison systems and reported higher rates of repeat offending than those without brain injury.
They concluded that the results suggest that these injuries affect the development of temperament, social judgement and the ability to control impulses. Brain injury may also contribute to the greater level of risk taking behaviour, making it more likely an individual may become involved in antisocial activity. Therefore, impairment in areas such as frontal lobe can contribute towards the development of criminality.

Question 16

What is the gender difference for Brain injury ?

Answer 16

Headway - The Brain Injury Association report that males are more prone to head injuries than females.

Question 17

How does Evolution explain gender difference in brain injuries ?

Answer 17

Wilson and Daly (1985) proposed status competition as a way of explaining the evolutionary advantage of male aggression and violence. Status competition means that males will participate in risky activities such as violence even if they involve the possibility of serious injury or death. By engaging in aggressive and risky behaviours they compete for higher status than other males, increasing their chances of winning a high value mate and therefore increasing their chances of successfully reproducing. This is because, they argued, females will be attracted to aggressive risk takers as such males are displaying willingness to take risks in competition for food etc. Such risky behaviour patterns put males more at risk for acquired traumatic brain injury.

Question 18

What are the strengths of brain injury as an explanation of criminal and anti-social behaviour ?

Answer 18

A strength of brain injury as an explanation of criminal behaviour is it can be seen that there is extensive reliable evidence from a variety of different types of studies linking brain injury and anti-social behaviour. This supporting evidence therefore provided the brain injury explanation of criminal behaviour with scientific credibility.

Additionally brain injury is a useful theory for explaining gender differences in criminal and anti-social behaviour. This is because more males experience brain injury than females and more males are involved in crime than females.

Question 19

What disproving evidence is there for the link of brain injury and criminal behaviour that limits this explanation.

Answer 19

A weakness of brain injury as an explanation as criminal behaviour is that there is evidence against this explanation. kreutzer (1991) studied 74 prisoners with brain injuries. Most of these arrests occurred after the consumption of alcohol or illegal substances. Kreutzer concluded that they were unable to prove or disprove a cause and effect link between traumatic brain injury and violence with substance abuse, traumatic brain injury and crime all interlinked.
Furthermore Labbatte et al (1997) was a case study of two adults where there was improvements in impulsive and anti-social behaviour after frontal lobe brain injury.

Question 20

What are the weaknesses of brain injury as an explanation for criminal and anti-social behaviour ?

Answer 20

A weakness of this explanation is that the research that underpins the theory is limited. With case studies of brain damaged patients often being dependent on one person or a small collection of people. This means the samples lack generalisability to the wider population of criminals. It should also be noted that much of the research on brain injury focuses on the link with aggression and violent crime, but not all crimes are violent e.g fraud. Once again reducing its generalisability.

Additionally research in this area has not established clear cause and effect links between brain injury and criminal behaviour. Whilst brain injury may make a person more impulsive and aggressive this does not mean they will become a violent criminal. Many variable are left uncontrolled in this field of research that could affect criminal behaviour. For example when considering the influence of brain injury in Williams et al (2010) research comorbidity must be taken into account as many offenders having s history of drug and alcohol abuse.

Furthermore the focus on brain injury as an explanation of criminal behaviour is, a reductionist way of explaining criminal behaviour. Criminal behaviour is likely to be the product of many interacting influences.

Question 21

What is the Limbic system ?

Answer 21

The limbic system is in the mid brain and is a collection of smaller brain organ structures which are responsible for initiating or controlling emotions.

Question 22

What is the Amygdala ?

Answer 22

The amygdala is a small almond like structure that sits within the limbic system. The amygdala is responsible for processing emotions such as happiness, anxiety, fear and aggression. When we are exposed to a threatening stimulus, our amygdala is activated and this results in an increase in arousal and emotions. This response in the brain activates responses to the stimuli through our behaviour and as a result of the amygdala being aroused a human response is to either take flight or fight and become aggressive towards the threat. The amygdala itself doesn’t produce aggression, it is connected to other parts of the brain that produce aggression. But it is necessary to initiate aggression of the flight response. Without it we wouldn’t experience the the emotional reaction associated with aggression. Additionally the amygdala has been linked to moral reasoning.

Question 23

How does a faulty amygdala link to criminal and anti-social behaviour ?

Answer 23

If the amygdala is not functioning correctly it may lead to a higher likelihood of criminal behaviour. This may be because :
• The threshold at which the activation of the amygdala occurs is too low - resulting in sudden outbursts of unprovoked aggression, leading to assult.
• The amygdala is malfunctioning so that anxiety and fear levels are low, may lead to high levels of risk taking behaviour that may result in criminal acts.

Question 24

What case study of brain damaged patients supports the explanation of aggression caused by the amygdala and its link to crime and how does it do so ?

Answer 24

The case study of Charles Whitman documents one of the first case studies where a criminal act was linked to the amygdala. Charles Whitman was an ex-marine who was studying engineering at the University of Texas. In the early morning hours of August 1st 1966, Whitman murdered his wife and mother in their homes. Later that day he brought a number of guns to the campus of the University of Texas and killed 14 people and injured 32 other in a mass shooting. Whitman was shot at the scene of the crimes. Following his death an autopsy was carried out and they found Whitman to have a cancerous brain tumour, approximately the size of a walnut, which was located in the limbic system and impacting the amygdala, thalamus and hypothalamus. It is believed that this brain tumour had significant effect upon his brain functioning which lead to this criminal behaviour. Although this isn’t demonstrated conclusively, this case study suggests the possible impact that the amygdala can have in criminal behaviour.

Question 25

Describe recent research that links the amygdala to criminal and anti-social behaviour.

Answer 25

Yang et al (2009) were interested in the link between smaller volume of the amygdala and anti-social behaviour. The researchers looked at 27 psychopathic people and compared them to 27 controls and used a structural MRI scanner to measure the volume of both amygdala in each participant. They found psychopathic people had lower volume on both amygdalae compared to the controls. On average they had 17.1% lower volume in the left amygdala and 18.9% less volume in the right amygdala. There was also a significant correlation between reduced volume of the amygdalae and high psychopathy scores. They concluded that, problems with the functioning of the amygdala is involved in criminal and antisocial behaviour.

Question 26

What are the strengths of the amygdala and aggression explanation of crime and anti-social behaviour ?

Answer 26

From the case study of Charles Whitman and the more recent research by Raine et al (1997) and Yang et al (2009) it can be seen that there is scientific evidence of the link between the amygdala and criminal and anti-social behaviour. As the research methods used to investigate this link have been objective analysis techniques such as brain scans therefore; providing the study with scientific credibility.

Question 27

What are weaknesses of the amygdala and aggression explanation of of crime and anti-social behaviour ?

Answer 27

This explanation has limitations as the research that supports the theory is largely based upon case studies such as Charles Whitman. Case studies like these lack generalisability to the wider target population of criminals as they are based upon either one person or a very small group of people with a unique characteristic.

Additionally research into the amygdala does not explain the gender differences in criminal and anti-social behaviour. This limits the explanations usefulness.

Furthermore the research on the amygdala is reductionist since over simplifies the complexity of criminal behaviour down to one structure in the limbic system. This is problematic for two reasons firstly it is clear that other areas of the brain can be damaged or dysfunctional leading to violence and anti-social behaviour. Secondly, it overlooks social factors (nurture) that can contribute to criminal behaviour.

Question 28

What’s are chromosomes ?

Answer 28

Chromosomes are long cooled molecules of DNA that are carried by the cells in our body contained in the nucleus of every cell.

Question 29

What is DNA ?

Answer 29

DNA molecules are divided up into regions called genes. So DNA carries the genetic code that determine the characteristics of living organisms. DNA consists of two strands coiled into a double helix, other than identical twins everyone has unique DNA.

Question 30

What are genes ?

Answer 30

A gene is a section of DNA that carry codes for a specific proteins. DNA is hereditary and may be copied and passed on to the next generation. Each gene holds information to build and maintain cells and to pass on genetic traits to offspring

Question 31

How many pairs of chromosomes do you humans have and which of these are related to someone’s gender ?

Answer 31

Humans have 23 pairs of chromosomes, giving a total of 46 chromosomes. The 23rd pair consists of the sex chromosomes, which are either X or Y. An XX pair will result in a baby girl being born and an XY pair will result in baby boy being born.

Question 32

What is XYY syndrome ?

Answer 32

In the early 1960s the XYY syndrome was discovered. This syndrome relates to a chromosomal abnormality and occurs when males has an extra Y chromosome on the 23rd chromosome pair instead of the normal XY. Therefore the individual has a total of 47 chromosomes. This occurs in 1 of 1000 males. It is not an inherited condition but occurs randomly at the time of contraception.

Question 33

What are the 7 potential symptoms males with XYY syndrome can experience ?

Answer 33

1) taller than normal
2) severe acne
3) reduced intelligence
4) learning difficulties
5) developmental delays in speech and language
6) difficulties in the development of walking
7) behavioural and emotional difficulties.

Question 34

What early research was conducted on the XYY syndrome ?

Answer 34

When the syndrome was discovered, researchers linked it to criminal behaviour from observation of the criminal population. For example Jacobs et al (1965) suggested that men with XYY syndrome were more aggressive than XY men and found that there was an over representation of XYY men in the prison population with 15 XYY men for every 1000 prisoners.

Furthermore in 1968 Daniel Hugon murdered a prostitute in a Paris hotel. He surrendered to the authorities with a confession filled with remorse. On the day of the trial Hugon attempted suicide, this lead to an extensive physical and mental examinations before the trail commence. Upon these examinations it was discovered Hugon had XYY syndrome. This was used by the defence in the court case to imply his behaviour was pre-determined.

Question 35

What study that used brain scanning supports the explanation of criminal and anti social behaviour through the amygdala ?

Answer 35

Raine et al (1997) study on brain abnormalities in murderers indicated by PET scans.

Question 36

What was the aim of Raine et al study ?

Answer 36

Raine et al wanted to find out which brain areas are dysfunctional in violent offenders using PET scans. They hypothesised that participants pleading NGRI would show brain dysfunctions in areas of the brain associated with violence.

Question 37

What was the sample of Raine et al study ?

Answer 37

There were two groups in this study with 41 participants (39 males and 2 females) in each group.
The experiemental group consisted of 41 criminals convicted of manslaughter or murder in the American state of California who were being tested to gain evidence to support their plead in court of not guilty by reason of insanity (NGRI). 6 of these suffered from schizophrenia, 23 had experienced brain damage or a head injury, 3 were substance abusers, 2 had epilepsy and 2 had been diagnosed with paranoid personality disorder. participants in the experimental group were labeled as seriously violent individuals.
The controls group was a matched pair of the experimental group on a number of variables such as age, gender and psychiatric illnesses. the control group were further screened on their mental and physical health. They underwent a physical examination, the researchers assess their medial history and performed a psychiatric interview.

Question 38

What was Raine et al research method ?

Answer 38

laboratory experiment as well as a quasi or natural experiment because the researchers did not have total control over the independent variable as it was not manipulated by the researchers themselves. the participant groups are pre-existing and so the participates can not be randomly placed into conditions of the experiment.

Question 39

What was the research design used in Raine et al study ?

Answer 39

matched pairs design.

Question 40

What was the independent variable and dependant variable in Raine et al study ?

Answer 40

The independent variable was whether the participant had committed murder/manslaughter or not.
The dependent variable was the result of the PET scan.

Question 41

What was the procedure of Raine et al study ?

Answer 41

Participants were required to perform the continuous performance task involving them staring at a screen whilst various blurred shapes appeared. The participants was to press a button when a particular symbol appeared, thus requiring constant attention to the screen. They did this for 10 minutes as a practice trial. A radioactive glucose tracer (flurodeoxyglocose) was then injected into the participant. After this participants were required to complete the same continuous performance task for 32 minutes whilst their brains were scanned using a PET scanner in order to determine the glucose metabolic rate throughout the brain which determines the level of activity in various regions of the brain.

Question 42

What are the results of Raine et al study relating to the amygdala ?

Answer 42

There were abnormal asymmetrical levels of activity within the limbic system in the experimental group compared to the control group. With higher activity in the right hemisphere of the amygdala and lower activity in the left hemisphere compared to the control group.

Question 43

What are the conclusions of Raine et al Study relating to the amygdala ?

Answer 43

Reduced activity in certain areas of the brain together with aboral asymmetries of activity in structures of the limbic system could predispose a person towards violent behaviour. for example the abnormal functioning of the amygdala which is responsible for emotional processing results in murders being fearless. this fearlessness could result in the increase chance of acting violent.

Question 44

Describe Alice Theilgaard’s research into genetics and criminal behaviour ?

Answer 44

Alice Theilgaard (1984) wanted to see if there was a particular gene that could be responsible for criminal behaviour and investigate the XYY syndrome. Theilgaard took blood samples from over 30,000 males born in the 1940’s. from the initial blood tests, two chromosomal abnormalities were identified, 16 had XXY and 12 had XYY chromosomal abnormality. Following these test all of the men were interviewed by a social worker about their background and their criminal involvement. They were also given intelligence test and personality test to measure their aggression. The results showed that those with the XYY syndrome were found to have slightly lower intellegence and tended to be more aggressive than normal. This could be a link to suggest there is evidence for a criminal gene if aggression is a sign of criminality ( however not all criminals are aggressive and not all aggression is criminal). In conclusion Theilgaard found no conclusive evidence for a criminal gene.

Question 45

What is recent evidence that disproves the link between XYY syndrome and crime ?

Answer 45

Re and Birkhoff (2015) carried out a review study meaning they drew together a lot evidence from over the previous 50 years relating to XYY syndrome and crime. studies tended to show no relationship between XYY syndrome and criminal behaviour. Even the they did find a study with a link between XYY syndrome and crime, it was often accompanied by by an unfavourable environment like a prison or rehabilitation centres. They emphasised that XYY syndrome was linked to poor environmental and social factors rather than directly to crime. for example, they report a study by Stockholm et al (2012) of 161 XYY male criminals aged between 15-70 years old. The apparent link between XYY syndrome and crime in this sample disappeared when researchers controlled for social and economic variables. Re and Birkhoff concluded that analysis of the studies in their review showyvthat there is no statistical evidence that XYY men are predisposed to aggressive and deviant crime.

Question 46

What is a strength of the XYY syndrome as an explanation of criminal and anti-social behaviour ?

Answer 46

a strength of the XYY syndrome as an explanation of criminal ad ant-social behaviour has supporting evidence for example Jacobs et al (1965) giving the study scientific credibility.

Question 47

What are weaknesses of the XYY syndrome as an explanation of criminal and anti-social behaviour ?

Answer 47

To carry out genetic research among criminal population requires skilled staff and the resource use is intensive. Therefore it is not practical to determine whether all male offenders have the XYY syndrome. It would be extremely costly and invasive. Therefore the true extent of the prevalence of XYY syndrome in criminals will probably take take sometime to be fully understood.

Also their is disproving evidence as theilgaard indicated there was a very small presence of XYY in some criminals and Re Birkhoff concluded that the non statistical evidence that an XYY man is predisposed to aggressive and deviant behaviour. this suggests it cannot be the only reason for criminal behaviour in men. other factors must be involved or we would expect to see a much higher incidence of XYY in the criminal population. Therefore explanation can be argued to be reductionist as it is trying to explain criminality in terms of one genetic pattern and ignores environmental influences on criminality.

in addition, women also carry out crimes and will not have the XYY syndrome therefore the explanation has limitations in that it cannot fully explain all cases of criminal behaviour. The XYY syndrome is specific only to males.

Furthermore this explanation is deterministic, in that it implies that people commit crimes or reasons that are beyond their control so does not appear to allow for the possibility that criminal behaviour is a free choice. If criminality is caused by a genetic factors then it would invalidate the criminal justice system as we know it as there would be no need for trial process.

Question 48

what are the 3 dimensions of personality ?

Answer 48

1) Extraversion to Introversion
2) Neuroticism to Stability
3) Psychoticism

Question 49

What is personality ?

Answer 49

Personality is stable characteristics ( traits ) that underlie consistencies in the way behaviour over time and in different situations. We all have different personalities which make us the individuals we are. Our personality explains our interests, hobbies, how we interact with other, how we respond to situations and our overall outlook of life.

Question 50

Define Extraversion ?

Answer 50

Extraversion is behaviour that is typically outgoing, sociable and active. extraverts are individuals want excitement and may become bored easy.

Question 51

Define Introversion ?

Answer 51

Introversion is behaviour that is typically reserved and reflective. introverts are more likely to prefer solidarity to social activities.

Question 52

Define Neuroticism ?

Answer 52

Neuroticism is emotional instability associated with anxiety, fear, depression and envy.

Question 53

Define Stability ?

Answer 53

Stability is the traits of emotionally calm, unreactive and unworried.

Question 54

Define Psychoticism ?

Answer 54

Psychotics are individual who lacks empathy and are aggressive, impersonal and cold.

Question 55

How is personality measured ?

Answer 55

Personality is measured through self report in the form of psychometric test. Psychometric tests are questionnaires that allow the researchers to quantify a psychological variable. Hans Eysenck developed and used the Eysenck Personality Inventory (EPI) which is made up of a series of fixed response (closed) questions to measure personality

Question 56

Why can the validity of psychometric tests for personality like the Eysenck Personality Inventory (EPI) be limited.

Answer 56

the validity of the EPI is limited because of:

1) social desirability as people might prefer to be seen to have particular personality traits different to their own so may not answer truthfully.
2) demand characteristics as individuals know they are being tested and may alter their response or behaviour to suite what they believe the researchers want.
3) reductionist as personality is a complex human variable and psychometric test like the Eysenck Personality Inventory reduce this to a set of score.

Question 57

What did Eysenck argue in terms of personality ?

Answer 57

Hans Eysenck proposed that biological components determine your personality and that differences in people’s personailty could be reduced to to the three dimensions including why some people commit crimes and others do not.

Question 58

What is PEN personaility ?

Answer 58

Eysenck proposed that the three personality traits of psychoticism, Extraversion and Neuroticism could be applied to criminality. This was referred to as the PEN personality.

Question 59

What is the Arousal theory relating to PEN personality ?

Answer 59

in 1990 Eysenck proposed that Arousal theory provided a biological explanation of PEN personality. The Arousal theory proposes that individuals are motivated to act in ways that maintain optimum levels of physiological arousal. When arousal levels fell below/ above an individuals optimal levels the individual would engage in behaviours to increase/decrease arousal

Question 60

What is the biological link to Psychoticism ?

Answer 60

Eysenck liked psychoticism to hormones particularly testosterone and enzymes such as MAO. as people who show a psychotic episode have increased testosterone levels and low MAO levels.

Question 61

What is the biological link to Extraversion.

Answer 61

Eysenck explained extraversion in terms of cortical arousal via the ascending reticular activation system (ARAS) within the brain. Activity in the ascending reticular activation system stimulates the cerebral cortex which in turn leads to higher cortical arousal. Extraverts have lower levels of activity than introverts so they are less cortically aroused than introverts. As extraverts are characterised by underachieve ARAS they require greater amounts of external stimulation explaining why they are more outgoing and part take in risk taking behaviour.

Question 62

What is the biological link to Neuroticism ?

Answer 62

Eysenck explained neuroticism in terms of activation thresholds in the sympathetic nervous system which is linked to the limbic system. The limbic system is where emotional states such as aggression and fear are regulated as well as being responsible for the flight or fight response. Neurotic individuals have greater activation levels and lower thresholds within the limbic system; causing them to become easily upset at minor stresses.

Question 63

What was the aim of Eysenck supporting evidence for his own claims ?

Answer 63

Eysenck et al (1977) investigated the link between personality and criminal behaviour. The aim of his study was to attempt to link certain criminal behaviour to personality traits. The personality traits measured in the study was Psychoticism, Extraversion and Neuroticism (PEN personality)

Question 64

What was the sample of Eysenck supporting evidence for his own claims ?

Answer 64

Eysenck recruited 156 prisoners aged 18-38 years old as his participants. they were divided into five groups based on the crimes they committed.

1) violent crimes
2) property crimes
3) confident crimes e.g. fraud
4) Inadequate - minor crimes with a sentence of less that 18 months.
5) Residual - those criminals who didn’t fit into the above categories.

Question 65

What was the procedure of Eysenck supporting evidence for his own claims ?

Answer 65

All 156 prisoners were tested on the Eysenck Personality Questionnaire (EPQ) and a variety of physiological measures including ECG and skin conductance.

Question 66

What are the key results and conclusions of Eysenck supporting evidence for his own claims ?

Answer 66

Eysenck claims that it is possible to classify offenders by personality types with those who committed confidence crimes having low score in Psychoticism compared to other categories. Additionally, violent and property offenders had low score in neuroticism whereas inadequate and residuals offenders had high score in neuroticism. Violent and residual offenders had high score in extraversion competed to inadequate and property offenders having low score in extraversion.
Overall Eysenck argues that certain personality traits can be liked to criminal behaviour.

Question 67

What other supporting evidence is there for the link between personality and criminal behaviour ?

Answer 67

Ruston et al (1981) investigated delinquents and showed clear support for a relationship between high delinquency scores and high scores on both psychoticism and extraversion.

Boduszek (2013) investigated personality traits in predicting violent offending within a sample of repeating inmates from a high security prison in Ireland.
They found that higher levels of extraversion predicted a greater level of committing a violent act.

Question 68

What evidence supports the PEN personality explanation shows a gender difference in criminal and anti-social behaviour ?

Answer 68

Lynn and Martin (1997) assessed the PEN personality in 37 countries and found that
1) women scored higher on neuroticism in all the countries.
2) men had higher psychoticism in 34 countries.
3) men had higher extraversion scores in 30 countries.
these findings indicate that there are gender differences in personality. Also, considering that psychoticism and extraversion featured more in males offenders, personality offers a potential explanation as why males carry out more crimes than females.

Question 69

What are the strengths of personality as an explanation for criminal and anti-social behaviour ?

Answer 69

the PEN personality theory has its basis in biological causes which can be directly tested. This has led the theory to gain respect due to its scientific underpinning.

another strength of Eysenck PEN personality theory of crime is it also caters for individual differences and highlights the individual variation that can occur between everyone. It can also explain gender differences that are seen in criminal behaviour as shown by Lynn and Martin research.

furthermore the data Eysenck and others collected in this field of research tends to use the EPI. the Eysenck personality Inventory has been found to be reliable in measuring personality traits. For example Tiwari et al (2012) used a Hindi form of the EPI on 78 men and 124 women in India. They reported that the questionnaire has internal consistency because it reliably measured neuroticism and extraversion.

Question 70

What are the weaknesses of personality as an explanation for criminal and anti-social behaviour ?

Answer 70

A weakness of this explanation is that there is some inconsistiencies in the results as Broduszek (2013) investigated personality traits in predicting violent offending within a sample of repeating inmates from a high security prison in Ireland. they found that higher levels of extraversion predicted a greater level of committing a violent act. In contrast Farrington (1982) found that extraversion was less associated with criminal conviction than the two other personality traits.

Personality research is frequently based on self-report. This reduces the validity of the findings as the accuracy of the information gathered may be poor due factors such as response bias and socially desirable answers.

Another weakness is that the theory is deterministic as Eysenck believes that personality is determined by biology and therefore criminal behaviour, in certain people is inevitable. This means criminals do not choose their behaviour patterns.

Lastly this theory can be seen to be reductionist as it is too simplistic and fails to consider a how persons reactions or behaviour may differ depending on the situation. It doesn’t consider other potential biological causes either such as brain injury or genetics.