Studies for Paper 2

Question 1

Yerkes-Dodson Law (1908) - stress and arousal

Answer 1

any type of performance, including cognitive performance or memory, can become impaired if we get too stressed - this is known as the Yerkes-Dodson Law. An optimum level of stress is good. However, too little arousal, i.e., being too relaxed might result in little attention being paid and too much arousal might result in heightened levels of anxiety or stress affecting performance.

Question 2

Loftus (1974) - eye-witness testimony

Answer 2

many psychologists have questioned the effectiveness of eyewitness testimony. however, it is hugely influential, for instance, in a famous study carried out by Loftus participants were asked to judge the guilt or innocence of a man accused of robbing a grocer’s and murdering the owner and his 5 year old granddaughter. on the evidence presented only 9 out of 50 students considered the defendant guilty. However, when other students were presented with the same case, but also an eyewitness to the event testifying that the defendant had committed the crime 36 out of 50 judged him to be guilty.

Question 3

Valentine and Mesout (2009) - eyewitness testimony and stress

Answer 3

studies into the effects of arousal on EWT have generated mixed results. e.g., Valentine and Mesout London Dungeon study found that heightened anxiety resulted in worse recall of the ‘scary’ person: being highly anxious reduces the accuracy of eyewitnesses in identifying perpetrators. this was a field study so was therefore higher in ecological validity than a laboratory experiment.

Question 4

Loftus and Palmer (1974) - post-event information

Answer 4

• experiment 1: 45 participants were shown 7 video clips of different car accidents, in different orders, and asked to estimate the speed of the cars. all the participants received the same questions, but 1 critical question was changed for each set of 9 participants. experiment 2: this time the critical question was: did you see any broken glass?
• experiment 1: concluded that either the verb used in the critical question altered the participants’ memory of the film or the participants did not know the answer so relied on the verb to make their judgement. experiment 2: changing the verb used in the critical question to ‘smashed’ did have a significant effect on participants’ recall, they were more likely to recall broken glass when there was none.

Question 5

Neisser and Harsch (1992) - flashbulb memories

Answer 5

asked students to report hoe they learned about the Challenger Space Shuttle disaster 1 day after the event and 3 years after the event. when asked 3 years later to recount how they learned of the disaster, no one produced an entirely accurate report compared to the one produced a day later and over 1 in 3 produced a completely inaccurate report even though they thought it to be very accurate.

Question 6

Sanders (1984) - clothing

Answer 6

witnesses pay more attention to a suspect’s clothing than to more stable characteristics, such as height and facial features. in Sander’s experiment, participants saw a video of a crime in which the criminal wore glasses and a t-shirt. afterwards, they were asked to select the criminal in an identification parade and were more likely to select a person wearing glasses and a t-shirt.

Question 7

Ihlebaek et al (2003) - methodological issues related to EWT

Answer 7

conducted a laboratory and field experiment, a live staged robbery and video footage of the same robbery. participants who watched the video footage of the robbery recalled more details with greater accuracy than the live robbery. however, both groups made the same number of errors.

Question 8

Pickel (1998) - EWT

Answer 8

• experiment 1: 230 undergraduate students in a US university were shown a 2 minute video reconstruction of an incident set in a hair salon. the items were categorised according to their unusualness and threat: a pair of scissors, a handgun, a wallet, a raw chicken and empty. experiment 2: exactly the same procedure but this time the context was an electrical repair shop.
• experiment 1: the handgun and raw chicken produced the poorest recall of the man. the scissors and the wallet had least effect on recall. the raw chicken and the handgun are both high unusualness in the context of a hair salon, so it must be unusualness that leads to poor recall, rather than threat. experiment 2: these findings replicate those of experiment 1

Question 9

Yuille and Cutshall (1986) - EWT

Answer 9

• the incident involved a shooting which occurred on a spring morning outside a gun shop in full view of several witnesses in Vancouver, Canada. 21 of the witnesses were interviewed by police shortly after the event and 13 of them agreed to take part in a research interview 4 to 5 months later. participants also self-rated the stress they felt at the time of the incident on a 7-point scale.
• researchers noted that witnesses were very accurate and detailed in both the police and research interviews. witnesses that were central to the event gave more details than did the peripheral witnesses, but there was no overall differences in accuracy between the 2 groups. significantly, the wording of the misleading questions had no effect: those who were most deeply distressed by the incident, e.g., suffered nightmares, i.e., those whose memories might be expected to be most distorted by the stress of the experience were the most accurate of the witnesses.

Question 10

Yarmey (2004) - EWT

Answer 10

• the participants were given a 16 question recall test that included questions about the physical characteristics and clothing of the female target. participants were then given a set of 6 photographs, showing women similar to the female target, and asked to pick out from the 6 the female target. this standard procedure was followed with all the participants, although there were changes to this procedure to test different variables, including: preparation (some participants were told to be ready for a memory test by the female target and some were not), retention time span (some participants were asked to recall immediately after encountering the female target, some 2 minutes later and some 4 hours later), and line-up (some participants saw the target female in the photographic line-up whilst others did not)
• eyewitness photo fit identification tends to be quite poor. even when the witness is primed to pay attention this does not seem to improve photo identification. students significantly overestimated how many eyewitness participants would be able to identify the target correctly. this is important because there is no reason to assume why the undergraduate students would think and behave differently to anyone else with regard to this, i.e., members of juries also put great faith in eyewitness testimonies, perhaps misguidedly in some cases.

Question 11

Pardini et al (2014) - amygdala

Answer 11

Psychopaths, as well as those with higher than average levels of aggression, have been found to have smaller amygdalae than controls. This study noted that psychopathic personality traits and higher than normal levels of aggression were apparent from childhood. Up to 3 years later, individuals with smaller amygdalae were 3 times more likely to exhibit aggression, violence and psychopathic tendencies than those with larger amygdalae

Question 12

James Fallon - amygdala

Answer 12

not everyone with a smaller amygdala acts in an excessively aggressive, psychopathic way and not everyone who acts aggressively or without emotion is a psychopath, e.g., neurologist James Fallon in 2006 identified his own brain as a psychopathic brain, yet he does not exhibit criminal or anti-social behaviour or tendencies.

Question 13

Cannon and Britton (1925) - amygdala

Answer 13

sham rage – coined this term to describe an emotional state in animals. They severed the neural connections to the cortex of cats, creating ‘decorticate cats’. When provoked, these cats demonstrated emotional behaviour associated with rage and aggression, e.g., erect fur, growling and bared teeth. This behaviour was referred to as ‘sham rage’ because it occurred without the cognitive influence or inhibitory influence of the cerebral cortex. It is now known that the source of this ‘rage’ comes from a temporal area of the brain: the amygdala. If this area is stimulated aggression is displayed, however, when this area is ablated, i.e., removed or destroyed, animals become much more placid. Research like this on animals has led to the acceptance that the amygdala plays an important role in the production of hostile or aggressive behaviour.

Question 14

Narabayashi et al (1963) - amygdala

Answer 14

carried out psychosurgery on human participants with aggressive behaviour, severing their amygdala from the rest of the limbic system, resulting in a mood-stabilising effect in the majority of patients over time.

Question 15

Raine et al (1997) - amygdala

Answer 15

study – showed that in a study of 41 convicted murderers, there was lower levels of activity in the PFC of the murderers compared to the control group, and differences in the functioning of the limbic system in the brain scans of the impulsive murderers, i.e., more aggressive and reduced ability to control aggressive impulses. This study showed significant differences in the brain structure of murderers compared to non-murderers, especially in the functioning of the amygdala. Results of this study showed lower levels of glucose metabolism in the prefrontal cortex or the murderers’ brains compared to the controls – this area of the brain is linked to impulse control or impulsivity. there were also significant differences in the functioning of the amygdala – linked to emotional responses or behaviour – and the hippocampus – linked to memory and learned behaviour. Abnormal functioning in these areas could help to explain why the murderers committed murder

Question 16

Glenn et al (2009) - amygdala

Answer 16

studied the neural circuitry underpinning amygdala functioning, not just size of the amygdala, using fMRI scanning. Psychopaths tended to have reduced amygdala functioning during moral decision-making, suggesting deficits in brain regions linked to moral reasoning, so psychopaths would worry less about causing pain to others.

Question 17

Robert Hare - amygdala

Answer 17

is a psychologist who is an authority on psychopaths and has developed a psychopath checklist or scale, his book, Snakes in suits: When psychopaths go to work – Babiak and Hare (2006), demonstrates how psychopaths are not just found among the criminal population

Question 18

the case study of Phineas Gage - brain injury

Answer 18

a 25 year old railway worker who, in 1848, experienced a horrific industrial accident that severely damaged his prefrontal cortex. His language and intellectual capabilities and movement were entirely unaffected by his brain injury. However, his personality underwent a significant change.

Question 19

Williams et al (2010) - brain injury

Answer 19

found 60% of the 196 prisoners they investigated had some form of traumatic brain injury, e.g., falling, sports head injury, car accidents. These adults tended to enter the prison system at a younger age than the non-trauma prisoners and had higher rates of recidivism. This study also suggested that these brain injuries affected temperance, i.e., ability to abstain from alcohol or drugs, social judgement and impulse control. these brain injuries may lead to greater risk taking behaviour, therefore, increasing the likelihood of engaging in anti-social or criminal behaviours. Williams et al concluded that impairment in the brain regions affected by the trauma could have contributed to criminality.

Question 20

Kreutzer et al (1991) - brain injury

Answer 20

unable to categorically prove or disprove a causal connection between traumatic brain injury and violence. Their investigation of 74 patients found that 20% had been arrested pre-injury and 10% post-injury. Most arrests occurred after the use of alcohol or other drugs, suggesting this was a key mediating factor. The researchers concluded that criminal behaviour might be the result of post-injury changes, including poor judgement. substance misuse, traumatic brain injury and crime were interconnected but the evidence for a causal connection between brain injury and crime was not present. Instead, the study suggested that substance abuse, which was most common among those younger than 35 years old, led to issues with the criminal justice system and traumatic brain injury. in subsequent research, Kreutzer et al (1995) concluded that without the presence of a substance abuse history, traumatic brain injury was not a risk factor for criminal behaviour.

Question 21

Signorielli (1989) - key question

Answer 21

found that 72% of characters with a mental illness depicted in prime-time TV were violent. Other studies found them to be unemployable or if employed, failing at work.

Question 22

Granello and Pauley (2000) - key question

Answer 22

found that intolerant attitudes towards those with mental health disorders were significantly and positively correlated with the amount of TV watched – correlations and cause and effect. TV viewing may be linked to other causal factors, lower socio-economic status, or educational ability, higher RWA ect.

Question 23

Lopex Levers (2001) - key question

Answer 23

in a content analysis of 50 years of Hollywood films and their presentation of mental illness, found that those with MHDs were often portrayed as passive, pathetic or comical, most frequently as dangerous – requiring restraints or invasive procedures. This portrayal does not reflect the reality of mental illness, rather a lazy, stereotypical view of mental illness used in film iconography.

Question 24

Bandura - key question

Answer 24

has developed social learning theory and shown how we model significant others and are influenced by media images, so negative stereotypes of mental illness, associating it with violence and crime, might influence how we react to people with mental disorders, possibly leading to discrimination and prejudice towards those with mental disorders.

Question 25

Bandura (1961) - key question

Answer 25

if a child is exposed to an aggressive model, it is likely that they will imitate their behaviour. Boys are more likely to imitate the same sex role model, more so than girls. Observation and imitation can explain how we learn certain behaviours without obvious reinforcement. We have a tendency to imitate same-sex models more.

Question 26

Bastian et al (2012) - key question

Answer 26

playing violent video games, unlike playing non-violent video games, does seem to lower someone’s perceptions of their own humanity – this was found in both studies. Playing violent video games makes us feel less human. When engaged in acts of violence against an opponent in the same violent game, our view of their humanness is also reduced, more so than if the opponent is in a non-violent video game. However, when the ‘other’ is a co-player, as in study 2, this does not lower their humanity in our eyes – the co-player is supporting the goals of the player, so might not be seen in the same dehumanised light.

Question 27

Brown and Bradley (2002) - key question

Answer 27

Research by Brown and Bradley (2002) in the US suggests that 25% of people with a MHD do not seek treatment and they suggest that stigma is a primary cause of this

Question 28

Goffman (1968) - key question

Answer 28

maintains that labelling someone as mentally ill stigmatises them, and that the stigma of mental illness remains long after the individual has recovered from the mental disorder.

Question 29

Scheff (1966) - key question

Answer 29

argues that a process similar to self-fulfilling prophecy occurs when someone is labelled as mentally ill. The individual may behave according to the diagnosis, especially since there are often rewards associated with adopting the role of mental illness and punishments for trying to escape from it, e.g., abdication of responsibility, stigma attached to not conforming to authority or expert figures.

Question 30

Wahl (2000) - key question

Answer 30

in a content analysis of articles related to OCD, Wahl (2000) found them to be mostly accurate, although some did link OCD with stalking behaviour inaccurately.

Question 31

Rosenhan’s classic study (1973) - key question

Answer 31

shows how behaviour is often judged within a particular context.

Question 32

Thomas Szasz (1974) - key question

Answer 32

argues that classification involves the inappropriate ‘medicalisation’ of psychological distress. In his famous work, The Myth of Mental Illness, Szasz argues that mental illness is better viewed as a problem in living, that is expressed socially. Labelling the individual ‘mentally ill’ is a form of social control by those invested with undisputed authority, i.e., the medical profession and it undermines personal responsibility.

Question 33

R. D. Laing - key question

Answer 33

famously suggested that mental illness was a fairly ‘rational’ response to the sense of alienation felt by many due to the intense pressure of family life and society: people are obsessed with maintaining the ‘status quo’ and strive to maintain their own definition of reality. “Mental illness need not be breakdown… it may also be breakthrough”. He was writing in the 1960s.

Question 34

Tartakovsky (2009) - key question

Answer 34

in a review of the depiction of MHDs for the APA it was said that the media portrays depression as a chemical imbalance, along with other types of MHDs. In some respects this might be accurate and positive, i.e., it implies the individual has no control over their condition, as it is a chemical imbalance in the brain which they cannot help. However, this may also serve to oversimplify MHDs.

Question 35

Penn et al (2003) - key question

Answer 35

some research suggests that giving people a medical cause for a MHD, such as schizophrenia, will reduce the blame associated with the disorder but does not change the prejudice linked to it, such as unpredictability and danger, in fact it might make people more likely to avoid those with the disorder in the future, as there is a sense that the schizophrenic individual will not be able to control their potentially dangerous thoughts and behaviour.

Question 36

Goldman et al (1996) - neurotransmitters and hormones

Answer 36

increased activity of serotonin synapses inhibits aggression, whereas low levels of serotonin will increase aggression.

Question 37

Valzelli (1973) - neurotransmitters and hormones

Answer 37

found that 4 weeks of social isolation in mice induced a drop in serotonin turnover in the brains of male rats – turnover is the amount of release and reuptake or resynthesis of a NT by presynaptic neurones. That is, a brain with low serotonin turnover may produce normal amount of serotonin, but the neurones fail to release it and resynthesise new serotonin to take its place. Valzelli found that social isolation lowered the mouse’s serotonin turnover and induced increased aggressive behaviour towards other males. 2 male mice with low serotonin turnover always fought. Mice with the lowest serotonin turnover fought the most. However, social isolation does not decrease serotonin turnover in female mice and does not make female mice more aggressive.

Question 38

Maes et al (1995) - neurotransmitters and hormones

Answer 38

The impact of low serotonin turnover is illustrated by a study in Belgium – which found that suicide rates were highest in spring, when serotonin turnover was lowest, and lowest in autumn and winter, when serotonin turnover was highest.

Question 39

Roy et al (1989) - neurotransmitters and hormones

Answer 39

a study of people who had survived suicide attempts found that low serotonin turnover predicted additional suicide attempts within the next 5 years.

Question 40

Virkkunen et al (1987) - neurotransmitters and hormones

Answer 40

studies with humans have shown that people with a history of violent behaviour tend to have lower than normal serotonin turnover, including people convicted or arson and other violent crimes. The same is true for people who commit or attempt suicide by violent means – Brown et al (1982).

Question 41

Lavine (1997) - neurotransmitters and hormones

Answer 41

found that an increase in dopamine levels through the use of amphetamines (‘speed’) was associated with an increase in aggressive behaviour, suggesting that higher levels of dopamine correlate with higher levels of aggression.

Question 42

Cleare and Bond (1997) - neurotransmitters and hormones

Answer 42

found that even in males with no history of psychiatric problems, low serotonin levels correlate with levels of aggression and hostility

Question 42

Cleare and Bond (1997) - neurotransmitters and hormones

Answer 42

found that even in males with no history of psychiatric problems, low serotonin levels correlate with levels of aggression and hostility

Question 43

Couppis and Kennedy (2008) - neurotransmitters and hormones

Answer 43

found that dopamine levels in mice would increase and act as a reward during an aggressive act.

Question 44

Beaver et al (2008) - neurotransmitters and hormones

Answer 44

Research has shown that individuals using anabolic steroids – a synthetic or man-made form of testosterone used to promote muscle growth and strength in users – are more likely to engage in violent acts, so called ‘roid rage’.

Question 45

Skarberg (2010) - neurotransmitters and hormones

Answer 45

men who use anabolic steroids, which are known to increase testosterone levels, are more likely to be involved in violent crime.

Question 46

Ellis (2000) - neurotransmitters and hormones

Answer 46

In 11 studies examining the relationship between blood and saliva testosterone levels and involvement in criminal activity, all 11 showed a positive but modest correlation in testosterone-related offenses, but note the small sample size.

Question 47

Dabbs et al (1995) - neurotransmitters and hormones

Answer 47

took saliva samples of adult male prisoners to test for levels of testosterone and found that those with higher levels of testosterone had a history of violent crime, whereas those with lower levels of testosterone had committed only non-violent crimes. This study also found that individuals with higher testosterone levels were more likely to be involved in direct confrontations with others while in prison and generally broke more prison rules.

Question 48

Soler et al (2000) - neurotransmitters and hormones

Answer 48

a study into domestic violence found that male offenders had higher levels of testosterone than males with no history of domestic violence.

Question 49

Albert et al (1986) - neurotransmitters and hormones

Answer 49

Animals studies have shown a reduction in aggressive behaviours following castration and also fewer attempts to display social dominance among rats that have been castrated.

Question 50

Hans Eysenck - personality

Answer 50

carried out extensive research into the personality traits of an individual, i.e., the enduring characteristics that make us who we are and influence our decisions and behaviour. These traits are thought to be relatively fixed and change little through our lifetime. Eysenck believed that personality was biologically determined. Hans Eysenck developed a theory of personality that is biologically determined. He argues that there are 2 dimensions to personality: extravert (E)-introvert (I), neurotic (N)-stable (S). He later added a 3rd: psychotic (P)-normal. These dimensions are continuums, i.e., most people will lie somewhere in the middle between being an extravert and an introvert: an extravert will have a strong need for excitement, be reliable, reflective, unaggressive and place high value on moral and ethical standards. the neurotic-stable dimension refers to how even-tempered, calm, easy-going, anxious, depressed, envious or volatile a person is. The psychotic-normal dimension is rare because most people will score low on the psychotic scale: it refers to how aggressive you are towards others, the level of concern and empathy you show others, and how impersonal and cold you are etc. Eysenck argued that differences in people’s personalities could be reduced to these dimensions, which related to the underlying functioning of the individual’s nervous system – central nervous system and autonomic nervous system. Eysenck maintained that the 3 characteristics of psychoticism (P), extraversion (E) and neuroticism (N), which he thought were influenced by our biology, could explain criminality: he described this as the PEN personality. some studies have supported aspects of Eysenck’s theory and shown a clear link between high levels of delinquency and high PEN scores. However, studies of convicted offenders, compared with non-offenders, does not produce consistent correlations. Problems with self-report data.there have been issues with the methodology used, e.g. that when criminal personalities have been assessed they have not been matched with an appropriate control group of non-criminals. Eysenck (1977) found criminals score more highly on scales of extraversion, neuroticism and psychoticism, as measured by the EPQ, than non-criminal controls. However, Passingham (1977) suggests that there are methodological flaws with the research, namely that the control group were not matched with the criminal group on important variables, such as socio-economic status, cultural background and IQ. Eysenck believed that a criminal personality displayed the following 3 personality dimensions: high P scores are aggressive, antisocial, cold and egocentric; high E scores are sociable, active, lively and sensation seeking; high N scores are anxious, depressed and react very strongly, i.e., negatively, to aversive stimuli and have a high degree of instability.

Question 51

Raine et al (1997) - personality

Answer 51

showed that in a study of 41 convicted murderers, there was lower levels of activity in the prefrontal cortex of the murderers compared to the control group, and differences in the functioning of the limbic system in the brain scans of the impulsive murderers, i.e., more aggressive and reduced ability to control aggressive impulses. Another study by Raine et al (2000) found that participants with anti-social personality disorder have a smaller PFC than normal participants, when looking at the volume of the brain. This is consistent with the findings of the 1997 study which found that murderers have lower levels of activity than the control in the PFC.

Question 52

Zuckerman (1969), Smith et al (1989) - personality

Answer 52

argue that sensation seekers have a more excitable nervous system, i.e., higher activity in the sympathetic nervous system, not less, therefore, sensation-seekers may not actually be seeking out activities to stimulate the nervous system, but are doing so because they have a tendency to be more easily aroused. Thus, unlike Eysenck’s proposal, they would argue that boredom comes from increased rather than decreased arousal, being easily arousable makes you bored more easily so need to seek out new sensations and stimulation.

Question 53

Rutherford et al (1999) - personality

Answer 53

Only about 20% of people with antisocial PD scored high on the Hare checklist.

Question 54

Stone (2007) - personality

Answer 54

investigated relationships between certain personality disorders and violent crime. Using personal interviews and looking at media reports of offenders convicted of such offences, Stone was able to assess the offenders to see if they had a PD. Results: antisocial and paranoid PDs are most common PDs among violent offenders, psychopathy was also common among violent offenders, narcissistic traits were high though not severe enough to reach a clinical diagnosis of narcissistic PD, instrumental (as opposed to impulsive) killers who murdered their partners were strongly associated with narcissistic PD, men committing serial sexual homicide usually show psychopathy, mass murderers usually show strong paranoid traits, and many had more than one PD.

Question 55

Spitzer (1975) - classic study

Answer 55

the clinicians were not being asked to distinguish between normal and abnormal as such, i.e., they were not looking at the accuracy of the diagnosis, they were not being asked the legitimacy of the symptoms – it could be argued that the pseudo patients did present the symptoms of schizophrenia, they said they heard a voice. Each pseudo patient insisted on admission, this is in itself usually an important symptom of emotional disturbance. It is hard for doctors to make the correct diagnosis if the person is faking symptoms, e.g., if someone swallowed a pint of blood then vomited blood, the diagnosis might be a peptic ulcer, which it could easily be, i.e., most of the time doctors are not looking for, or being presented with, deception.

Question 56

Lauren Slater - classic study

Answer 56

a recent attempt as replication by Lauren Slater for her book, Opening Skinner’s box, also supported Rosenhan’s findings. She went to 9 hospitals reporting hearing a voice saying ‘thud’ and was diagnosed with depression with psychosis and prescribed antipsychotic and antidepressant medication. However, Spitzer et al (2005) challenged these findings. In this research 431 psychiatrists were sent details of Slater’s symptoms, i.e., her account of her methodology, and were asked to make a diagnosis: 73 responded and 86% categorically ruled out the diagnosis Slater claimed she was given. One third would prescribe antipsychotic medication but none would prescribe antidepressants.

Question 57

Fleischman (1973)

Answer 57

Also they were all given the label ‘in remission’, i.e., diagnosed as no longer being psychotic, which was 100% accurate.

Question 58

Davis (2009) - 4Ds

Answer 58

individuals suffering from MHDs have a 25% higher chance of dying from unnatural causes.

Question 59

Goffman (1968) - diagnostic systems

Answer 59

maintains that labelling someone mentally ill stigmatises them, and that the stigma of mental illness remains long after the individual has recovered from the mental disorder.

Question 60

Scheff (1966) - diagnostic tools

Answer 60

argues that a process similar to self-fulfilling prophecy occurs when someone is labelled as mentally ill. The individual may behave according to the diagnosis, especially since there are often rewards associated with adopting the role of mental illness and punishments for trying to escape from it, e.g., abdication of responsibility vs stigma attached to not conforming to authority or expert figures.

Question 61

Danish researcher Alice Theilgaard (1984) - XYY syndrome

Answer 61

notes although there is a marginally higher rate of XYY men in the prison population than the general population, it is only very small and therefore cannot be the only reason for criminal behaviour amongst men, otherwise the proportion would be much higher. Instead, she argues than men with XYY syndrome tend to have lower levels of intelligence, therefore, the higher than normal level of XYY syndrome men the in prison population might reflect this trait rather than aggression. Theilgaard points out that no single characteristic other than height has been exclusively associated with XYY syndrome, i.e., other features thought to be a feature of XYY syndrome are also features of other conditions.She suggests that being taller than average may be linked to higher than normal levels of aggression. Theilgaard reports that some studies of XYY males show them to have normal levels of testosterone, other show slightly higher than normal levels. Testosterone has been linked to aggression. Finally, she notes that XYY males have lower intellectual ability than normal, poorer concentration spans, report more difficulties with relationships and unhappier childhoods, and are more rigid in their thinking, impulsive, more pessimistic and in TAT appraisals displayed more aggressive and less anti-aggressive content and were more evasive and less harmonious – i.e., all traits that may lead to aggressive behaviours, rather than XYY syndrome being directly linked to aggression. Theilgaard reports findings of higher than normal levels of testosterone in XYY males but interestingly found high levels of testosterone in XY males who had been convicted of crimes.

Question 62

Stockholm et al (2012) - XYY syndrome

Answer 62

suggests that even when there is a link between XYY syndrome and criminality, it tends to come from unfavourable living conditions, not from genes.

Question 63

Re and Birkhoff (2015) - XYY syndrome

Answer 63

conclude that there is no statistical evidence to suggest that XYY syndrome predisposes males, just because of genotype, to aggressive and deviant behaviour.

Question 64

Slutske et al (1997) - genes

Answer 64

has shown a higher incidence of conduct disorder in twins when compared to singletons

Question 65

Hutchings and Mednick (1997) - genes

Answer 65

found that 85.7% of male adoptees with a criminal or minor offences record had a biological father with a criminal record, compared with adoptees without a criminal record who had a criminal father 31.1% of the time.

Question 66

Brunner (1993) - MAOA

Answer 66

evidence for a genetic component of aggression came from a group of men from the same large family in the Netherlands who presented persistent and pronounced aggressive behaviour, such as rape, assault, attempted murder, burglary, arson and exhibitionism. A few also presented mild mental retardation. Brunner (1993) studied the men and noted that some of them carried a faulty version of a gene responsible for the production of an enzyme called monoamine oxidase A – MAOA. The mutation was in their X chromosome – the genetic material we inherit from out mothers. other research has also shown that men with the lower activity version were found to be more likely to engage in impulsive and aggressive behaviour.

Question 67

Capsi et al (2002) - MAOA

Answer 67

studied a cohort of people whose lives had been monitored from the age of 3 to 26 through surveys, family reports, tests and interviews. The research found that although MAOA along had no large effect, it definitely modulated the impact of early-life maltreatment on later anti-social behaviour. Over 80% of those with the low-activity of the MAOA gene ended up developing anti-social behaviour, but only if they had been exposed to maltreatment and abuse during their lives.