Criminal Psychology
Explanations of crime and anti-social behaviour, with consideration
given to gender differences - Biological explanations including brain
injury, amygdala and aggression, XYY syndrome and personality.
Brain injury
If the frontal lobe is damaged then the person has less control over
their impulses, so this may make them more aggressive.
Damage to the frontal lobe also negatively affects our ability to consider
alternative behaviours and think about possible consequences of
aggression
Williams 2010 – 60% of people who committed a crime in the study reported
having a head injury and lots of injuries means people are more likely to
reoffend, more violently
Damage to the amygdala can lead to less control over aggressive
impulses, so making someone more aggressive.
Role of drugs - Kreutzer (1995) - sample of 327 patients with traumatic brain
injury and arrest histories and behaviour, compared to those who had not
suffered brain injuries, analysis revealed that without the presence of substance
misuse, traumatic brain injury was not a risk factor for criminal behaviour
Traumatic Brain Injury: TBI can occur through direct trauma on the
brain. Young males are most at risk of TBI, leading to an inability to
prevent impulsivity. TBI can also occur through long term alcohol
consumption and drug use…they impair absorption of B1 needed for
the brain to function. Drunkenness itself can impair decision making
and make trauma to the head more likely
Do other factors increase likelihood? Diaz (1995) being a young male and
substance misuses are all linked to likelihood of brain injury. This makes it
difficult to isolate brain injury from these underlying factors as the case.
The brain is not thought to be fully developed until 25. Having a brain
injury can disrupt development and may destabilise mood and decision
making.
+Useful application: Our understanding of brain injury and crime means
recommendations that neural injuries be looked at in the same way as mental
health is in court and taken into account during sentencing. The English FA has
introduced a no heading rule for under 12s as a result of various research into
the long-term effects of brain damage.
,Amygdala and aggression
The amygdala processes information from our senses and determines how we
respond to that information
Yang 2009 found that in people with psychopathy, their amygdala was 17%
smaller in volume and their right amygdala was 18% smaller in volume than
controls. Therefore, those with lower metabolic processing in their amygdala is
linked with crime.
The amygdala can trigger the flight or fight response when we run away from the
situation or stay and fight
+Animal research; When the amygdala was electrically stimulated, cat attacked
and killed a rat. Later research showed that when the amygdala is ablated
(removed or destroyed) cats become much more placid but if the area was
electrically stimulated then aggression would be displayed - HOWEVER…
Animal research is a) controlled so we can easily see the impact disrupting the
amygdala has but b) lacks generalisability - the decision making capabilities are
not the same
When it is activated the amygdala overrides the rational part of our brain so we
are less likely to think in a rational manner
+Use of scanning techniques is a strength as it is objective and can easily be
compared.
Damage to the amygdala can lead to an individual being unable to prevent
themselves acting spontaneously in an aggressive way
+Useful application… but social control!!
If we identify small amygdalae in a young person, certain interventions could be
put in place, however doesn't mean they will become a criminal and therefore
can be seen as a form of social control
, XYY syndrome
XYY is caused by males having an extra Y chromosome thought to be due to an
error when the cells divide
-Reductionist: The presence of an extra Y is only a risk factor, which cannot be
the only cause of deviant behaviours...... Women also engage in criminal
behaviour including violent crime (albeit to a lesser extent), therefore cannot be
the only explanation for criminal behaviour.
About 50% of boys who have XYY syndrome will have some delay when
developing their speech
Boys who have XYY syndrome have normal intelligence, but their intelligence
may be 10 to 15 IQ points below their siblings
+Research evidence (Theilgaard 1984): Took blood samples from 30,000 men
in the 1940's and tracked them for many years afterwards. 12 had the XYY
chromosome abnormality. Each of the men were given intelligence and
personality tests and their criminal histories / backgrounds were checked. The
study found that XYY males had slightly lower intelligence than other males
and tended to be more aggressive towards other people and lack empathy.
However...The main link between crime and XYY comes from observation of
these individuals in criminal populations, where they are over represented. 75%
of cases are thought to never be diagnosed – suggesting many are not deviant in
their behaviour
1 in 1000 males are born with an extra Y chromosome so they have 47
chromosomes (1).
This leads to the males being slightly taller than their siblings, and having a
slightly lower intelligence than their siblings (1).
XYY can also lead to the males being more impulsive, and having behavioural
problems (1).
Some XYY males are also more physically active, all of these can lead to anti-
social behaviour (1).
-Research evidence (Birkhoff 2015): Considered 50 years of evidence (which
has become more technologically advanced) and concluded that there was no
conclusive link between XYY and an individual becoming deviant or anti-social.
This reduces the credibility of the explanation but is important...
if we can prove there is no link then these people cannot blame their XYY status,
and a self-fulfilling prophecy may be stopped if society are aware
Explanations of crime and anti-social behaviour, with consideration
given to gender differences - Biological explanations including brain
injury, amygdala and aggression, XYY syndrome and personality.
Brain injury
If the frontal lobe is damaged then the person has less control over
their impulses, so this may make them more aggressive.
Damage to the frontal lobe also negatively affects our ability to consider
alternative behaviours and think about possible consequences of
aggression
Williams 2010 – 60% of people who committed a crime in the study reported
having a head injury and lots of injuries means people are more likely to
reoffend, more violently
Damage to the amygdala can lead to less control over aggressive
impulses, so making someone more aggressive.
Role of drugs - Kreutzer (1995) - sample of 327 patients with traumatic brain
injury and arrest histories and behaviour, compared to those who had not
suffered brain injuries, analysis revealed that without the presence of substance
misuse, traumatic brain injury was not a risk factor for criminal behaviour
Traumatic Brain Injury: TBI can occur through direct trauma on the
brain. Young males are most at risk of TBI, leading to an inability to
prevent impulsivity. TBI can also occur through long term alcohol
consumption and drug use…they impair absorption of B1 needed for
the brain to function. Drunkenness itself can impair decision making
and make trauma to the head more likely
Do other factors increase likelihood? Diaz (1995) being a young male and
substance misuses are all linked to likelihood of brain injury. This makes it
difficult to isolate brain injury from these underlying factors as the case.
The brain is not thought to be fully developed until 25. Having a brain
injury can disrupt development and may destabilise mood and decision
making.
+Useful application: Our understanding of brain injury and crime means
recommendations that neural injuries be looked at in the same way as mental
health is in court and taken into account during sentencing. The English FA has
introduced a no heading rule for under 12s as a result of various research into
the long-term effects of brain damage.
,Amygdala and aggression
The amygdala processes information from our senses and determines how we
respond to that information
Yang 2009 found that in people with psychopathy, their amygdala was 17%
smaller in volume and their right amygdala was 18% smaller in volume than
controls. Therefore, those with lower metabolic processing in their amygdala is
linked with crime.
The amygdala can trigger the flight or fight response when we run away from the
situation or stay and fight
+Animal research; When the amygdala was electrically stimulated, cat attacked
and killed a rat. Later research showed that when the amygdala is ablated
(removed or destroyed) cats become much more placid but if the area was
electrically stimulated then aggression would be displayed - HOWEVER…
Animal research is a) controlled so we can easily see the impact disrupting the
amygdala has but b) lacks generalisability - the decision making capabilities are
not the same
When it is activated the amygdala overrides the rational part of our brain so we
are less likely to think in a rational manner
+Use of scanning techniques is a strength as it is objective and can easily be
compared.
Damage to the amygdala can lead to an individual being unable to prevent
themselves acting spontaneously in an aggressive way
+Useful application… but social control!!
If we identify small amygdalae in a young person, certain interventions could be
put in place, however doesn't mean they will become a criminal and therefore
can be seen as a form of social control
, XYY syndrome
XYY is caused by males having an extra Y chromosome thought to be due to an
error when the cells divide
-Reductionist: The presence of an extra Y is only a risk factor, which cannot be
the only cause of deviant behaviours...... Women also engage in criminal
behaviour including violent crime (albeit to a lesser extent), therefore cannot be
the only explanation for criminal behaviour.
About 50% of boys who have XYY syndrome will have some delay when
developing their speech
Boys who have XYY syndrome have normal intelligence, but their intelligence
may be 10 to 15 IQ points below their siblings
+Research evidence (Theilgaard 1984): Took blood samples from 30,000 men
in the 1940's and tracked them for many years afterwards. 12 had the XYY
chromosome abnormality. Each of the men were given intelligence and
personality tests and their criminal histories / backgrounds were checked. The
study found that XYY males had slightly lower intelligence than other males
and tended to be more aggressive towards other people and lack empathy.
However...The main link between crime and XYY comes from observation of
these individuals in criminal populations, where they are over represented. 75%
of cases are thought to never be diagnosed – suggesting many are not deviant in
their behaviour
1 in 1000 males are born with an extra Y chromosome so they have 47
chromosomes (1).
This leads to the males being slightly taller than their siblings, and having a
slightly lower intelligence than their siblings (1).
XYY can also lead to the males being more impulsive, and having behavioural
problems (1).
Some XYY males are also more physically active, all of these can lead to anti-
social behaviour (1).
-Research evidence (Birkhoff 2015): Considered 50 years of evidence (which
has become more technologically advanced) and concluded that there was no
conclusive link between XYY and an individual becoming deviant or anti-social.
This reduces the credibility of the explanation but is important...
if we can prove there is no link then these people cannot blame their XYY status,
and a self-fulfilling prophecy may be stopped if society are aware
