Biological Explanations: Genetic and Neural Explanations Flashcards
Lange date
1930
Lange studied
13 MZ and 17 DZ twins where one of the twins had been sent to prison
Lange - ten of the MZ twins had a co-twin who was also in prison but
this was only true for two of the DZ twins
Crowe date
1972
Crowe found that adopted children who had a biological parent with a criminal record had a
50% greater risk of a criminal record by the age of 18
Crowe also found that adopted children whose mother didn’t have a criminal record only had a
5% risk
Tiihonen et al
2014
Tiihonen et al conducted a genetic analysis of
900 offenders
Tiihonen et al found
two genes that may be associated with violent crime
what are the two genes that Tiihonen et al identified?
The MAOA gene.
The CDH13 gene.
having a weakness in both the MAOA gene and the CDH13 gene led to individuals being
13 times more likely to have a history of violence
if genes have an influence on offending,
this influence is likely to be at least partly moderated by environmental factors
a tendency to criminal behavior may come about through a combination of
Genetic predisposition.
A biological or psychological stressor or trigger
antisocial personality disorder
there may be neural differences in the brains of criminals and non-criminals
antisocial personality disorder is associated with
Lack of empathy
many criminals suffer with
antisocial personality disorder
Raine et al date
2000
Raine et al found an
11% reduction in the volume of grey matter in the in the prefrontal cortex of people with antisocial personality disorder compared to a control
the prefrontal cortex controls
emotional behavior
Keysers date
2011
Keysers found that only when criminals were asked to emphesise
they showed an empathy reaction
because antisocial personality disorder do show emotions
this shows that sufferers are capable of emotion but they have a switch which turns them on and off
in a normal functioning brain, the switch is always
on
Lange research was
poorly controlled