Forensics: Biological Explanations Of Offending Flashcards
What is a neural explanation?
Any explanation of behaviour (and its disorders) in terms of (dys)functions of the brain and nervous system, includes brain structures such as the hypothalamus and neurotransmitters such as serotonin and dopamine. Evidence suggests neural differences in the brains of criminals and non-criminals
What is a genetic explanation
An explanation that says offenders inherit a gene, or combinations of a gene that predispose them to commit crime, twin studies, adoption studies, diathesis-stress model, candidate gene
Describe and explain the twin study with twins in prison
Researchers investigated 13MZ and 17DZ twins where one of the twins in each pair had served time in prison, they found that 10/13 MZ twins had a co-twin who was also in prison (77% concordance rate) whereas only 2/17 DZ twins had a co-twin who was also in prison (12% concordance rate). It was concluded that genetic factors play an important role in offending behaviour
Describe and explain the adoption study with adopted children whose mothers had criminal records?
Researchers compared a group of adopted children whose mother had a criminal record to a control of adopted children whose mothers did not have a criminal record, 50% of adopted children whose mothers had a criminal record had a criminal record by the time they were 18, compared to 5% of the control group. This suggests regardless of the changed environment, children seemed biologically predisposed to criminality
Describe and explain the candidate gene study
Researchers conducted a genetic analysis of 900 Finnish offenders, MAOA (controls dopamine and serotonin, linked with aggression), and CDH13 (protein coding, linked to substance abuse and attention deficit disorder) individuals with both genes were 13 times more likely to have a history of violent behaviour
What is the diathesis-stress model explanation?
There is a link between genetic predisposition and biological and psychological trigger, for example being raised in a dysfunctional environment or having a criminal role model. Diathesis = vulnerability, stress = psychological trigger (e.g. child abuse)
What is the prefrontal cortex link with criminality?
Individuals who experience APD (reduced emotional responses and lack of empathy for others) show reduced activity in the PFC, the part of the brain that regulates emotional behaviour
Describe and explain the study of grey matter in the PFC with people with APD vs non
Researchers found an 11% reduction in the volume of grey matter in the PFC of people with APD compared to control groups, participants wore headphones and were instructed to press a button when they heard a beep, this activates the PFC, 41 NGRI vs 41 controls, showed differences in neural activity, for example deficits in the PFC, which can lead to someone being more impulsive and emotional
Supporting research for genetic and neural explanations
Twin study, adoption study, candidate gene study, PFC grey matter study
Research against genetic and neural explanations
It’s not easy to separate genetic and environmental influences in adoption study due to late adoption, regular contact with biological parent, difficult to assess environmental impact, criminality could be due to inherited emotional instability or mental illness. It explains criminality too simplistically and biologically reductionist, could be other causes in the family such as emotional instability, social deprivation, poverty. No study shows 100% concordance rate between MZ twins. Criminal gene presents ethical problem for legal system as its biological determinism and negates free will, implications with sentencing
What is the atavistic form?
A biological approach to offending proposed by Lombroso that attributes criminal activity to the fact that offenders are genetic throwbacks or a primitive subspecies ill-suited to conforming to the rules of modern society. Such individuals are distinguishable by particular facial and cranial characteristics
What did Lombroso believe about the facial and cranial characteristics of offenders
He believe offenders were lacking evolutionary development and their savage and untamed nature meant they found it impossible to adjust to the demands of society and would inevitably turn to crime. He theorised criminals could be identified by physiological characteristics mainly on the face and head, such as narrow, sloping brows, a strong prominent jaw, high cheekbones, facial assymetric dark skin, also extra toes, nipples, fingers etc. He also identified other factors such as insensitivity to pain, tattoos, unemployment, use of slang etc
What was Lombroso’s research?
He examined cranial and facial features of living and dead criminals, 383 skulls, and 3839 living criminals, concluded that 40% of criminal acts could be accounted for by people with atavistic characteristics. Their characteristics indicated specific types of criminals, murderers (bloodshot eyes, strong jaw, long ears, curly hair), sexual deviants (glinting eyes, swollen, fleshy lips and projecting ears), fraudsters (thin and reedy lips)
Support for Lombroso
Shifted emphasis in crime research away from moralistic discourse towards a scientific credible realm. Atavistic characteristics was the foundation of criminal profiling
Against Lombroso
Support for eugenics movement, ‘scientific racism’, many of the features that Lombroso identifies are more likely to be found among people of African descent. Limited support to the argument of ‘sub species’ in terms of lower intelligence. 3000 criminals + non criminals with physical or mental abnormalities, no evidence that offenders were a distinctive group with facial/cranial characteristics. Issues with research: Lombroso didn’t use a control group, could be confounding variables. Causation issue, could be poverty related not lack of evolution
