biological theories: physiological Flashcards
what are the 3 physiological theories
lombroso
Sheldon
raine
what are the three genetic biological theories of crime?
jacobs XYY
adoption studies
twin studies
claims of lombrosos theory
the criminal is a separate species a species that is between modern and primitive humans.
argued that the physical shape of the head and face determined the “born criminal”.
claimed that you can tell what kind of crime someone will commit by the way they look.
components of lombrosos theory
examined facial features and skulls of 383 dead criminals, 3839 living criminals and concluded 40% of the criminal acts could be accounted for due go those with atavistic characteristics.
what is Atavistic characteristics
large jaw and high cheekbones, flattened or upturned nose, handle shaped ears, large chin hawk like nose or fleshy lips, hard shifty eyes, scanty beard or baldness, insensitive to pain, long arms.
Features of a thief
expressive face, manual dexterity, and small wanderings eyes
features of murderer
cold glassy stare bloodshot eyes and big hawk like nose
features of a sex offender
thick lips big ears
Features of women offenders
shorter and more wrinkled darker hair and smaller skull than normal women
credibility of lombrosos theory
the first person to give criminology a scientific credibility (1835-1909) were religious or moralistic before this.
The theory had a scientific test and there was a large sample size.
However, the theory had no control group of non-criminals there was no comparison.
applications of lombrosos theory
he labelled prisons “criminal universities” he said people will leave the prison much more violent/ criminal than when they entered, given today recidivism rates this was very perceptive.
refuting evidence of lombrosos theory
no control group (no study of non-criminals)
possible disfigurement
not everyone with atavistic features is criminal and not all criminals have atavistic features
scientific racism- some features are those linked to race/ ethnic groups.
supporting evidence of lombrosos theory
a Chinese university study showed that ai can identify criminals using facial recognition software. 83% of criminals were identified and only 6% of the innocent people were wrongly identified.
claims of Sheldons theory
Sheldon advanced Lombroso’s theory an also claimed that criminal behaviour is linked to a person’s physical form.
By looking at 4000 barely clothes men Sheldon claimed that people could be classified into 3 different body types or somatotypes
what is ectomorphic
thin and fragile are introverted and restrained
what is Endomorphic
fat and soft tend to be sociable and relaxed
what is mesomorphic
muscular and hard tend to be aggressive and adventurous. mesomorphic people are more likely to be criminal
components of Sheldons theory
Sheldon used a correlation study where he asked people to rate 200 photos on a scale 1-7 according to how close to mesomorphic type each was
Half the photos were of college students and half were of juvenile delinquents the delinquents had a higher average rating as mesomorphic
From his studies Sheldon found that many convicts were mesomorphic and they were least likely to be Ectomorphic. He argued that Ectomorphs were more likely to commit suicide, mesomorphs were more likely to engage in crime, endomorphs were more likely to be mentally ill
credibility of Sheldons theory
Sheldon used a large sample of 200 in his study and had a control group of students to link his theory to.
It is an androcentric study (focuses on men)
there are scientific links between testosterone and muscle mass
applications of Sheldons theory
Applied to Kray twins, ted Bundy, however, didn’t fit for Dennis Neilson and al Capone
refuting evidence of Sheldons theory
One person could be all 3 types as body’s change.
This theory suggests that we are born. To be bad and cannot escape that fate.
claims of raines study
damage to the prefrontal cortex of the brain may cause individuals to have an altered behaviour pattern.
Damage to the prefrontal cortex can impair impulse control this means that if this part of the brain is damaged we may become more aggressive or violent because we can no longer control our impulse behaviours.
components of Raines study
used a pet scanner to study the living brain of 41 impulsive killers who had pleaded reasons of insanity as their defence, all 41 had damage to their prefrontal cortex
Used different stimuli and recorded how the brain reacted comparing normal brains to that of the impulsive killers
Murderers pleading insanity had significant differences in brain function in a number of brain areas compared to non-murderers
what is a PET scan
positron emission tomography
a functional scan, it can show how the brain is working during different tasks by measuring blood flow, it can also show the size of the brain areas so that they can be measured and compared between people
credibility of Raines theory
scientific and objective pet scanners are technical specialist equipment.
Generalisation are possible with a large enough size.
Doesn’t establish when the murderers suffered prefrontal cortex damage this may have happened after the crime within the sample.
Deterministic- implies that PFC damage inevitably leads to violent offending
applications to Raines study
Donna Page, raped a woman in Denver ,1999
Raine said “I was an expert witness in this case. Compared to normal controls brain scans revealed he had a distinct lack of activation in the central prefrontal cortex the region that helps regulate our emotions and control our impulses”
He was also brought up in a horrible environment neglected and physically & sexually abused, thrown out a car window when he was just 9 months old and suffered multiple head injuries as a child.
refuting evidence of Raines theory
It can only be generalised to murders pleading guilty due to reasons of insanity
Raine stated that the pet scans used where not clear and that there was a limit to how accurately they could be measured causing the study to lack internal validity
supporting evidence of Raines theory
Bandura claimed that if people learn aggressive behaviours their brain might change because of it, means that physical aggression may be wired into the brain after it Is learnt through childhood.
