2.1- Describe Biological Theories Of Criminality Flashcards
Physiological theories-
Lombroso’s Theory- Born criminals
He argued criminals were physically different-
-enormous jaws, prominent eyebrow arches, high cheekbones, long arms, handle shaped ears, large eye sockets.
Atavism- pre social, unable to control impulses and reduced sensitivity, lombroso argued that criminals possessed these characteristics and compared them to savages.
Physiological theories-
Shelton’s somatotypes theory
Endomorphs- rounded, soft, lacking tone or muscle. With a sociable and relaxed personality.
Ectomorphs- thin and fragile. With a self conscious and emotionally restrained personality.
Mesomorphs- muscular and hard bodied with very little fat and strong limbs. They are adventurous assertive and dominating.
Sheldon argued that mesomorphs are the somatotypes attracted to crime from the risk it possesses and their physical strength
Genetic theories-
Twin studies- Christiansen’s study
He studied 3,586 twin pairs in Denmark and found a 52% concordance rate between identical twins (meaning if one twin had a conviction there was a 52% chance the other would also have a conviction). And among non identical it was 22%.
Genetic studies-
Adoption studies
Mednick examines data on over 14,000 adopted sons from Denmark from 1924-1947 and found they were more likely to have a criminal record if their birth parents also had one.
Genetic theories-
Jacobs XYY study
If there is an extra male chromosome in the body (XYY) this creates abnormalities in the genetic make up of the male causing the ‘super male syndrome’. They tend to be very tall and well built.
They studied imprisoned criminals and found there was a high proportion with this genetic makeup
Brain injuries and disorders-
Brain injuries
Rare cases of Brain injuries cause a change to the personality which can sometimes become criminal.
Phineas Gage suffered a Brain injury resulting in the loss of his frontal lobe (moral reasoning) causing a deviant shift in his personality
Brain injuries and diseases-
Diseases
Some brain diseases have been linked to anti social behaviour such as the 1920 s epidemics of encephalitis lethargica among children showing destructiveness, impulsiveness and abnormal sexual behaviour.
Abnormal brainwave activity is measured by an electroencephalograph and some abnormal readings can be seen in prison.
Biochemical explanations-
Sex hormones
Males- over/underproduction of hormones may cause emotional disturbances as males are typically more aggressive. Similarly Ellis and Coontz saw that testosterone levels peaked at teenaged years which cooperates with the highest crime levels in males.
Females- pre-menstrual tension, postnatal depression and lactation effect mood and self control and can be used in the court of law
Biochemical explanations-
Blood sugar levels
Hypoglycaemia (low blood sugar) can trigger aggressive reactions and combined with alcohol which lowers blood sugar anyway can cause violent outbursts.
Schoen claims lowing daily sucrose intake of young offenders could reduce anti-social behaviour.
Biochemical explanations-
Substance abuse
Saunders calculated that alcohol was present in 80% of family violence and cocaine is also linked to violence whereas cannabis, heroin and MDMA can reduce aggression
Biochemical explanations-
Other substances
Diet can be linked to anti social behaviour as they effect various biochemical processes in the body.
Lead and synthetic food colouring tartrazine have been linked to hyperactivity.
Vitamins B deficiency have all been linked to erratic and aggressive behaviour.
Biological theories
•Physiological- *lombroso’s theory: born criminals *sheldon’s somatotypes theory •Genetic theories- *twin studies- Christiansen’s study * mednick’s adoption studies * Jacob’s XYY study •Brain injuries and disorders •Biochemical explanations- *sex hormones *blood sugar levels *substance abuse * others
