A2 FORENSIC PSYCHOLOGY - BIOLOGICAL EXPLANATIONS; ATAVISTIC FORM AND GENETIC AND NEURAL EXPLANATIONS

Question 1

Describe atavistic form as a bio expl of offending

Answer 1

Lombroso said that criminals are genetic throwbacks and are bio different to non-criminals; they lack evolutionary dev and can’t adjust to demands of civilised society

He said that someone’s physical characteristics can indicate whether someone is a criminal and what type of crime thy’ll commit.

Question 2

Describe some physical characteristics from atavistic form

Answer 2

Cranial: narrow, sloping brow; strong, prominent jaw; high cheekbones and facial asymmetry.

Other physical characteristics: dark skin; extra toes, fingers and nipples

 - Murderers would have bloodshot eyes, curly hair and long ears.
 - Sexual deviants e.g. rapists, paedophiles etc, would have glinting, glazed eyes and swollen, fleshy lips
 - Fraudsters would have thin, reedy lips 

Other general characteristics that criminals would possess include insensitivity to pain; unemployed; tattoos and criminal slang.

Question 3

Evaluate atavistic form

Answer 3

(+) Lombroso studied the facial and cranial characteristics of 3839 living criminals and 383 dead ones and found that about 40% of them had atavistic characteristics
(-) This evidence is weak as not only did 60% of those he studied not show his characteristics, but he also did the research himself so researcher bias, and he didn’t use a control group to see how many non offenders normally have atavistic characteristics, so v low validity
(+) Despite criticisms, he did make first attempt to explain criminal beh scientifically and biologically; “father of modern criminology”
(-) Racist undertones; many of L’s characteristics are likely to be found in ppl of African descent; discriminatory and prejudiced approach

Question 4

Describe and evaluate a twin study for genetic explanations of offending

Answer 4

• Lange (1930) studied 13 MZ and 17 DZ sets of twins where one had already been in prison. Found conc rates of 10/13 and just 2/17
  (+) As conc (MZ) > conc (DZ), suggests some genetic influence in offending
  (-) Conc (MZ) =/= 100% so not wholly genetic
  (-) MZ twins share a more similar env so may be env.al factors not genetic ones
  (-) Poorly controlled and zygosity was determined by appearance in these early exp.s and not genetics so lacks validity.

Question 5

Describe and evaluate monoamine oxidase A - low variant as an expl of offending

Answer 5

MAOA-L (monoamine oxidase A - low variant) is responsible for codng NTs like serotonin and dopamine; low levels of MAOA can lead to aggression, so links to violent crime (known sometimes as the “warrior gene”/ “psycho gene”
(+) Brunner found that MAOA-L was common in a Dutch family of 28 violent offenders
(+) Can explain why there are fewer female violent offenders than male; MAOA linked to X chromosome; females have a “spare one” to balance out one that leads to MAOA-L
(-) 40% of the general pop have MAOA-L variant, but they’re not all violent, and not all violent ppl have it; other factors involved
(+) Tiihonen (2015) found that out of a Finnish sample of 900 offenders, they were 13 times more likely to commit a violent crime if they had a combo of MAOA-L and CDH13 than those without.
(-) Research is in its infancy and has not yet been replicated.

Question 6

Describe and evaluate Cadherin 13 (CDH13) as an expl of offending

Answer 6

CDH13 (Cadherin 13) is a gene responsible for ADD (previously ADHD); attention deficit disorder.
(+) Tiihonen (2015) found that out of a Finnish sample of 900 offenders, they were 13 times more likely to commit a violent crime if they had a combo of MAOA-L and CDH13 than those without.
(-) Research is in its infancy and has not yet been replicated.

Question 7

Describe the diathesis stress model of offending.

Answer 7

Genetics aren’t the only factor involved in offending; there’s an interaction bet genes and the env. There needs to be an event to trigger the genetic predisposition

Caspi et al (2002) did a longitudinal study of 1000 kids form when they were babies to 26 yrs old, and found that 12% (who were responsible for 44% of violent crime) had a combination of genetic vulnerability and mistreatment as a child; diathesis stress.

Question 8

Describe the neural explanation of offending (not finished)

Answer 8

Raine et al (1997) found that murderers had abnormalities in the amygdala (underfunctioning on LHS, overactivity on RHS), which is part of the limbic system, which is linked to emotion and motivation.

Raine (2004) also found low functioning in pre-frontal cortex in murderers and psychopaths, which is responsible for controlling emotionally impulsive behaviour

Question 9

Evaluate genetic and neural explanations of offending

Answer 9

(- neural) Correlation not causation, so may not be able to predict future criminal beh.
(- gen and neural) Can only explain violent crime; limited explanatory power
(- gen and neural) Bio expls are too reductionist; oversimplifies the complex issue of criminality
(- gen and neural) Bio expls are too deterministic; removes accountability and poses problems for the justice system; if beh is determined by genes or neural abnormalities, can we really punish people for it?