Biological Explanations for Offending Behaviour (Genetic and Neural) Flashcards
(10 cards)
Outline the genetic explanation for offending behaviour.
The genetic explanation proposes that some individuals inherit genes that predispose them to criminal behaviour. One example is a low-activity variant of the MAOA gene, which is responsible for producing enzymes that break down neurotransmitters such as dopamine and serotonin. A low-activity MAOA gene results in fewer enzymes, leading to higher levels of serotonin and dopamine in the brain. High serotonin levels can cause desensitisation of serotonin receptors, reducing its calming effects and making individuals more impulsive or aggressive. Meanwhile, high dopamine levels can drive reward-seeking behaviour, which may lead to crimes like theft or burglary.
Give a strength of the genetic explanation for offending behaviour.
A strength is that it has supporting evidence from twin studies. Research shows higher concordance rates for criminal behaviour in MZ twins (who share 100% of their genes) compared to DZ twins (who share 50%). This suggests a genetic influence on offending, as MZ twins are more likely to both display criminal behaviour, adding credibility to the genetic explanation.
Give another strength of the genetic explanation: adoption studies.
Further support comes from adoption studies. Research has found that children whose biological parents had criminal records were more likely to engage in criminal behaviour, even when raised by non-criminal adoptive families. This implies that genetics, rather than environment, can influence criminal behaviour, providing further credibility for the genetic explanation.
Give a limitation of the genetic explanation: confounding variables in twin studies.
A limitation is that MZ twins often share more similar environments than DZ twins. Because they are the same sex and look alike, they may be treated more similarly and have the same friends, exposing them to the same pro-criminal influences. This suggests that the higher concordance rates in MZ twins may be due to shared environments, not genetics, which questions the credibility of genetic explanations.
Give a limitation of the genetic explanation: biological determinism.
Another limitation is that the genetic explanation is biologically deterministic, implying that individuals are not responsible for their actions because of their genes. This poses ethical issues in the justice system, which assumes people have free will and should be held accountable for their actions. If genes entirely control behaviour, this would challenge how society views criminal responsibility and punishment.
Outline the neural explanation for offending behaviour.
The neural explanation suggests that abnormalities in brain structure or function can lead to offending behaviour. Brain scans have shown reduced activity in the prefrontal cortex, an area involved in decision-making and impulse control, in many offenders. Low activity here could lead to poor judgement and impulsive crimes. In addition, offenders often show reduced activity in the amygdala, which processes emotions like fear. This may make them less able to empathise with victims or fear consequences, increasing their likelihood of committing crimes.
Give a strength of the neural explanation: brain scanning studies.
Brain scanning research supports the neural explanation. Men with lower amygdala volumes are more likely to be violent, and people with antisocial personality disorder have shown reduced activity and tissue in the prefrontal cortex. This strengthens the idea that brain abnormalities may lead to criminal behaviour, adding credibility to the neural explanation.
Give another strength of the neural explanation: TMS studies.
Further support comes from TMS (transcranial magnetic stimulation) studies, which increase activity in certain brain regions. Research found that stimulating the prefrontal cortex led to a reduction in criminal intentions and increased perception of aggressive acts as morally wrong. This suggests that low prefrontal activity can play a role in offending, supporting the neural theory.
Give a limitation of the neural explanation: individual differences.
A limitation is that it doesn’t explain all types of criminals. For example, successful psychopaths often have overactive prefrontal cortices and may commit calculated, organised crimes. Also, not all offenders have reduced amygdala activity — some may have overactive amygdalas, especially those committing emotionally driven crimes. This suggests the neural explanation is too simplistic, reducing its overall credibility.
Give a limitation of the neural explanation: biological determinism.
Like the genetic explanation, the neural explanation is biologically deterministic. It assumes people commit crimes because of brain abnormalities outside their control, which raises ethical issues. In the justice system, we expect individuals to be responsible for their actions. If behaviour is driven by uncontrollable brain activity, this challenges the fairness of legal punishment.
