Neurotransmitters & Crime

Question 1

What is offending behaviour?

Answer 1

Broad term encompassing actions that violate societal norms, rules, laws or cause harm to others
- includes aggression, antisocial behaviour, criminal behaviour

Question 2

Who defined criminal behaviour and how?

Answer 2

• Davies et al., 2022
• actions that break the law, encompassing violent and non-violent crime

Question 3

Who defined violent crime and how?

Answer 3

• Archer, 2023
• crimes that use threat, violence, and force

Question 4

What are neurotransmitters?

Answer 4

Chemicals enabling communication between neurones

Question 5

What factors do neurotransmitters influence (and who suggested this)?

Answer 5

• Berman & Coccaro, 1998
• influence mood, thinking and behaviour

Question 6

What is the role of serotonin?

Answer 6

regulates behaviour and inhibits impulsive aggression

Question 7

Who studied CSF serotonin?

Answer 7

Glenn & Raine (2014)

Question 8

What did Glenn and Raine (2014) find?

Answer 8

low CSF serotonin levels are associated with impulsive aggression

Question 9

Who studied whole blood serotonin?

Answer 9

Moffitt et al. (1998)

Question 10

What did Moffitt et al. (1998) find in their study of whole blood serotonin?

Answer 10

• violent adults have higher blood serotonin levels than their non-violent peers
• results were significant after controlling for confounding variables

Question 11

What are some limitations of the study of blood serotonin?

Answer 11

• blood serotonin is largely produced in the gut, and contained in platelets, never entering the brain
• while some studies suggest low csf serotonin and high blood serotonin may occur due to shared serotonin transport, producing aggression (Cook et al., 1993), the relationship between blood serotonin and behaviour is unclear

Question 12

Who provided an alternative explanation for the correlation between blood serotonin (that never enters the brain) and behaviour (produced in the brain)?

Answer 12

• Cook et al., 1993
• suggested that the link between aggression, low csf serotonin, and high blood serotonin is because of shared serotonin transport

Question 13

Who investigated the role of serotonin-receptor binding in violent offenders?

Answer 13

da Cunha-bang et al. (2017)

Question 14

How did da Cunha-Bang et al. (2017) investigate serotonin-receptor binding, and what did the results find?

Answer 14

• Used PET scans and radiotracers to view serotonin-receptor binding in violent criminals versus a healthy control group
• found increased serotonin binding positively correlates with anger and psychopathy
• suggests low synaptic serotonin or high receptor density may cause this link

Question 15

What traits are often impaired in criminals, and who said this?

Answer 15

impulse control, emotional processing and decision-making
- Anderson & Kiehl, 2012

Question 16

What are the limitations of the da Cunha-Bang et al. (2017) study?

Answer 16

• small sample size, results are less generalisable due to less accurate representation of populations
• confounding variables such as IQ or history of substance abuse, possibly influencing findings

Question 17

What are the strengths of the Moffitt et al. (1998) study?

Answer 17

• large sample size with a diverse sample, strengthening the generalisability and ecological validity of results

Question 18

What relationship does dopamine have with the brain and offending behaviour?

Answer 18

relationship with the brain’s reward, motivation, and decision-making systems, all of which play a role in behaviours seen in offenders

Question 19

Why does research suggest a link between dopamine and crime?

Answer 19

Offenders are often motivated by perceived rewards or lack of impulse control, traits associated with dopamine

Question 20

Who identified a link between high dopamine and low serotonin regarding impulsivity, aggression and addictive behaviours?

Answer 20

Achebe et al., 2024

Question 21

Who investigated the dopamine reward system in those with psychopathic traits, and how?

Answer 21

• Buckholtz et al. (2010)
• used positron emission tomography (PET) and functional magnetic resonance imaging (fMRI)
• PET utilised radiotracers to view dopamine release upon receiving reward
• fMRI measured brain activity when anticipating a reward

Question 22

What did the Buckholtz et al. (2010) study find regarding dopamine and offending?

Answer 22

• heightened dopamine release when receiving reward
• heightened brain activity when anticipating reward
• this hypersensitivity to dopamine may relate to reward-seeking behaviours in individuals with psychopathic traits, leading to possible offending

Question 23

What are the limitations of the Buckholtz et al. (2010) study?

Answer 23

• it investigates psychopathic traits, which show a correlational relationship with offending, not causation
• focus was placed on differences between the two measured groups rather than the neurobiological mechanisms that may cause offending behaviours in individuals

Question 24

Who investigated gene polymorphisms in relation to dopamine?

Answer 24

Collins (2011)

Question 25

What are gene polymorphisms?

Answer 25

Genes that have multiple variants

Question 26

What did Collins' (2011) literature review find regarding genetic influences for offending related to dopamine?

Answer 26

- the D2 receptor gene is associated with antisocial behaviour - one variant of the D2 gene creates fewer D2 receptors, meaning that less dopamine can bind at a time - because of this, individuals are **more likely to partake in risky, offending behaviour** due to **increased reward seeking and lower impulse control**

Question 27

What are the limitations of Collins' (2011) study?

Answer 27

- the studies reviewed identify certain genes as **risk factors** for offending, demonstrating correlation, not causation - links observed may be due to complex biological or environmental factors, possibly influencing results