LECTURE #2 - Biological Theories of Crime

Levels of analysis chart

levels of analysis: mechanism

• how does it work?

• what makes it happen?

  • involves …

    • physiology

    • brain networks

    • stress

    • peers

levels of analysis: development

• when did it develop?

• what leads to its expression?

  • involves …

    • gene-environment interactions

    • biological sex

    • relationship experiences over time

levels of analysis: evolution

• why does it exist?

• how did it impact survival or reproduction?

  • involves …

    • adaption to specific environments

    • help acquire resources

    • help acquire status

    • help acquire mates

bio explanations of crime

• genetics

• hormones

• neurotransmitters

• psychophysiology

• neurology

• neuropsychology

• evolutionary mechanics

SRY gene

• significantly linked to criminal behaviour more than chance

• determines sex

twins and criminal behaviour

• 81% chance of MZ twin criminal offending if their twin has

• 61% chance of DV twin criminal offending if their twin has

limitations of behaviourial genetics

• parents treat mz twins more similar

• only tells you that genes are involved not how or which ones

the warrior genes

• monoamine oxidase A (maoa gene)

  • high activity version

  • low activity version

• produces a protein enzyme that breaks down neurotransmitters in the brain

polygenic score for crime

• every gene has some probability associated with crime

• degree to which an individual’s genotype contains genes associated with crime

testosterone

• linked to aggression

• only in males

• mainly when cortisol is activated

serotonin

• linked to antisocial behaviour

psychophysiology

• relationship between psychological and physiological processes

• psychological - emotions, thoughts, beliefs, motivations

• physiological - heart rate (bpm 90), skin conductance, eeg, butt movement

heart rate

• could examine resting or reactivity

• normal resting range: 60-100 bpm

• linked to antisocial behaviour

antisocial behaviour

• fearlesness + stimulation seeking

  • unconcerned and unaroused

neurology

• two brain areas are reliably associated with criminal behaviour:

1. prefrontal cortex

2. limbic system structures

what specific functional capacities affected most?

• emotion regulation

• social cognition

• self-reflection

• impulse control

the case of mr. oft

• 40-yr-old, well-educated man with a clean history

• started watching child porn, sought out prostitution, ended up sexually assaulting his own step daughter

• step daughter reported the assault to her mother, who turned him in

• given the choice of being sent to a sex addiction center, or just going to jail

• he was sent to the sex addiction center with a pedophilic diagnosis

• sexual acts continued even during the rehab

• ended up showing odd symptoms, like loss of balance and doctors checked for injury

• huge tumor in his prefrontal cortex - controls his inhibitions

• post removal, his sexual deviancy stopped and he felt extremely guilty and remorseful for his actions

neuropsychology

• psychological functions that underlie specific neurological structures and networks

executive functions

• self-regulation

• self-directed thoughts and actions needed to:

  • choose goals

  • create actions towards those goals

  • enact those actions

  • sustain them over time

core of evolutionary theory

• traits and behaviour getting gradually ”chosen” for the next generation by environmental demands

• whole organisms are composed of different traits and behaviours

• each have different functions

what does function mean in evolutionary terms? they have enabled or increased . . . ?

• survival

• reproduction

types of selection

• natural

• sexual

natural selection

• competition for resources

• especially influences who survive

sexual selection

• competition for mates

• especially influences who reproduces

insights from evolution for crime

• motivators of criminal behaviour

• costs and benefits of crime depend on environment

functions of criminal behaviour (3)

• access to mates

  • competing with rivals

  • accessing partners

• access to resources

  • acquiring desirable goods

  • making a living

• obtain status