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Criminology 2330 Biology and Criminal Behaviour

Criminology 2330 Biology and Criminal Behaviour. A Basic Issue. Is criminal behavior caused or is it the product of free will ? If caused , are criminals biologically different than non-criminals, or is it their social experiences that matter most?. Lombroso (1835-1909)

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Criminology 2330 Biology and Criminal Behaviour

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  1. Criminology 2330Biology andCriminal Behaviour

  2. A Basic Issue • Is criminal behavior caused or is it the product of free will? • If caused, are criminals biologically different than non-criminals, or is it their social experiences that matter most?

  3. Lombroso (1835-1909) • Father of Criminology • Atavism • Hypothesized bodily features predict criminal behaviour • Research in Italian prisons

  4. Charles Buckman Goring, at about the turn of the twentieth century, concluded in a well-controlled statistical study of Lombroso's thesis of atavism that “the whole fabric of Lombrosian doctrine, judged by the standards of science, is fundamentally unsound.” • LOMBROSO’S Legacy is the application of scientific approach to causes of crime

  5. Genetics and Criminal Behaviour • What are genes? Units of hereditary DNA • What is heritability? • Differences due to genes compared to environmental influences. • eye colour, height, diseases, mental disorders, IQ

  6. Common Misconceptions • A single gene exists for criminal behaviour. • Genetic influences preclude possibility of treatment. • Genetics cannot influence something that is socially constructed. • Fluctuating crime rates preclude a genetic influence.

  7. Crime Gene disorders are polygenic in nature • Influenced by many genes & cannot be traced to single gene Exception: Chromosomal Abnormalities XYY - “Supermale Syndrome” (tall, intellectually slow, and violent) ~ Over-represented in male inmates

  8. MAOA + risk for impulsivity & violence • team of researchers uncovered neurobiological factors that contribute significantly to violence in humans (2009) • X- chromosome linked monoamine-oxidase • shown to be associated with impulsive aggression in humans and animals • low activity MAOA enzyme group displayed higher aggression when paired with poor childhood environment when provocation is high

  9. Twin Studies • Concordance Rate • degree which related pairs both show a particular behaviour or condition. • If genetic component: then • MZ (who are genetically identical) will have higher concordance rates than DZ

  10. Twin Studies • This is regularly seen that identical twins have higher concordance rates for antisocial behaviors than fraternal twins, even when reared apart

  11. Adoption Studies Methodology • Study children separated from biological parents and raised by adoptive parents • Greater criminality among children with criminal biological parents (vs. children with non-criminal biological parents) suggests a genetic influence

  12. Adoption Studies • Adoption data allow us to examine the effects of environment on human development. • Typical adoption studies measure the traits behaviors of the offspring and of the adopted and biological parents. • These studies indicate that adopted children behave more like their biological parents than their adoptive parents. • Evidence also shows important interaction effects between having criminal biological parents and being adopted into a criminal household. Again, demonstrates the effects of environment on genetic expression.

  13. Adoption Studies Danish Adoption Study (Mednick et al., 1984, 1987) 14,427 children adopted 1924-1947 Reviewed conviction records of biological parents, adoptive parents, and adoptee • Large scale study. • Concordance rate for criminality was higher for biological parents than adoptive parents. If either biological parent had been convicted for a crime, the risk of criminality increased significantly for the adoptive child • No relationship in regards to the type of crimes committed between biological children and biological parents

  14. Summary: Concordance Rates • Clear & consistent evidence showing a genetic link to various human traits and behaviors. • All sources of data (family studies, twin studies, and adoption studies) converge on this conclusion indicating that genetics may contribute moderately to becoming criminal, but environment is also important. • The evidence comes from various countries & from independent researchers. • Biological predisposition that environmental factors may either inhibit or facilitate.

  15. Neuroanatomy • Different brain regions may predispose certain individuals to commit antisocial acts • Differences might be from Traumatic Brain Injury (TBI) or may reflect variations controlled by genes.

  16. Case study: Chris Benoit Professional wrestler well-known for appearances in WWE In June, 2007 he is believed to have hung himself after killing his wife and 7-year-old son. Post-mortem examination of Benoit’s brain revealed extensive damage a neurologist concluded the damage may have produced a form of dementia that brought about bizarre changes in Benoit’s behaviour McKeown & Karp, 2008 http://img.photobucket.com/albums/v452/bbsrock/flickr.jpg

  17. Benoit may have been suffering from repeated, untreated concussions throughout his wrestling career, ultimately leading to an unstable mental state. He "was one of the only guys who would take a chair shot to the back of the head...which is stupid.” Tests were conducted on Benoit's brain by Julian Bailes, the head of neurosurgery at West Virginia University, and results showed that "Benoit's brain was so severely damaged it resembled the brain of an 85-year-old Alzheimer's patient.” Tests conducted on Benoit's brain tissue have revealed he did in fact suffer from severe chronic traumatic encephalopathy (CTE), and had brain damage in all four lobes of the brain and brain stem. These tests revealed similar results to the study of the brains of four retired NFL players who have suffered multiple concussions, sank into depression and harmed themselves or others. Repeated concussions can lead to dementia, which can contribute to severe behavioral problems.

  18. Major Parts of the Brain of Concern to Criminologists

  19. Frontal Lobe • Higher order functions: reasoning, planning, judgment, patience, abstract thought, moral reasoning, aggression regulation • Temporal Lobe • Amygdala: emotional and fear situations • Hippocampus: memory, learning, emotion regulation • Parietal Lobe • Sensory information related to movement and space • Cingulated gyrus • Surrounds the Corpus Callosum (joins right and left hemispheres) • Limbic system includes amygdala, hippocampus and cingulated gyrus • Emotional regulation, autonomic expression of emotions • (basic drives, fight or flight response) • MANY BRAIN STRUCTURES CAN IMPACT AGGRESSION!

  20. Key Points Frontal Lobe – Inhibition and Self control Temporal Lobe – Feeding, Fleeing, Fighting, Fornicating

  21. Frontal Lobotomy • In 1935, researchers in U.S reported that damaging frontal lobes and a nearby region of the brain called the prefrontal cortex could pacify a previously aggressive chimpanzee • consists of cutting the connections to and from the prefrontal cortex -- anterior part of the frontal lobes of brain • Carried out mostly in 1940s to mid 1950s to curb aggression • "ice-pick lobotomy" -- tap an ice pick through the thin bone on the roof of eye sockets; with the ice pick in the brain, sweep it back and forth to cut the frontal lobe's connections to the rest of the brain • Done to thousands of psychiatric patients

  22. Phineas Gage Sept. 13th, 1848: • Gage, a railway worker, had a tamping iron iron rod (37 by 1.25 ) explode through his left cheek and up through his frontal lobe. Effects of brain damage • Gage survived but demonstrated drastic changes in personality and cognitive functioning. • -hostility, verbal aggression

  23. Frontal Lobe Damage Frontal lobe deficits facilitating violence: • Deficits in inhibitory control • No stop & Think • Deficits in planning (Impulsivity) • Decreased capacity to self-correct, learn, and think flexibly • Rigidity (learning deficits) • Continuing a response after it is no longer appropriate • Interpersonal inappropriateness • Unable to read social cues

  24. Incidence of Acquired Brain Injury • 50,000 Canadians sustain a traumatic brain injury every year • majority are young men b/w ages of 15-30 • males experience brain injury twice as often as females • More than half people w/ brain injuries are under age of 20 • highest incidence in the 15 to 19 age range Brain Injury Association Network

  25. Traumatic Brain Injury • juvenile & adult violent offenders characterized by hx of significant head injury likely be caused by accidents or early child abuse (95% of infant head injuries due to child abuse) • 50% of offenders suffered a head injury as compared with 5-15% of non-offenders (Sarapata et al., 1998). • Head injured show raised levels of antisocial & violent • Does impulsivity cause head injuries or does head injuries cause impulsivity???

  26. Temporal-Limbic Damage -unprovoked or exaggerated anger, memory, and intellectual impairment -Auditory or visual hallucinations -Delusions -Receptive Language Impairment The Amygdala -key roles in emotions, fear responses and pleasure. -stimulation in monkeys increases aggression. -stimulation in humans results in heightened emotionality with fear and rage. Left Hemisphere Dysfunction

  27. Charles Joseph Whitman Died Age 25 As a student at the University of Texas at Austin, killed 14 people and wounded 32 others during a shooting rampage on and around the university's campus. The tower massacre happened shortly after Whitman murdered his wife and mother at their homes. He was shot and killed by Austin Police Officers. Charles Whitman grew up in an upper-middle class family headed by a father who owned a successful plumbing contract business in Florida. Whitman excelled at academics and was well liked by his peers and neighbors. There were underlying dysfunctional issues within the family that escalated in 1966, when the mother left the father and moved to Texas. The elder Whitman was an authoritarian who provided for his family, but demanded near perfection from all of them. He was also known to become physically and emotionally abusive.

  28. His frustrations were complicated by a dysfunctional family, abuse of amphetamines, and health issues including headaches that he reported in one of his final notes as "tremendous."A cancerous brain tumor, was discovered during autopsy that experts claimed may have conceivably played a role in causing his actions. It was revealed during the autopsy that Whitman had a tumor in the hypothalamus region of his brain. Some have theorized that this may have been pressed against the nearby amygdala, which can have an effect on flight responses. This has led some neurologists to speculate that his medical condition was in some way responsible for the attacks, as well as his personal and social frames of reference. http://www.youtube.com/watch?v=hA4M04prVK8

  29. Autonomic Arousal Theory of Crime Low levels of arousal, predisposes a person to crime Creates fearlessness Encourages thrill seeking behaviors (antisocial stimulation) As a result, they have low levels of anxiety and fear Conversely, high levels of autonomic arousal encourage positive behaviors due to the fear of disappointment and punishment

  30. Neurochemistry & Antisocial Behaviour • Neurotransmitters (chemical messengers) • convey “information” in the form of an electrically charged signal from neuron to neuron & from brain structure to brain structure

  31. Norepinephrine (ne) • “Fight & flight” response; related to arousal, mood, & behavioural activation • NE & Violence • indirect relationship to aggression • e.g., Amphetamine use & aggression (releases norepinephrine, dopamine and serotonin but then creates a state of depletion) • NE activity levels are impacted by medications used in treatment of violence (e.g. clozapine or other antipsychotics)

  32. Serotonin • involved in many functions including mood, arousal & impulse regulation • Important in its association with aggression • Lots of serotonin in the frontal cortex = executive functioning, self-regulation Low serotonin = disinhibition of aggression upon provocation low serotonin levels & aggressiveness (examples) • negative correlation b/w serotonin level & measures of aggression in psychiatric patients • low serotonin reported in children w/ disruptive behaviour & low levels have been linked to crime • Low serotonin levels in people who completed suicide

  33. Serotonin & alcoholism • Low levels may contribute to inability to inhibit behaviour and impulsive urges when drinking. • Alcohol lowers serotonin more in individuals who already have deficiencies in serotonin. • When drinking, these individuals more likely to feel hostile & negative.

  34. Dopamine • Dopamine = pleasure center • Rewards increase levels of Dopamine • Porn addictions??

  35. Biochemistry – Hormones: Testosterone • voluntary castration allowed in Federal Republic of Germany (since 1970) • follow-up of 99 castrated sex offenders & 35 non-castrated sex offenders for, on average, 11 years after release • recidivism rate over an average of 11 years post-release was 3% in castrated offenders compared to 46% in non-castrated offenders

  36. Testosterone: Women • Compared levels of testosterone among 3 groups of female inmates 1) violent crime (homicide, assault, or robbery) 2) non-violent (theft, forgery, drug trafficking) 3) defensive violence (homicide or assault against someone who had abused the inmate) • Inmates involved in violent crimes had higher testosterone values than those in other two groups

  37. “Other” Biological Factors • PMS - in one sample of 156 convicted women, 46% of crimes had occurred either 4 days prior to or after menstruation; a figure higher than expected by chance (29%). • Hypoglycemia (“twinkee defence”)

  38. A small note about sexual offenders • Research by James Cantor • Left handedness – pedophiles • Significant difference between IQ for pedophiles and those who prefer adult partners (IQ below 90 vs IQ average 100) – Cantor (2004) • Pedophiles more head injuries BEFORE age 13 than those who prefer adult partners • Pedophiles are significantly SHORTER (by 2 cm)

  39. More about pedophiles… • You can differentiate pedophiles with an MRI in GROUPS • With an fMRI you can see differences on how pedophiles respond to children vs how normals respond to adults • http://individual.utoronto.ca/james_cantor

  40. Other biological aspects • Food and nutrition! - early malnutrition at age 3 can impact brain development and lead to antisocial behaviors later in life • The resulting brain impairments resulting from malnutrition impact executive functioning • Good nutrition can reduce recidivism • Neurotoxins (e.g. lead) • Birth complications

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