Ch. 3 Origins of Criminal Behavior: Biological Factors

Question 1

Early-Onset vs. Late-Onset Antisocial Behavior

Answer 1

Keywords: EARLY ONSET >> BIOLOGICAL, LATE-ONSET >> SOCIAL

Youngsters who follow an EARLY ONSET of persistent antisocial behavior often exhibit BIOLOGICAL/neurological abnormalities or deficits, while LATE-ONSET offending appears to be more influenced by SOCIAL factors.

• Social environment is the most important determinant of criminal behavior.

Question 2

Biopsychologist

Answer 2

Psychologists who study the BIOLOGICAL aspects of BEHAVIOR.

Question 3

Behavior Genetics

Answer 3

The branch of biology that investigates the RELATIONSHIP between GENES and the ENVIRONMENT in determining individual DIFFERENCES in BEHAVIOR.

• It DISTINGUISHES GENETIC from ENVIRONMENTAL INFLUENCES and estimating their RELATIVE MAGNITUDES.

Says behavioral differences result from THREE genetic or environmental SOURCES:

1. Influences attributable to GENETIC effects
2. ENVIRONMENTAL influences SHARED by siblings (e.g., family environments)
3. Influences that arise from UNSHARED ENVIRONMENTAL experiences that make siblings differ from one another.

Question 4

Molecular Genetics

Answer 4

The field of biology that STUDIES the structure and function of GENES at the MOLECULAR level.

• Focused on specific genes as foundations for certain patterns of behavior.
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Question 5

Twins in Behavioral Genetics

Answer 5

IDENTICAL TWINS are often used in BEHAVIORAL GENETIC studies because IDENTICAL TWINS share the SAME GENES but can be exposed to DIFFERENT ENVIRONMENTAL influences

• Monozygotic (MZ) twins (or identical twins) develop from a single egg; they are ALWAYS the SAME sex and share the SAME GENES.
• Dizygotic (DZ) twins (also called fraternal twins) develop from two DIFFERENT fertilized eggs and are NO MORE GENETICALLY ALIKE than non-twin siblings.
  
  • They are, though, equally susceptible to prenatal environmental influences, such as nicotine or alcohol use by the mother during pregnancy.
• The MAGNITUDE of these genetic and environmental influences is usually obtained from statistical analyses that COMPARE IDENTICAL TWINS with FRATERNAL TWINS.

Question 6

Monozygotic (MZ) twins

Answer 6

Keywords: IDENTICAL TWINS = ONE EGG

MONOZYGOTIC twins are IDENTICAL TWINS – develop from a single egg; they are ALWAYS the SAME sex and share the SAME GENES.

• MONO means “one”, and the Female ZYGOTE (sex cell) is the EGG, so MONOZYGOTIC means “ONE EGG”.
• IDENTICAL TWINS are particularly useful in Behavioral genetic studies because they share the SAME GENES but can Have DIFFERENT ENVIRONMENTAL INFLUENCES
• Even IDENTICAL TWINS can develop with SEPARATE OUTER MEMBRANES (called Chorions) within the womb, causing some differences in biological influences.

Question 7

Dizygotic (DZ) twins

Answer 7

Keywords: “TWO EGGS” = DIFFERENT GENES.

DIZYGOTIC (DZ) twins (also called fraternal twins) develop from two DIFFERENT fertilized eggs and are NO MORE GENETICALLY ALIKE than non-twin siblings.

• DI means “two”, and the Female ZYGOTE (sex cell) is the EGG, so DIZYGOTIC means “TWO EGGS” = DIFFERENT GENES.
• They are, though, equally susceptible to PRENATAL ENVIRONMENT influences, such as nicotine or alcohol use by the mother during pregnancy.

Question 8

Why Study Identical Twins?

Answer 8

IDENTICAL (monozygotic MZ) TWINS share 100% of their GENES. So…

• If GENES are the CAUSE of BEHAVIOR, identical twins should display highly SIMILAR BEHAVIOR.
  
  • If they do not, then we may infer that the behavioral differences are due to ENVIRONMENTAL FACTORS.
• Because MZ twins share 100 percent of their genes, it can be inferred that a child’s genetic risk for antisocial behavior is high if his or her co-twin shows antisocial behavior and low if the MZ co-twin does not.

Question 9

Findings of Twin Studies

Answer 9

• GENES influence approximately 50% of the population variation in ANTISOCIAL behavior, suggesting that genetics plays a significant role in its development.
• DNA can be CHANGED by the ENVIRONMENT. Psychosocial influences can result in structural modifications to DNA that have profound influences on neuronal functioning and behavior.
• The NEGATIVE effects of all GENE influences can be NEUTRALIZED by warm, SUPPORTIVE PARENTING.
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Question 10

Shared Vs. Nonshared Environments (Twin Studies)

Answer 10

SHARED ENVIRONMENTS include prenatal and life experiences affecting BOTH TWINS in the same way.

• The MORE environment shared, the GREATER the SIMILARITY in behavior

NONSHARED ENVIRONMENTS, on the other hand, include living experiences that are DIFFERENT for EACH TWIN, such as being raised in a different home environment, participating in different activities, or even attending different schools.

• NONSHARED ENVIRONMENTS account for approximately 30% of the variation in ANTISOCIAL behavior.
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Question 11

Concordance

Answer 11

KEY CONCEPT: CONCORDANCE is the DEGREE to which RELATED PAIRS of subjects BOTH show a particular behavior or condition. (expressed as a %)

EX: Assume that we want to know the concordance of intelligence among 20 pairs of identical twins and 20 pairs of fraternals.

• 10 of the 20 pairs of the identical twins have approximately the same IQ score.
  
  • This translates to 10/20 = 50% CONCORDANCE
• But only 5 of the 20 pairs of the fraternal twins have approximately the same IQ score.
  
  • This translates to 5/20 = 25% CONCORDANCE
• INTERPRETATION:
  
  • The concordance for identicals would be TWICE that of fraternals, suggesting that HEREDITARY FACTORS play an IMPORTANT role in intelligence.
  • If, however, the two concordances were about the SAME, we would conclude that GENETICS is IRRELEVANT.

Question 12

Twins’ Early Development Study (TEDS)

Answer 12

A Closely watched study of 10,000 pairs of Twins born in the 1990s.

• TEDS data suggest heritability seems to play a modest role. Nevertheless, at least one personality feature that has been associated with antisocial behavior—the callous-unemotional trait—shows VERY HIGH heritability and little shared environmental influence.
• Also, those children with a GENETIC PREDISPOSITION to become troublesome and ANTISOCIAL were especially LIKELY to be that way IF they were MISTREATED.

Question 13

Do Genetic Influences Grow Stronger or Weaker as People Age?

Answer 13

GENETIC FACTORS play an INCREASINGLY PROMINENT role in the stability of AGGRESSION and ANTISOCIAL BEHAVIOR across the LIFE SPAN.

• ENVIRONMENTAL influences seem to WANE somewhat as a person moves into adulthood.
• PARENTAL INFLUENCES on AGGRESSIVE BEHAVIOR DECREASES with INCREASING AGE.

HOWEVER, This effect is particularly STRONG WITH MALES as FEMALES ARE MORE INFLUENCED by FAMILY and the ENVIRONMENT.

Question 14

Molecular Genetics (and the MAOA Gene)

Answer 14

Keywords: MAOA GENE CALMS – WITHOUT it (or with LOW-MAOA) INDIVIDUALS become AGGRESSIVE

• BAD ENVIRONMENT makes the effect WORSE
• GENES INDIRECTLY affect ANTISOCIAL BEHAVIOR by impairing BRAIN FUNCTION.

MOLECULAR GENETICS attempts to FIND SPECIFIC GENES that PREDISPOSE individuals to ANTISOCIAL BEHAVIOR?”

• Ex: The MAOA gene (about a third of humans have it) plays a role in PREVENTING ANTISOCIAL BEHAVIOR in humans.
• Interestingly, the LOW-ACTIVITY form of the MAOA gene (abbreviated MAOA-L) which has been commonly LINKED to AGGRESSION and violence.
• If the (MAOA) gene is DE-activated (neutralized) in mice, they become highly aggressive. REACTIVATING the MAOA gene returns to their NORMAL behavior patterns.
• In fact, in humans with the MAOA-L gene who were exposed to adversity in their childhoods were significantly more likely to report ANTISOCIAL BEHAVIOR in late adolescence and early adulthood.
• 7 GENES have been identified as being ASSOCIATED with ANTISOCIAL BEHAVIOR – they appear to contribute to IMPAIRMENTS in BRAIN STRUCTURE and function which, in turn, result in ANTISOCIAL BEHAVIOR.

Question 15

Psychophysiological Factors

Answer 15

PSYCHOPHYSIOLOGY is the STUDY of the INTERACTIONS between BEHAVIOR and the AUTONOMIC NERVOUS SYSTEM, which regulates involuntary functions, such as heartbeat, blood pressure, breathing, and is closely connected to the genetic makeup of the individual.

AUTONOMIC AROUSAL THEORY of CRIME says that CHRONIC OFFENDERS compared with those with no offending history will exhibit LOW LEVELS of AUTONOMIC AROUSAL across a wide variety of situations.

• LOW LEVELS of AROUSAL PREDISPOSE a person to CRIME because:

1. LOW AROUSAL produces FEARLESSNESS and also because
2. it ENCOURAGES ANTISOCIAL STIMULATION (excitement seeking)

• Persistent offenders experience little anxiety and fear and are not troubled about getting caught and punished.
• They find certain aspects of crime exciting and challenging.

On the other hand, HIGH LEVELS of AUTONOMIC AROUSAL experience FEAR and ANXIETY, which encouraged childhood socialization because of FEAR of DISAPPROVAL and PUNISHMENT.

AMYGDALA – a brain structure particularly important to consider because of its role in regulating fear and other emotional responses.

• The AMYGDALA is RELATED to PSYCHOPATHY and to the CALLOUS-UNEMOTIONAL traits that are often associated with ANTISOCIAL BEHAVIOR

Question 16

AMYGDALA

Answer 16

AMYGDALA – a brain structure particularly important to consider because of its role in regulating fear and other emotional responses.

The AMYGDALA is RELATED to PSYCHOPATHY and to the CALLOUS-UNEMOTIONAL traits that are often associated with ANTISOCIAL BEHAVIOR

Question 17

CALLOUS-UNEMOTIONAL

Answer 17

CALLOUS-UNEMOTIONAL traits (Showing no emotional concern for others) that are often associated with ANTISOCIAL BEHAVIOR

Question 18

Temperament

Answer 18

A child’s TEMPERAMENT is a “NATURAL” MOOD DETERMINED largely BY GENETICS and biological influences.

• HOW we interact with our ENVIRONMENT influences how that environment will interact with us.
• A smiling, relaxed, socially-interactive child is apt to initiate and maintain a DIFFERENT SOCIAL RESPONSE than a fussy, tense, and withdrawn child.
• A consistently ill-tempered child may become so frustrating to her parents that they feel overwhelmed and helpless in dealing with her. The parents’ resulting irritability may feed into the behavior of the child in a reciprocal fashion, producing a serious disruption in the parent-child relationship. Frustration may progress into physical or emotional abuse or neglect by the parents.
• Temperament INCREASES or DECREASES the PROBABILITY of ANTISOCIAL BEHAVIOR. It does NOT DETERMINE DIRECTLY whether an individual will or will not engage in antisocial behavior.
• Because TEMPERAMENT is believed to be BIOLOGICAL, existing from birth through the LIFESPAN, research on temperament, therefore, FOCUSES on the INFANT, because the connection between temperament and behavior seems uncomplicated at this stage and becomes more complex as the child matures and interacts with the psychosocial environment.

Question 19

Three Categories of Child Temperament

Answer 19

Three Categories of Child Temperament

1. Easy Child – Smily, adapts quickly, mild expression of emotion, regular biological functioning
2. Difficult Child – cranky, doesn’t adapt well, intense expression of emotion, irregular biological functioning
3. Slow to Warm-up Child – high activity, withdrawal from new stimuli, low adaptability, negative mood, and low intensity.

Question 20

What two behaviors are strong indicators of temperament?

Answer 20

Keywords: ACTIVITY and EMOTIONALITY are the 2 strongest indicators of TEMPERAMENT

• ACTIVITY refers to gross motor movement across a variety of settings and times, such as the movement of arms and legs, squirming, crawling, or walking.
• EMOTIONALITY refers to such features as irritability, sensitivity, ability to be soothed, and general intensity of emotional reactions.
• SELF-REGULATION the extent that a child controls his or her own behavior, independent of the control of others and the social environment – is another behavior that is often included in descriptions of temperament.
  
  • There is a strong connection between poor self-regulation and antisocial behavior across different social situations
  • MALES tend to have MORE DIFFICULTY with SELF-REGULATION than FEMALES

Question 21

Environmental Risk Factors

Answer 21

Exposure to a toxic or diseased PRENATAL ENVIRONMENT can be the FIRST ENVIRONMENTAL RISK FACTOR for a child. Alcohol, Drugs, Nicotine, as well as exposure to environmental pollutants, toxic materials, and neurotoxins by the Mother and by the newborn.

• NEUROTOXINS are trace elements, pesticides, chemicals, and biological elements that have toxic effects on the human nervous system.
• They DAMAGE NEURONS producing changes in behavior
• The FETUS and CHILDREN UNDER TWO are the most vulnerable.
• Linked to AGGRESSION and VIOLENCE
• Neurotoxins just ONE ELEMENT in a WIDE SPECTRUM of complex interwoven factors leading to ANTISOCIAL BEHAVIOR.
• POOR NUTRITION usually involves a DEFICIENCY in MICRONUTRIENTS (especially iron, calcium, zinc, and selenium), which have the ABILITY TO NEUTRALIZE the negative effects of many neurotoxins on the human nervous system.
• THREE NEUROTOXINS have received sufficient research to connect them to the development of antisocial behavior:

1. LEAD – Connected with significant behavioral disorders. Still found in old houses, soil, and imported products.

• Lead was banned from gas (1996) and paint (1977) in the US, but old houses still have lead paint, Jetfuel still has lead, old pipes can have lead – still a real problem.
• There is NO ACCEPTABLE level of LEAD in the blood.

1. CADMIUM – high levels of cadmium in the body have been LINKED to VIOLENT BEHAVIOR. – Mostly gotten from 2nd-hand smoke.
2. MANGANESE – This is a critical MICRONUTRIENT, but in quantities that are TOO LARGE, it becomes a TOXIN.

• For CHILDREN, OVEREXPOSURE to manganese may come PRENATALLY and from INFANT FEEDING.
• To help PREVENT this EXPOSURE, the MOTHER must have SUFFICIENT IRON, which prevents the absorption of MANGANESE.
• TWO NEUROTOXINS – linked to nervous system problems, but current evidence has yet to connect them significantly to cognitive and behavioral outcomes related to criminal behavior.
  1. MERCURY – Associated with a vast number of behavioral disturbances, HOWEVER…
• A DIRECT LINK of MERCURY exposure to criminal or ANTISOCIAL BEHAVIOR has NOT BEEN ESTABLISHED, primarily because of the inconsistency of research findings.
• EXPOSURE to mercury comes primarily from eating MERCURY-CONTAMINATED FISH.

1. POLYCHLORINATED BIPHENYLS (PCBs) –

Question 22

Fetal Alcohol Spectrum Disorder (FASD)

Answer 22

FASD is an umbrella term for a RANGE of CONDITIONS that result from alcohol exposure in utero. including

• Fetal alcohol syndrome (FAS)
• Partial fetal alcohol syndrome (pFAS)
• Alcohol-related neurodevelopmental disorder (ARND)
• Alcohol-related birth defects (ARBD)
  
  • All may produce cognitive and behavioral problems

Question 23

Effects of a Smoking During Pregnancy

Answer 23

The LINK between MATERNAL SMOKING during pregnancy and antisocial behavior in her children is quite STRONG for BOYS, but WEAK for GIRLS

• Despite the consistency across studies, it remains difficult to firmly conclude that maternal smoking promotes or causes antisocial behavior in children because the mothers who smoke during pregnancy are different in many aspects from those who do not, meaning there are many other confounding negative factors with women who smoke that make it difficult to isolate the effects of smoking alone.

Question 24

Facts About Traumatic Brain Injury (TBI)

Answer 24

Approximately 60 percent of the incarcerated population in the United States is believed to have some EVIDENCE of TBI in their background.

• The Link between TBI and ANTISOCIAL BEHAVIOR is especially strong if the brain dysfunction is located in the frontal lobe, which comprises about one-third of the front part of the human brain and is responsible for organized thought, planning, and self-regulation.

Question 25

Brain Plasticity

Answer 25

BRAIN PLASTICITY – refers to the RESPONSIVENESS of the DEVELOPING BRAIN to EXPERIENCE.

• The first 3 - 4 years of life are significant in the PREVENTION of ANTISOCIAL behavior.
• HOWEVER, the brain retains its capacity to grow throughout life, suggesting that early deprivation and harm can be treated and modified during later years, even in adults.

Question 26

Hormones and Neurotransmitters

Answer 26

NEUROTRANSMITTERS are chemicals manufactured in the brain involved in biochemical activity and transmission of messages in the nervous system.

SEROTONIN – The neurotransmitter serotonin may play the MOST SIGNIFICANT role in aggression and violence (

• A deficiency in SEROTONIN in the forebrain is largely responsible for aggressive, antisocial, and violent behavior according to the Serotonin Deficiency Hypothesis of human aggression, but the role of Seratonin does NOT seem to be that clear cut in reality.

DOPAMINE – The jury is still out as to whether the neurotransmitter dopamine plays a significant role in antisocial behavior.

Question 27

Executive Function

Answer 27

EXECUTIVE FUNCTION refers to the higher levels of cognitive processes that ORGANIZE and PLAN behavior, including logic and abstract reasoning. Executive function also PRIORITIZES the STEPS necessary for SOLVING PROBLEMS and is closely involved in self-control and SELF-REGULATION.