Transcript Chapter_3_-_Biology

Biological Theories
• Predispose to crime (not simply “cause”)
– “Crime” is a social definition
– Malum in se / mala prohibita
– Not all maladaptive behaviors are illegal
• Behavior is affected by ...
– Inherited characteristics
– Inherited characteristics, affected by environment
– Environment effects on health (injury, pollution, diet…)
• General agreement that biology and environment interact to affect
behavior
• Instructor feels that sociologists have tended to ignore biological (and
psychological) factors
– As we learn more about the human organism, more and more
winds up being explained by chemistry
Body Type (“somatotypes”)
• Sheldon linked physique and temperament
– Endomorph: Soft physique, relaxed and comfortseeking temperament
– Mesomorph: Muscled physique, active and assertive
temperament
– Ectomorph: Lean, frail physique, introverted
temperament
• Gluecks found correlation between mesomorph
somatotype and aggressive/antisocial/uninhibited
behavior
Family studies - Goring
• Examined relationship between heredity,
environment and length/frequency of imprisonment
– Heredity  imprisonment?
– Environment  imprisonment?
• Findings
– Environmental factors not correlated with imprisonment
• Poverty, broken homes, nationality, birth order
– Biological factors are correlated with imprisonment
• Physical size (smaller, worse off)
• Mental inferiority
• Criminal family members
Criticisms of Goring and family
studies
• Failure to adequately measure
environmental variables
• Current data does not suggest that crime
“runs rampant” in families
• Difficult to control for environmental
effects within families, as all are usually
exposed to similar circumstances
Twin studies
• Difficult to control environmental variables
– So, control heredity
• Fraternal twins: different eggs, different DNA
– Can inherit different biological factors
• Identical twins: one egg, same DNA
– Biological factors the same
• Look for similarities and differences in behavior
– Similarities between identical twins can be hereditary
or environmental; differences cannot be hereditary
– If behavior of sets of identical twins is more alike than
behavior of sets of fraternal twins, heredity may be
important
Studies of identical twins - Christiansen
• 6,000 pairs of male twins
– Male identical twins: 67 pairs where at least one was
registered as a criminal.
• In 36% of these pairs (n = 24) both were criminals
– Male fraternal twins: 114 pairs where at least one was
registered as a criminal
• In 12% of these pairs (n=14) both were criminals
– Higher concordance for serious crimes
• Issue: Could higher concordance of behavior for identical
twins be due to a more similar environment?
Twins reared apart
• Similar environments might make identical twins
act alike, so study identical twins reared apart
• Grove (32 pairs separated shortly after birth);
Christiansen (8 pairs).
– Both found evidence that antisocial behavior can be
inherited
• Walters - 1992 meta-analysis of 14 twin studies
– Considered sample size, quality of research design
– Support for hereditary basis to criminality
• May be difficult to control for
environmental effects
Adoption Studies
• Attempt to control for environmental effects
• Hutchings and Mednick
Boys not
delinquent
69%
Bio. father
Not criminal
Bio. father
31%
criminal
Boys
delinquent
51%
49%
• Biological fathers appear to influence boys’ criminality
• Further analysis by Mednick
– Number of court convictions of biological parents (not adoptive
parents) influences youth criminality, but only for property crimes
– Other influencers:
• Socioeconomic status of biological and adoptive parents
• Personality disorders of biological parents
• Number of placements before adoption
• Criminality of biological and adoptive fathers interacts
• Issues with adoption studies
– Low sample sizes
– Recent studies found link between heredity and behavior only for
minor and property crime (far more frequent than violent crime)
– Adoptive parents often more law-abiding than general population
Brain chemistry
• Neurotransmitters
– Chemicals that transmit electrical impulses in the brain
– Levels affected by medication, diet, drug use, stress
– Imbalance may promote aggressive or compulsive behavior
• Violence, drug use
• Hormones
– Testosterone: Documented role in animal aggression, effects found
in human research
• Issues
– Causal order: Aggression may be the cause (not the effect) of high
levels of hormones
– Booth and Osgood study
• Association between testosterone and adult deviancy
• BUT – effect of high levels mediated by social integration
High levels  lack of social integration  aggression
Central nervous system (CNS)
• Brain and spinal cord
• Cerebral cortex - outer portion of the brain
Four lobes (frontal,
temporal, parietal,
occipital)
Frontal and temporal lobes
control goal-directed
behavior, impulses and
emotions
CNS and criminal behavior
• Some evidence that abnormalities in the lobes may be
associated with violent and sexual offending
– Frontal dysfunction may be associated with violent
offending
– Temporal dysfunction may be associated with sexual
offending
– Violent sexual offenders may have both dysfunctions
• Issues
– Research methodology - no sampling (with a hammer,
everything’s a nail)
– Precise path to offending is unknown
Autonomic nervous system (ANS)
• Controls involuntary
functions: Blood pressure,
heart activity, intestinal
activity, hormone levels
• “Fight/flight” situations:
ANS prepares body to
respond
– Blood from stomach to
muscles
– Increases respiration
– Stimulates sweat
(increases electrical
conductivity of skin)
ANS - continued
• Anxiety (e.g., conditioned fear of being punished for
telling a lie) is basis for lie detection
• Anxiety may be the primary socializing agent for children
– They behave properly to avoid anxiety of punishment
• Hypothesis that defective response can interfere with
socialization
– Antisocial persons might be more difficult to
“condition”, so they are less likely to fear punishment
Non-hereditary (environmental) biological
factors: Drugs and alcohol
• Alcohol in lower doses increases aggressive behavior, especially in
males
• Marijuana may reduce but does not increase aggression
• Opiates may reduce aggression
– Chronic use may increase aggression
– Withdrawal from opiates may also increase aggression
• Methamphetamine, PCP and LSD may increase aggression
– May be especially true for those predisposed to violence
– Police anecdotes about extreme violence and strength displayed by
persons high on Meth and PCP
• No direct evidence of effect of cocaine on violence
– Association between violence and areas where rock cocaine is used
(inner cities)
– Note - “rock” cocaine is much more concentrated
Other environmental biological factors
• Lead in diet may affect brain functions
– May cause hyperactivity and antisocial behavior in
children
• Head injury with brain damage may cause violent behavior
– Decrease cognitive and social skills
– Headaches and irritability
– Damage frontal and temporal lobes, increasing anxiety,
anger and hostility
• Delivery complications correlated with violent offending
– Particularly when parents had psychiatric problems